Kappa Leporis

Kappa Leporis, Latinized from κ Leporis, is a binary star system in the southern constellation of Lepus. The pair have apparent visual magnitudes of 4.43 and 7.00, with the former being bright enough to be seen with the naked eye. As of 2000, they had an angular separation of 2.179 arc seconds along a position angle of 357.3°. Based upon an annual parallax shift of 4.48 mas as measured from Earth, the system is located roughly 730 light years from the Sun. The system is travelling away from the Sun with a radial velocity of +20.8 km/s.
The brighter, blue-white hued member of the system, component A, is a B-type main-sequence star with a stellar classification of B9 V. It has nearly five times the mass of the Sun and around 2.6 times the Sun's radius. The star is radiating 1,346 times the Sun's luminosity from its photosphere at an effective temperature of 11,588 K. It displays an infrared excess at a wavelength of 12μm, making it a candidate host for a circumstellar debris disk.


NGC 6366

NGC 6366 is a globular cluster located in the constellation Ophiuchus. It is designated as XI in the galaxy morphological classification scheme and was discovered by the German astronomer Friedrich August Theodor Winnecke on 12 April 1860. It is at a distance of 11,700 light years away from earth.<ref name="NASA/IPAC"></ref>
NGC 6366 is similar in composition to M 71 or NGC 6342. It is metal-rich for a globular cluster, and all of its stars appears to have formed in the same epoch.


Mu Lyrae

μ Lyrae, Latinized as Mu Lyrae, is a solitary star in the northern constellation Lyra. It has the traditional name Alathfar , from the Arabic الأظفار "al-ʼaẓfār" "the talons (of the swooping eagle)", a name it shares with Eta Lyrae (though the latter is spelled "Aladfar" by the IAU). This white-hued object is visible to the naked eye as faint point of light with an apparent visual magnitude of 5.11. It is located approximately 412 light years distant from the Sun based on parallax, but is drifting closer with a radial velocity of −24 km/s.
This object has evolved off the main sequence, becoming a subgiant with a stellar classification of A0 IV. It has a fairly high rate of spin, showing a projected rotational velocity of 165 km/s. This is giving the star an equatorial bulge that is an estimated 17% larger than the polar radius. The star has three times the mass of the Sun and about 4.5 times the Sun's radius. It is radiating 200 times the Sun's luminosity from its photosphere at an effective temperature of 9,016 K.


List of stars in Auriga

This is the list of notable stars in the constellation Auriga, sorted by decreasing brightness.


N Carinae

N Carinae is a single star in the constellation Carina, just to the northeast of the prominent star Canopus. This object has a white hue and is faintly visible to the naked eye with an apparent visual magnitude of 4.35. Based on parallax, it is located at a distance of approximately 1,360 light years from the Sun. It has an absolute magnitude of −3.75, and is drifting further away with a radial velocity of +22.5 km/s.
This object has a stellar classification of A0II, matching a massive bright giant. In the past it had received a class of B9III, which is sometimes still used. The star is 37 million years old with 7.9 times the mass of the Sun. It is spinning with a projected rotational velocity of 47 km/s. N Carinae is radiating 3,411 times the luminosity of the Sun from its photosphere at an effective temperature of 8,004 K.


PU Puppis

PU Puppis (PU Pup) is a class B8III (blue giant) star in the constellation Puppis. Its apparent magnitude is 4.69 and it is approximately 620 light years away based on parallax.
It is a β Lyrae variable, ranging from 4.75 to 4.69 magnitude with a period of 2.58 days. The secondary is estimated at about 5.6 magnitude, although recent observations have failed to confirm it.


8 Vulpeculae

8 Vulpeculae is star located about 457 light years away in the northern constellation of Vulpecula. It lies just from Alpha Vulpeculae and the two form an optical double. 8 Vulpeculae is visible to the naked eye as a faint, yellow-orange hued star with an apparent visual magnitude of 5.82. It is moving closer to the Earth with a heliocentric radial velocity of −29 km/s.
This is an aging giant star with a stellar classification of K0 III, which indicates it has exhausted the hydrogen supply at its code and evolved away from the main sequence. It is 324 million years old with three times the mass of the Sun and has expanded to 14 times the Sun's radius. The star is radiating 100 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,915 K.


Delta Hydrae

Delta Hydrae, Latinized from δ Hydrae, is a double star in the equatorial constellation of Hydra. It is visible to the naked eye with an apparent visual magnitude of 4.146. Based upon an annual parallax shift of 20.34 mas, it is located about 160 light years from the Sun.
This is a double star with an angular separation of along a position angle of , as of 2003. The brighter component is an A-type main sequence star with a stellar classification of A1 Vnn. It is spinning rapidly with a projected rotational velocity of 285 km/s. This is giving the star an oblate shape with an equatorial bulge that is 20% larger than the polar radius. It has an estimated 2.88 times the mass of the Sun and 2.7 times the Sun's radius. The star is about 244 million years old and it radiates 42.7 times the solar luminosity from its outer atmosphere at an effective temperature of 11,055 K.
The companion has a visual magnitude of 11.15. X-ray emissions have been detected from this location in space, which may be coming from a companion star.
Name and etymology.
In the catalogue of stars in the "Calendarium of Al Achsasi Al Mouakket", this star was designated "Lisan al Shudja", which was translated into Latin as "Lingua Hydri", meaning "the snake's tongue". This star, along with ε Hya, ζ Hya, η Hya, ρ Hya and σ Hya (Minchir), were Ulugh Beg's "Min al Azʽal", "Belonging to the Uninhabited Spot".
According to the catalogue of stars in the "Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars", "Min al Azʽal" or "Minazal" were the title for five stars :δ Hya as "Minazal I", η Hya as "Minazal II", ε Hya as "Minazal III", ρ Hya as "Minazal IV" and ζ Hya as "Minazal V" (exclude σ Hya)
In Chinese, (), meaning "Willow (asterism)", refers to an asterism consisting of δ Hydrae, σ Hydrae, η Hydrae, ρ Hydrae, ε Hydrae, ζ Hydrae, ω Hydrae and θ Hydrae Consequently, δ Hydrae itself is known as (, .)
The people of Groote Eylandt called "Unwala", "The Crab", for the star cluster including this star, ε Hya, ζ Hya, η Hya, ρ Hya and σ Hya (Minchir).


MT Pegasi

MT Pegasi (HD 217813) is a single, yellow-hued star in the northern constellation of Pegasus. With an apparent visual magnitude of 6.616, it is a dim star that is at or below the nominal limit for visibility with the naked eye. Based upon an annual parallax shift of as measured from Earth's orbit, it is located 79.31 light years away. This star is a member of the Ursa Major Moving Group, a collection of stars that originated in the same open cluster and now share a common motion through space.
This is a G-type main-sequence star with a stellar classification of G1 V. Harlan and Taylor (1970) had assigned it a class of G5 V, but this gives a poor match to the color index. HD 217813 was found to be variable in 1995 and hence it was given the variable star designation MT Pegasi (MT Peg). It displays brightness variations with a period of several days, which is caused by star spots that are modulated by the star's rotation period. MT Peg is classified as a BY Draconis variable.
MT Peg is considered a young solar analog, which means it is a solar-type star representative of how a young, more active Sun may have appeared when it was less than 1.5 billion years old. The estimated age based upon the chromospheric activity level is 397 years, per Gray et al. (2015). Marsden et al. (2014) gave a larger age estimate of 1.2 billion years, but with a margin of error that overlaps the younger value. Age estimates of the Ursa Major group are around 300 million years old.
The star has 1.07 times the mass of the Sun and 1.01 times the Sun's radius. It is spinning with a projected rotational velocity of 3.2 km/s, giving it a rotation period of 5.8 days. The elemental composition of the stellar atmosphere is similar to the Sun. MT Peg is radiating 1.07 times the Sun's luminosity from its photosphere at an effective temperature of 5,885 K.


HD 82886

HD 82886 is an evolved giant star in the constellation Leo Minor. With an apparent magnitude 7.63, it is too faint to be seen with the unaided eye.
Planetary system.
A planet 1.3 times the mass of Jupiter and orbiting at an approximate distance of 1.65 astronomical units (AU) every 705 days was discovered in 2011.
HD 82886, and its planet HD 82886b, were chosen as part of the 2019 NameExoWorlds campaign organised by the International Astronomical Union, which assigned each country a star and planet to be named. HD 82886 was assigned to Albania. The winning proposal named the star Illyrian after the ancient people of the Balkans region (including Albania), and the planet Arber after the medieval term for the inhabitants of Albania.


Beta Scuti

Beta Scuti, Latinized from β Scuti, is a binary star system in the southern constellation Scutum. Based upon an annual parallax shift of 3.56 mas as seen from Earth, it is located approximately 920 light years from the Sun. The primary component has an apparent visual magnitude of +4.22 and is radiating about 1,270 times the luminosity of the Sun from its outer atmosphere at an effective temperature of 4,622 K. This yellow-hued star is a G-type bright giant with a stellar classification of G4 IIa.
This is a spectroscopic binary with an orbital period of 2.3 years and eccentricity around 0.35. The secondary is about 3.3 magnitudes dimmer than the primary and estimated as type B9 based on the flux of far-ultraviolet radiation.
The secondary was directly detected with a magnitude difference of 3.6 at a separation of about 17 milli-arcseconds using observations
from the Navy Precision Optical Interferometer. This detection was significant as observations with the Hubble Space Telescope which indicated a companion star was present were not definitive. With an orbit and a parallax the sum of the masses of the two stars can be determined via a dynamical parallax. This eventually can yield a precise mass for the evolved giant primary star.
Beta Scuti was a latter designation of 6 Aquilae.


RR Ursae Minoris

RR Ursae Minoris, abbreviated RR UMi, is a binary star system in the northern circumpolar constellation of Ursa Minor. It can be viewed with the naked eye, typically having an apparent visual magnitude of around 4.710. Based upon an annual parallax shift of as seen from Earth's orbit, it is located 330 light years away. The system is moving further from the Sun with a heliocentric radial velocity of +6 km/s.
This star was found to have a variable radial velocity by J. H. Moore in 1910. It is a single-lined spectroscopic binary system with an orbital period of and an eccentricity (ovalness) of 0.13. The "a" sin "i" value is , where "a" is the semimajor axis and "i" is the orbital inclination to the line of sight from the Earth. This gives a lower bound on the physical size of the orbit. The system is a source for X-ray and far-UV emission, with the latter most likely coming from the companion.
The visible component is an aging red giant star on the asymptotic giant branch with a stellar classification of M4.5 III. It was found to be a variable star by J. Ashbrook in 1946, and is catalogued as a semiregular variable of subtype SRb that ranges from magnitude 4.44 to 4.85 over a period of 43.3 days. However, variations in the period have been observed on a time scale of 30–60 days. The star has 1.15 times the mass of the Sun and has expanded to 60 times the Sun's radius. It is radiating 757 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 3,464 K.


NGC 5033

NGC 5033 is an inclined spiral galaxy located in the constellation Canes Venatici. Distance estimates vary from between 38 and 60 million light years from the Milky Way. The galaxy has a very bright nucleus and a relatively faint disk. Significant warping is visible in the southern half of the disk. The galaxy's relatively large angular size and relatively high surface brightness make it an object that can be viewed and imaged by amateur astronomers. The galaxy's location relatively near Earth and its active galactic nucleus make it a commonly studied object for professional astronomers.
Nucleus.
NGC 5033 contains a Seyfert nucleus, a type of active galactic nucleus. Like many other active galactic nuclei, this galaxy's nucleus is thought to contain a supermassive black hole. The bright emission seen in visible light (as well as other wavebands) is partially produced by the hot gas in the environment around this black hole.
Integral field spectroscopic observations of the center of NGC 5033 indicate that the Seyfert nucleus is not located at the kinematic center of the galaxy (the point around which the stars in the galaxies rotate). This has been interpreted as evidence that this galaxy has undergone a merger. The displacement of the Seyfert nucleus from the kinematic center may destabilize the rotation of gas in the center of the galaxy, which could cause gas to fall into the Seyfert nucleus. The gas would be compressed by the enormous gravitational forces in the center of the Seyfert nucleus and become hot, thus making the nucleus appear bright or "active".
Nearby galaxies.
NGC 5033 and the nearby spiral galaxy NGC 5005 comprise a physical galaxy pair. The two galaxies weakly influence each other gravitationally, but they are not yet close enough to each other to be distorted by the tidal forces of the gravitational interaction. The fainter irregular galaxy IC 4182 is also a member of this group.


48 Cassiopeiae

48 Cassiopeiae is a triple star system in the northern constellation of Cassiopeia. It is visible to the naked eye with a combined apparent visual magnitude of 4.49. With an annual parallax shift of as seen from Earth's orbit, it is located approximately 115 light years away. The system is moving closer with a heliocentric radial velocity of −12.4 km/s.
The primary component, designated 48 Cassiopeiae A, is a white A-type main-sequence star with a stellar classification of A2 V and an apparent magnitude of +4.65. It has a companion, component B, which is an F-type main-sequence star of class F2 V and an apparent magnitude of +6.74. This pair orbit around their common centre of mass once every 61.1 years. They have a semimajor axis of 0.614 arcseconds and an eccentricity of 0.355. A third companion, component C, is a magnitude 13.20 star located at an angular separation of 23.16 arcseconds as of 2014, or at least 816.5 AU away.
48 Cassiopeiae also has the Bayer designation A Cassiopeiae, the only star with a Latin letter designation in the constellation.


57 Pegasi

57 Pegasi is a variable binary star system in the northern constellation of Pegasus (constellation). It has the variable star designation GZ Pegasi, while "57 Pegasi" is the Flamsteed designation. The system is faintly visible to the naked eye as a point of light with an apparent visual magnitude that fluctuates around 5.105. It is located at a distance of approximately 780 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +14 km/s.
The variability of this star was discovered by J. Stebbins and C. M. Huffer in 1930. It was classified as a long-period variable of type Lb in 1974. However, based on a constant period and the shape of the light curve, it was later reclassified as a semiregular variable of type SRa in 1978. It varies in brightness from magnitude 4.95 down to 5.23 with a period of 92.66 days. The spectrum of 57 Peg displays blended features that indicate this is a binary system consisting of an aging red giant star on the asymptotic giant branch with a stellar classification of M4IIIa, and a fainter but hotter A-type main-sequence companion of class A3V. This spectroscopic binary system has poorly constrained orbital elements with an estimated orbital period of 100–500 years.
The red giant primary has been designated as an S-type star that shows enriched levels of s-process elements in its spectrum. However, it does not display significant lines of radioactive technetium-99 in its spectrum, indicating that the s-process elements must have been acquired from a mass transfer event from a formerly asymptotic giant branch companion that had passed through multiple dredge-up events. This would suggest it has a white dwarf as a tertiary companion, but this is incompatible with the data findings. Instead, it might have been misclassified as an S-type star.
There is a magnitude 10.06 visual companion at an angular separation of along a position angle of 198° from the primary, as of 2015. Designated component B, this star was first reported by F. G. W. Struve in 1827.


NGC 3669

NGC 3669 (other designations - UGC 6431, MCG 10-16-135, ZWG 291.67, IRAS11226+5759, PGC 35113) is a barred spiral galaxy in the constellation Ursa Major. It was discovered by William Herschel on March 18, 1790. The galaxy is seen edge-on and appears to be slightly warped. It has a small bulge.
It is a member of the NGC 3610 galaxy group. Members of the group that lie at a smaller projected distance from NGC 3669 include NGC 3674 and NGC 3683A 40′–50′ to the south and southeast and NGC 3613 and NGC 3619 40′–50′ to the west. Four satellite candidates have been detected near NGC 3669.


NGC 373

NGC 373 is an elliptical galaxy located in the constellation Pisces. It was discovered on December 12, 1876 by Dreyer. It was described by Dreyer as "very faint, very small."


NGC 2020

NGC 2020 is an HII Region surrounding a Wolf-Rayet star. It is located in the Large Magellanic Cloud.
The nebula was discovered on 30 December 1836 by John Herschel. Together with NGC 2014 it makes up what is called the Cosmic Reef.


NGC 5000

NGC 5000 is a barred spiral galaxy in the Coma Berenices. It was discovered by William Herschel in 1785. It is also known as LEDA 45658, MCG+05-31-144, UGC 8241, VV 460, III 366, h 1544, and GC 3433.
Herschel discovered it with the help of 18.7-inch f/13 speculum telescope. It is very faint, very small and irregularly round with weak concentration.


Phi Hydrae

The Bayer designation Phi Hydrae (φ Hya / φ Hydrae) is shared by three star systems, in the constellation Hydra:
The three stars form a triangle between the brighter μ Hydrae and ν Hydrae.


List of stars in Lynx

This is the list of notable stars in the constellation Lynx, sorted by decreasing brightness.


NGC 6000

NGC 6000 is a barred spiral galaxy located in the constellation Scorpius. It is designated as SB(s)bc in the galaxy morphological classification scheme and was discovered by John Herschel on 8 May 1834. The galaxy is approximately 103 million light-years away. It is the brightest of all the galaxies in the constellation Scorpius.<ref name="NASA/IPAC"></ref><br>
Two Supernovae have been observed in this galaxy namely, 2007ch and 2010as, each having a mag. of about 17.2 and 15.5 respectively.


T Cephei

T Cephei is a Mira variable star in the constellation Cepheus. Located approximately distant, it varies between magnitudes 5.2 and 11.3 over a period of around 388 days.
Stellar Properties.
T Cephei is a red giant of spectral type M6-9e with an effective temperature 2,400 K, a radius of , a mass of , and a luminosity of . If it were in the place of the Sun, its photosphere would at least engulf the orbit of Mars. This star is believed to be in a late stage of its life, blowing off its own atmosphere to form a white dwarf in a distant future.


HD 44780

HD 44780 is a binary star system in the northern constellation of Gemini, located about 3° north of Mu Geminorum. The pair have a combined apparent visual magnitude of 6.35, which is near the lower limit of visibility to the naked eye. Although it is above magnitude 6.5, it was not included in the "Bright Star Catalogue"; the designation "HD 44780" comes from the Henry Draper catalogue. Based upon parallax measurements, the system is located at a distance of approximately 960 light years from the Sun. It is drifting further away with a radial velocity of +17 km/s.
The variable velocity of this system was first noted during a study at Mount Wilson observatory in 1952. It is a double-lined spectroscopic binary system with an orbital period of and an eccentricity of 0.24. Both components are similar, aging giant stars, a relatively rare combination. Their combined spectrum matches a stellar classification of K2 III; with the secondary being a slightly earlier type than the primary. They have an age of about 400 million years, with masses 3.10 and 3.02 times that of the Sun.


S Sagittae

S Sagittae, also known by the Flamsteed designation of 10 Sagittae, a Classical Cepheid variable in the constellation Sagitta that varies from magnitude 5.24 to 6.04 in 8.382 days. Its variable star designation of "S" indicates that it was the second star discovered to be variable in the constellation. Irish amateur astronomer John Ellard Gore was the first to observe its variability in 1885, and Ralph Hamilton Curtiss discovered its changing radial velocity in 1903–04. Harlow Shapley observed in 1916 that the spectrum of it and other Cepheids varied with its brightness, recording it as spectral type F0 leading to maximum, F4 at maximum, and G3 just before minimum brightness.
S Sagittae is a yellow-white supergiant that varies between spectral types F6Ib and G5Ib. It is around six or seven times as massive and five thousand times as luminous as the Sun and is located around 2,000 light-years away from Earth. Its radius is 58.5 times that of the Sun. The radius, temperature, luminosity, and colour are all variable as the star pulsates during its eight-day period. The period is slowly increasing.
S Sagittae has been reported as a double or triple system with a hotter main sequence star companion in a 676-day orbit. The companion, and its own possible fainter companion, are only detectable from radial velocity changes in the spectral lines of the Cepheid primary and an ultraviolet excess. Analysis of the spectrum indicates a star of spectral type A7V to F0V, and 1.5 to 1.7 times as massive as the Sun. However, as the mass of the companion is greater than 2.8 solar masses, this strongly suggests this companion is itself a binary star.


Delta2 Telescopii

Delta2 Telescopii is a blue-white hued binary star system in the southern constellation of Telescopium. It is faintly visible to the naked eye, having an apparent visual magnitude of 5.05. The distance to this system, as determined with an annual parallax shift of 2.73 mas, is roughly 1,200 light years. At that distance, the visual magnitude of the star is diminished by an extinction of 0.36 due to interstellar dust. The pair have an orbital period of 21.7 days and an eccentricity of 0.22. For the merged stellar classification, Houk (1978) gives B3 IV/V, while Levato (1975) lists a more evolved class of B3 III. It appears to be a relatively young system, barely 40 million years old.


U Lacertae

U Lacertae is a spectroscopic binary star in the constellation Lacerta.
Despite being in the constellation of Lacerta, U Lacertae is considered to be a member of the Cepheus OB1 association. It has been listed as a member of the open cluster ASCC 123.
U Lacertae is a VV Cephei binary consisting of a red supergiant and a small hot companion. The companion has been identified from a high excitation component in the spectrum and from radial velocity variations, but the orbit is unknown.
U Lacertae is a variable star classified as a semiregular variable. The periodicity is uncertain but a main period of 150 days and a long secondary period of 550 – 690 days have been suggested. A study of Hipparcos satellite photometry found an amplitude of 0.77 magnitudes and found no periodicity. The General Catalogue of Variable Stars lists an amplitude of 2.7 magnitudes.
Water masers have been detected around U Lacertae, common in the extended atmospheres of very luminous cool stars.


Iota Cassiopeiae

Iota Cassiopeiae (ι Cas, ι Cassiopeiae) is a star system in the constellation Cassiopeia. The system has a combined apparent magnitude of 4.53, making it visible to the naked eye. Based on its parallax, it is located about 133 light-years (41 parsecs) from Earth.
Components.
Iota Cassiopeiae is known to be a quintuple star system. The brightest star system, ι Cassiopeiae A, contains a white-colored A-type main-sequence star with a mean apparent magnitude of +4.61. The primary component is a tighter binary star system itself. The two stars themselves were resolved by adaptive optics, revealing two stars. These are designated Aa and Ab (although confusingly they may also be labeled as A and Aa, respectively). The primary is classified as an Alpha2 Canum Venaticorum-type variable star and the brightness of the system varies from magnitude +4.45 to +4.53 with a period of 1.74 days, because of its magnetic field. The fainter companion is a G-type star with a mass of only . The orbital period of the system is about 50 years.
A second component, ι Cassiopeiae B, is a yellow-white F-type main sequence dwarf with an apparent magnitude of +6.87. The semimajor axis of its orbit is 2.88 arcseconds, and it has an orbital period of 620 years around ι Cassiopeiae A.
The third astrometric component, ι Cassiopeiae C, is another binary like ι Cassiopeiae A. It comprises two stars, a K-type star and a M-type star. It orbits at an angular distance of 7 arcseconds from the A-B primary.


4 Cassiopeiae

4 Cassiopeiae is a wide binary star system in the northern constellation of Cassiopeia, located approximately 790 light-years away from the Sun. It is visible to the naked eye as a faint, red-hued star with a baseline apparent visual magnitude of 4.96. At the distance of this system, its visual magnitude is diminished by an extinction of 0.56 due to interstellar dust. This system is moving closer to the Earth with a heliocentric radial velocity of −39 km/s.
The primary member of this system, component A, is an evolved red giant star, currently on the asymptotic giant branch, with a stellar classification of M2− IIIab. It is a suspected variable star of unknown type with a brightness that varies from visual magnitude 4.95 down to 5.00. As of 2011, the magnitude 9.88 secondary, component B, lay at an angular separation of along a position angle of 226° relative to the primary. In the sky, the open cluster Messier 52 is 40' to the south of it, near the constellation border with Cepheus.


R Centauri

R Centauri (R Cen) is a Mira variable star in the constellation Centaurus. It is approximately 1,300 light years from Earth.
R Centauri is a Mira variable and its brightness varies from magnitude +5.2 to +11.5 with a period of about 500 days. It used to have an unusual double-peaked light curve, but by 2001 this had reverted to an almost normal single-peaked curve. Prior to 1950 the period was about 550 days, but since then has decreased to about 500 days. A 2016 analysis of ASAS data derived a period of 498.84 days.
It is thought that the unusual behaviour of R Centauri is caused by a flash in the helium shell around its core, which occurs periodically in asymptotic giant branch (AGB) stars as the mass of the helium shell increases with helium from the outer hydrogen shell.
It is also an H2O maser source.


45 Herculis

45 Herculis is a solitary variable star in the northern constellation Hercules. It has the Bayer designation l Herculis and the variable star designation V776 Herculis. The Flamsteed designation for this star comes from the publication "Historia Coelestis Britannica" by John Flamsteed. It is the 45th star in Flamsteed list of stars in the constellation Hercules, and is visible to the naked eye with a baseline apparent visual magnitude of 5.22. Parallax measurements show this star to be about 400 light-years away from the Solar System. It is moving closer to the Earth with a heliocentric radial velocity of −16 km/s.
Cowley et at. (1969) assigned this object a classification of , while Abt and Morrell (1995) found a class of . Both indicate this is a late B- or early A-type chemically peculiar, or Ap star, with abundance anomalies in chromium or silicon. It is an Alpha2 Canum Venaticorum variable that ranges in visual magnitude from 5.21 down to 5.27. The star has 2.9 times the mass of the Sun and 4.9 times the Sun's radius. It is radiating 120 times the Sun's luminosity from its photosphere at an effective temperature of 9,333 K.


NGC 6052

NGC 6052 is a pair of galaxies in the constellation of Hercules. It was discovered on 11 June 1784 by William Herschel. It was described as "faint, pretty large, irregularly round" by John Louis Emil Dreyer, the compiler of the New General Catalogue.
The two components of NGC 6052 are designated NGC 6052A and NGC 6052B, respectively. The two, attracted by each other's gravity, have collided and are interacting with each other. NGC 6052 is currently in a late stage of merging, where the shape of the two galaxies is not distinctly defined.
SN 1982aa, a powerful radio supernova, was detected in NGC 6052.


CID-42

CID-42 (also known as CXOC J100043.1+020637) is a galaxy quasar about 3.9 billion light years away in the constellation Sextans. It is believed to have a supermassive black hole at its center.
Description.
CID-42 is thought to be the result of a galaxy collision between two smaller galaxies. It has a distinctive trail of stars extending many light years.
Black Hole.
The discovery of a potential black hole was made after combining through the data and images taken by several telescopes including NASA's Chandra X-ray Observatory, the Hubble Telescope, the Canada-France-Hawaii Telescope and from the ground-based Magellan and Very Large Telescopes in Chile.
When the two galaxies collided the black holes in their centers collided, forming a single supermassive black hole. The black hole then recoiled from the gravitational waves produced by the merger and is being ejected out of the galaxy at several million miles per hour (~2000 km s−1).
Once ejected it is expected to shine as a displaced quasar for 10 million to 10 billion years until it exhausts its fuel and is no longer recognizable as a quasar.


HD 93833

HD 93833 is a star in the constellation of Sextans. Its apparent magnitude is 5.842, but interstellar dust makes it appear 0.202 magnitudes dimmer than it should be. It is located some 340 light-years (104 parsecs) away, based on parallax.
HD 93833 is a K-type giant star. It has evolved from the main sequence to a radius of 10.5 times that of the Sun. It emits 49.4 times as much energy as the Sun at a surface temperature of 4,720 K.


HD 59686

HD 59686 is a binary star system in the northern constellation of Gemini. It is visible to the naked eye as a dim point of light with an apparent visual magnitude of +5.45. The distance to this system is approximately 292 light years based on parallax, but it is drifting closer with a radial velocity of −34 km/s.
This is a single-lined spectroscopic binary system with an orbital period of and a high eccentricity of 0.73. The visible component is an aging giant star with a stellar classification of K2III, meaning it has ceased fusing hydrogen in its core and on its way to becoming a red giant. The stellar radius is very large: 11.2 times that of our Sun. The star is around 2.7 billion years old with 1.4 times the mass of the Sun. It is radiating 58 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,670 K.
The secondary component has a minimum mass 53% that of the Sun, which indicates it must be a star rather than a brown dwarf or a planet.
Planetary system.
In November 2003, a planet was announced orbiting the giant star. A doppler spectrometer was used to look for effects on the star caused by the gravitational tug of the orbiting planet. Using the amplitude from the radial velocity method, he calculated the planetary mass as 5.25 Jupiter masses and with period 303 days. However that mass is only a minimum because the inclination of the orbit is not known. Using the stellar mass and period, he calculated the semimajor axis as 0.911 astronomical units. He found that the shape of the stellar wobble is circular, implying that the planet has zero eccentricity.


E Velorum

The Bayer designations e Velorum and E Velorum are distinct. Due to , both designations link here. For the star


Delta Draconis

Delta Draconis (δ Draconis, abbreviated Delta Dra, δ Dra), formally named Altais , is a yellow star in the constellation of Draco. It has an apparent visual magnitude of 3.0, making it easily visible to the naked eye. Based on parallax measurements obtained during the Hipparcos mission, it is approximately from the Sun.
Nomenclature.
"δ Draconis" (Latinised to "Delta Draconis") is the star's Bayer designation.
It bore the traditional names "Aldib", "Altais" (the goat) and "Nodus Secundus". The title "Altais" was derived from Arabic "Al Tāis" "the Goat", the association of this star, along with Pi Draconis, Rho Draconis and Epsilon Draconis (Tyl). According to a 1971 NASA catalog of stars, "Al Tāis" or "Tais" were the title for three stars : Delta Draconis as "Altais", Pi Draconis as "Tais I" and Rho Draconis as "Tais II" (exclude Epsilon Draconis). In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalogue and standardize proper names for stars. The WGSN approved the name "Altais" for this star on 21 August 2016 and it is now so included in the List of IAU-approved Star Names.
In Chinese, (), meaning "Celestial Kitchen" or "Heaven's Kitchen", refers to an asterism consisting of Delta Draconis, Sigma Draconis, Epsilon Draconis, Rho Draconis, 64 Draconis and Pi Draconis. Consequently, the Chinese name for Delta Draconis itself is (, ).
Properties.
Delta Draconis is a giant star with a stellar classification of G9 III. This indicates that, at an estimated age of 800 million years, it has exhausted the supply of hydrogen at its core and entered a later stage in its evolution. The angular diameter of the star is estimated as . At a parallax of 32.54 mas, this corresponds to a physical radius equal to 11 times the solar radius. It is radiating 59 times the luminosity of the Sun from its outer atmosphere at an effective temperature of 4,820 K. At this temperature, it is giving off the yellow-hued glow of a G-type star. With a mass 2.32 times that of the Sun, this star will end its life as a white dwarf.
Pole star.
Delta Draconis is the northern pole star of Ceres, lying 1.5 degrees from the true pole.


25 Arietis

25 Arietis is a star in the equatorial constellation of Cetus, near the modern constellation boundary with Aries for which it is named. "25 Arietis" is the Flamsteed designation. It has an apparent visual magnitude of 6.45, placing it near the lower limit of visibility to the naked eye. The distance to this star can be estimated from its annual parallax shift of , which yields a separation of 119 light years. The star is moving closer to the Earth with a heliocentric radial velocity of −40 km/s, and is predicted to come as close as in 259,000 years. It has a relatively high proper motion, traversing the celestial sphere at the rate of per year.
This is an ordinary F-type main-sequence star with a stellar classification of F5 V. It is about 1.6 billion years old with an estimated 1.19 times the mass of the Sun and 1.44 times the Sun's radius. The star is radiating 2.9 times the Sun's luminosity from its photosphere at an effective temperature of around 6,274 K.


Mu Pegasi

Mu Pegasi (μ Pegasi, abbreviated Mu Peg, μ Peg), formally named Sadalbari , is a star in the northern constellation of Pegasus. The apparent visual magnitude of this star is 3.5, which is bright enough to be seen with the naked eye even on a moonlit night. Based upon parallax measurements taken during the Hipparcos mission, it is approximately from the Sun.
Nomenclature.
"μ Pegasi" (Latinised to "Mu Pegasi") is the star's Bayer designation.
It bore the traditional name "Sadalbari", which derives from "saʿd al-bāriʿ", the “auspicious star of the splendid one.” In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalogue and standardize proper names for stars. The WGSN approved the name "Sadalbari" for this star on 21 August 2016 and it is now so included in the List of IAU-approved Star Names.
In Chinese, (), meaning "Resting Palace", refers to an asterism consisting of Mu Pegasi, Lambda Pegasi, Omicron Pegasi, Eta Pegasi, Tau Pegasi and Nu Pegasi. Consequently, the Chinese name for Mu Pegasi itself is (, "the Second Star of Resting Palace").
Properties.
The spectrum of this star matches a stellar classification of G8 III. The luminosity class of 'III' means that it has exhausted the hydrogen fuel at its core and evolved into a giant star. It is slightly more massive than the Sun, but has expanded to nearly ten times the Sun's radius. (Mishenina et al. (2006) list it with an estimated 2.7 times the mass of the Sun.) The effective temperature of the outer atmosphere is about 4,950 K, which is cooler than the Sun and gives it the yellow hue of a G-type star. The abundance of elements other than hydrogen and helium, what astronomers term the metallicity, is similar to the abundance in the Sun.


Eta Piscis Austrini

Eta Piscis Austrini (η Piscis Austrini) is binary star system in the southern constellation of Piscis Austrinus. As of 2000, the two components had an angular separation of 1.818 arc seconds along a position angle of 113.4°. The pair have a combined apparent visual magnitude of +5.43, which is bright enough to be seen with the naked eye. Based upon an annual parallax shift of 3.99 mas as seen from the Earth, the system is located roughly 820 light years from the Sun.
The magnitude 5.7 primary, component A, is a blue-white hued Be star with a stellar classification B8 V. At the age of 115, the star is spinning rapidly with a projected rotational velocity of 265. It has an estimated four times the mass of the Sun and is radiating 604 times the solar luminosity at an effective temperature of 11,272 K. The secondary, component B, has a visual magnitude of 6.8.
Eta Piscis Austrini is moving through the Galaxy at a speed of 11.3 km/s relative to the Sun. Its projected Galactic orbit carries it between 23,600 and 30,800 light years from the center of the Galaxy.


LoTr 5

LoTr 5 is a large, faint planetary nebula in the constellation of Coma Berenices. In 2018, its parallax was measured by "Gaia", giving a distance of about 1,650 light-years (506 parsecs).
As of 2018, LoTr 5 has the highest galactic latitude of any known planetary nebula, being only 1.5 degrees away from the galactic north pole. Scientists noted this because if the distance of the nebula were found to be greater than a few hundred parsecs, then the gas from the nebula would be expanding into the galactic halo, where there is little interaction with the interstellar medium.
Nomenclature.
The nebula is most commonly referred to as LoTr 5, short for Longmore-Tritton 5. It was discovered in 1980 by A. J. Longmore and S. B. Tritton, who found the nebula on photographic plates taken at the UK Schmidt Telescope.
The central star has a number of different names. It is often referred to by its Henry Draper Catalogue designation HD 112313, or by its variable star designation IN Comae Berenices. The General Catalogue of Variable Stars describes it as R:/PN, meaning it is likely a close binary star system with reflection of starlight being the cause of variation, as well as being part of the nucleus of a planetary nebula.
Structure.
LoTr 5 is one of the largest planetary nebulae known, with a radius of 1.8 light-years (0.55 parsecs). It mostly emits light at a wavelength of 500.7 nm, corresponding to a doubly ionized oxygen line.
LoTr 5 is not spherical, but is instead a bipolar nebula. Many bipolar and non-spherical nebulae are known to exist, but it is the processes that cause planetary nebulae to get their shapes are not clear, and have been the subject of much debate. However, the "binary hypothesis" posits that binary stars are more likely to produce non-spherical nebulae. For LoTr 5, the binary system likely played a role in shaping the nebula.
A modelling of LoTr 5 shows that it is composed of two round lobes, making a peanut shape. The semimajor and semiminor axes are about 390 arcsec and 100 arcsec, respectively. The position angle of the long axis is 55°. The long axis is tilted 17° away from the line of sight, so there is considerable overlap between the farther northeastern lobe and the closer southwestern lobe. The nebula is not perfectly symmetrical: there appears to be a "hole" east of the nucleus, while the western side has an "arc" of emission.
Binary system.
The central system at LoTr 5 has been known to be binary since 1983. At the center there is an evolved G-type star (IN Comae Berenices) that is often classified as a giant star or a subgiant, as well as a hot O-type subdwarf or white dwarf that is responsible for ionizing the nebula. The subdwarf is one of the hottest stars known, with an effective temperature of about K.
The two stars orbit each very slowly; in fact, with an orbital period of , this is one of the longest periods for a binary system within a planetary nebula. The orbit is also moderately eccentric, at 0.249 ± 0.018. For a long time the hierarchical structure of the system has not been clear. Earlier studies came up with inner orbits around IN Comae Berenices with periods of 1.95 days or 1.75 days, and/or suggesting a third star orbiting the central G-type star. The central stars' orbit appears to have a discrepancy with the nebula's "waist" such that the nebula's inclination of 17° may be too low. It is also possible, but more unlikely that the stellar orbits are not coplanar with the nebula's "waist", or that there is an undiscovered object in a close orbit with the degenerate star.
IN Comae Berenices is known to be a variable star, with its brightness varying on a cycle that is about 5.9 days long. This corresponds to the rotation period of the star, and the variability is attributed to starspots, making it an RS Canum Venaticorum variable. With Doppler imaging, the starspots were found to be lying at middle latitudes (40-50°), covering 22% of the star's surface, and about 600 K cooler than the rest of the star's surface. Its spectrum shows it to be rich in barium and other "s"-process elements, making it a barium star.
IN Comae Berenices emits X-rays. These X-rays likely come from the star's corona, and are associated with the star's rapid rotation.
In terms of structure, LoTr 5 is very similar to Abell 35, another planetary nebula. Both are large and faint planetary nebulae with a binary nucleus, consisting of a rapidly rotating G-type star that is a rotational variable.


Omega Canis Majoris

Omega Canis Majoris, Latinized from ω Canis Majoris, is a solitary, blue-white-hued star in the equatorial constellation of Canis Major. It is visible to the naked eye with an apparent visual magnitude of +4.01. Based upon an annual parallax shift of just 3.58 mas as seen from Earth, this system is located roughly 910 light-years from the Sun.
This star has a stellar classification of B2 IV-Ve, indicating it is a Be star showing a mixed spectrum of a main sequence star and a subgiant. One of the most observed Be stars of the Southern Hemisphere, Omega Canis Majoris is classified as a Gamma Cassiopeiae-type variable star. Both the luminosity and the radial velocity vary with a primary cyclical period of 1.372 days. The variation in brightness, ranging from magnitude +3.60 to +4.18, shows changes over time, which suggests there are two overlapping periods of 1.37 and 1.49 days. The star also undergoes transient periodicities following outbursts.
This is a massive star with ten times the mass of the Sun and 6.2 times the Sun's radius. At an estimated age of 22.5 million years, it is radiating 13,081 times the Sun's luminosity from its photosphere at an effective temperature of 21,878 K. The star is being viewed nearly pole on, so the measured projected rotational velocity of 80 km/s is only a fraction of the true equatorial velocity, estimated as 350 km/s. It is surrounded by a symmetric circumstellar decretion disk of material that is being heated by the star, which in turn is inserting emission lines into the combined spectrum.


HD 222582 b

HD 222582 b is an extrasolar planet that is 8.37 times the mass of Jupiter orbiting the star HD 222582. The orbital period is 572 days and orbits at a semimajor axis of 1.35 AU in one of the most eccentric orbits of any known planets.


L Puppis

The Bayer designation L Puppis is shared by two stars in the constellation Puppis:
For technical reasons, l Puppis also links here. It is a distinct star:
See also.
j Puppis


Eta Reticuli

Eta Reticuli (Eta Ret, η Reticuli, η Ret) is a solitary star in the southern constellation of Reticulum. With an apparent visual magnitude of 5.22, it is faintly visible to the naked eye on a dark night. Based upon an annual parallax shift of 8.48 mas, it is located at a distance of roughly 385 light years from the Sun. It may be a member of the high-velocity Zeta Herculis Moving Group of stars that share a common motion through space.
This is an evolved G-type giant star with a stellar classification of G7 III. Based upon stellar models, it has an estimated 2.54 times the mass of the Sun and 13.24 times the Sun's radius. With an age of around 1.17 billion years, it is radiating 120 times the solar luminosity from its outer atmosphere at an effective temperature of 4,948 K.
Eta Reticuli is moving through the Galaxy at a speed of 117.6 km/s relative to the Sun. Its projected Galactic orbit carries it between 11,700 and 31,600 light years from the center of the Galaxy.


26 Arietis

26 Arietis is a variable star in the northern constellation of Aries. "26 Arietis" is the Flamsteed designation; it also bears the variable star designation UU Arietis. The apparent visual magnitude of this star is 6.14, which, according to the Bortle Dark-Sky Scale, is within the naked eye visibility limit in dark rural skies. The annual parallax shift of is equivalent to a distance of approximately from Earth. The star is receding from the Earth with a heliocentric radial velocity of +15 km/s.
This is an A-type main sequence star with a stellar classification of A9 V. It is a Delta Scuti variable with a variability period of 0.0676 days and an amplitude of 0.010 in magnitude. The star is around a billion years old with 1.74 times the mass of the Sun and 2.32 times the Sun's radius. The star is radiating 15 times the luminosity of the Sun from its photosphere at an effective temperature of 7,430 K.


Mu Cancri

Mu Cancri (μ Cancri, μ Cnc, Mu Cnc) is the name of several stars
Mu Cancri also sometimes just means Mu2 Cancri.


Epsilon Serpentis

Epsilon Serpentis, Latinized from ε Serpentis, is a single, white-hued star in the constellation Serpens, in its head (Serpens Caput). It is visible to the naked eye with an apparent visual magnitude of +3.69. Based upon an annual parallax shift of 46.30 mas as seen from Earth, it is located 70 light years from the Sun. It is moving closer to the Sun with a radial velocity of −9 km/s.
This is an Am star on the main-sequence with a stellar classification of kA2hA5mA7 V. This notation indicates the spectrum displays the calcium K-line of an A2 star, the hydrogen lines of an A5 star, and the metal lines of an A7 star. It has been examined for the presence of a magnetic field, but the detected level was not statistically significant.
Epsilon Serpentis has an estimated 1.82 times the mass of the Sun and 1.78 times the Sun's radius. The star is radiating 12 times the Sun's luminosity from its photosphere at an effective temperature of around 7,928 K. It is a candidate for an infrared excess at a wavelength of 25 μm, suggesting a circumstellar disk of dust with a temperature of may be orbiting roughly 4.2 AU from the host star. The star is around half a billion years old and is spinning with a projected rotational velocity of 33.1 km/s.
Etymology.
Epsilon Serpentis was a member of indigenous Arabic asterism al-Nasaq al-Yamānī, "the Southern Line" of "al-Nasaqān" "the Two Lines". along with α Ser (Unukalhai), δ Ser, δ Oph (Yed Prior), ε Oph (Yed Posterior), ζ Oph and γ Oph.
According to the catalogue of stars in the "Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars", "al-Nasaq al-Yamānī" or Nasak Yamani were the title for two stars :δ Ser as "Nasak Yamani I" and ε Ser as "Nasak Yamani II" (exclude α Ser, δ Oph, ε Oph, ζ Oph and γ Oph).
In Chinese, (), meaning "Right Wall of Heavenly Market Enclosure", refers to an asterism which is represent eleven old states in China which is marking the right borderline of the enclosure, consisting of ε Serpentis, β Herculis, γ Herculis, κ Herculis, γ Serpentis, β Serpentis, α Serpentis, δ Serpentis, δ Ophiuchi, ε Ophiuchi and ζ Ophiuchi. Consequently, the Chinese name for ε Serpentis itself is (, ), represent the state Ba (巴) (or Pa).


HD 206267

HD 206267A is a hierarchical triple star system in the northern circumpolar constellation of Cepheus. Two of the members form a spectroscopic binary that orbit each other with a period of 3.7 days, while a third member lies further away—it is unclear whether this third member is gravitationally bound to the pair. The system is emitting a stellar wind that reaches an exceptional velocity of 3,225 km/s, among the highest measured for stars of this type.
This stellar system lies in the nebula IC 1396. All three components are massive stars, and the intense ultraviolet radiation they give off ionizes the gas of IC 1396, and causes compression denser globules of the nebula, leading to star formation. The stellar wind produced by the stars is strong enough to strip nearby stars of their protoplanetary disks.
External links.
Mass Proof
https://www.researchgate.net/publication/238537453_The_Components_of_the_HD_206267_A_Triple_Star_System


Gliese 849

Gliese 849, or GJ 849, is a small, solitary star in the equatorial constellation of Aquarius. It has a reddish hue and is invisible to the naked eye with an apparent visual magnitude of 10.41. The distance to this star is 28.7 light years based on parallax, but it is drifting closer to the Sun with a radial velocity of −15.3 km/s. It has a pair of confirmed gas giant companions.
The stellar classification of GJ 849 is M3.5V, which means this is a small red dwarf star generating energy through hydrogen fusion at its core region. Various studies have found super-solar abundances in the spectra, indicating that the elemental abundances of higher mass elements is significantly higher than in the Sun. The star has about half the mass and size of the Sun, and is spinning slowly with a rotation period of approximately 39 days. The estimated age of the star is more than three billion years. It is radiating a mere 2.8% of the luminosity of the Sun from its photosphere at an effective temperature of 3,601 K.
Planetary system.
In late 2006, a long-period Jupiter-like exoplanet was reported to be orbiting the red dwarf in a period just over 5 years in length. There was also a linear trend in the radial velocities which suggested another longer period companion. The trend in the radial velocities was confirmed in 2013. An orbit for the second exoplanet was finally determined in 2015. It is the first planet discovered orbiting a red dwarf with a semi-major axis greater than 0.21 AU.


M Carinae

The Bayer designations m Carinae and M Carinae are distinct.


NGC 6005

NGC 6005 is an open cluster in the constellation Norma. It is 5875 light-years distant and thought to be around 1.15 billion years old.


NGC 6388

NGC 6388 is a globular cluster located in the constellation Scorpius. The cluster was discovered by Scottish astronomer James Dunlop on May 13, 1826 using a reflector telescope. Due to its moderate apparent magnitude (+6.72), a telescope is required to see it.


Rho Hydrae

Rho Hydrae, equally written ρ Hydrae, is a binary star in the equatorial constellation of Hydra. It is visible to the naked eye with an apparent visual magnitude of 4.34. The distance to this system, based upon an annual parallax shift of 9.21 mas, is about 354 light years. At that distance, the visual magnitude is diminished by an interstellar extinction of 0.06 magnitudes, due to intervening dust.
The primary component is an A-type main sequence star with a stellar classification of A0 Vn. It has around double the radius of the Sun and 3.2 times the Sun's mass. Rho Hydrae is around 350 million years old and has a high rate of spin, with a projected rotational velocity of 128 km/s. It radiates 242 times the solar luminosity from its outer atmosphere at an effective temperature of 9,795 K. The companion is a magnitude 11.9 star at an angular separation of 12.1 arc seconds along a position angle of 146°, as of 2000.
Name and etymology.
This system appears among bright stars in a compact pentagon, resembling a quadrilateral due to the suggestive proximity (close arc distance) to Epsilon Hydrae (ε Hya). This shape in the Greco-Roman tradition, which draws on trading and navigation histories shared with nearby older-recorded astrologies is an asterism that represents the head of the water snake.
This light source, along with comparable strength (apparent magnitude) Epsilon, δ Hya (Lisan al Sudja), ζ Hya, η Hya, and σ Hya (Minchir), were Ulug Beg's "Min al Azʽal", "Belonging to the Uninhabited Spot". According to the catalogue of stars in the "Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars", "Min al Azʽal" or "Minazal" were the title for five stars: δ Hya as "Minazal I", η Hya as "Minazal II", ε Hya as "Minazal III", ρ Hya as "Minazal IV" and ζ Hya as "Minazal V" (exclude σ Hya).
In Chinese, (), meaning "Willow", refers to an asterism consisting of ρ Hydrae, δ Hydra, σ Hydrae, η Hydrae, ε Hydrae, ζ Hydrae, ω Hydrae and θ Hydrae Consequently, ρ Hydrae itself is known as (, ).
The people of Groote Eylandt called "Unwala", "The Crab", for the star cluster including this star, δ Hya (Lisan al Sudja), ε Hya, η Hya, ζ Hya and σ Hya (Minchir).


28 Vulpeculae

28 Vulpeculae is a single star in the northern constellation of Vulpecula. It lies approximately 560 light years away and is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude of 5.047. The star is moving closer to the Sun with a heliocentric radial velocity of −23 km/s, and may come as close as in 5.9 million years.
This is a subgiant star with a spectral class of B5 IV, indicating a hot massive star that has started to evolve away from the main sequence after exhausting it core hydrogen. It has been included in a list of the least variable stars observed with the Hipparcos satellite; its brightness varied by no more than 0.0005 magnitudes in the Hipparcos passband. The star has five times the mass of the Sun and is spinning rapidly with a projected rotational velocity of 285 km/s. It is radiating 713 times the Sun's luminosity from its photosphere at an effective temperature of 15,200 K.


V424 Lacertae

V424 Lacertae (V424 Lac) is a red supergiant variable star in the constellation Lacerta. It is a member of the Lacerta OB1 stellar association.
The MK spectral type of V424 Lac has been determined to be K5, but it has also been classified as M0. It was discovered to be slightly variable using analysis of Hipparcos photometry. The total range is less than a tenth of a magnitude. Multiple short periods are detected, as well as slow variations with a period of 1,100 or 1,601 days. Although listed in the General Catalogue of Variable Stars as a slow irregular variable, it has been considered to be either a semiregular variable or long secondary period variable.
There is an ultraviolet excess from V424 Lacertae, that may be due to an unseen companion, which could also explain the long secondary period. On this assumption, a sub-stellar companion in a 1,382 day 6.2 AU orbit has been suggested.


SV Vulpeculae

SV Vulpeculae is a Classical Cepheid (δ Cepheid) variable star in the constellation Vulpecula. It is a supergiant at a distance of 8,700 light years.
SV Vulpeculae is a δ Cepheid variable whose visual apparent magnitude ranges from 6.72 to 7.79 over 45.0121 days. The light curve is highly asymmetric, with the rise from minimum to maximum taking more less than a third of the time for the fall from maximum to minimum. The period has been decreasing on average by 214 seconds/year.
SV Vulpeculae is a yellow bright supergiant around twenty thousand times as luminous as the sun, with a spectral type that varies from late F to early K. It pulsates and varies in temperature from below 5,000 K to above 6,000 K. The radius is at maximum, and varies from to as the star pulsates.
The mass of SV Vulpeculae is now near , and is estimated to have been about when it was on the main sequence. The rate of change of the period and the atmospheric abundances show that the star is crossing the instability strip for the second time. The first instability strip crossing occurs rapidly during the transition from the main sequence to becoming a red supergiant. The second crossing occurs during core helium burning when the star executes a blue loop, becoming hotter for a time before returning to the red supergiant stage.


Tau7 Serpentis

Tau7 Serpentis, Latinized from τ7 Serpentis, is an A-type star in the constellation of Serpens, approximately 174 light-years from the Earth. It has an apparent visual magnitude of approximately 5.804.


Gamma Piscis Austrini

Gamma Piscis Austrini (γ Piscis Austrini) is binary star system in the southern constellation of Piscis Austrinus. It is visible to the naked eye with a combined apparent visual magnitude of +4.448. As of 2010, the pair had an angular separation of 4 arc seconds along a position angle of 255°. Based upon an annual parallax shift of 15.14 mas as seen from the Earth, the system is located about 215 light years from the Sun.
The magnitude 4.59 primary, component A, is a white-hued, chemically peculiar A-type main sequence star with a stellar classification of . It is an estimated 214 million years old with 2.63 times the mass of the Sun. The fainter magnitude 8.20 companion, component B, is an F-type main sequence star with a class of F5 V.
Gamma Piscis Austrini is moving through the Galaxy at a speed of 24.1 km/s relative to the Sun. Its projected Galactic orbit carries it between 21,600 and 30,800 light years from the center of the Galaxy. It came closest to the Sun 1.8 million years ago when it had brightened to magnitude 3.78 from a distance of 157 light years.
Naming.
In Chinese, (), meaning "Decayed Mortar", refers to an asterism consisting of refers to an asterism consisting of γ Piscis Austrini, γ Gruis, λ Gruis and 19 Piscis Austrini. Consequently, the Chinese name for γ Piscis Austrini itself is (, .)


HD 73256

HD 73256 is a variable star in the southern constellation of Pyxis. It has the variable star designation CS Pyxidis. With a baseline apparent visual magnitude of 8.08, it requires a small telescope to view. The star is located at a distance of 120 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +30 km/s.
The stellar classification of this star is G8IV-VFe+0.5, which suggests a slightly evolved G-type main-sequence star with a mild overabundance of iron in the spectrum. It is a BY Draconis variable with a period of 13.97 days, showing a variation of 0.03 in magnitude due to chromospheric activity. The star appears overluminous for its class, which may be the result of a high metallicity. The star has roughly the same mass and a slightly smaller radius as the Sun, but is radiating 74% of the Sun's luminosity. It is around 2–3 billion years old and is spinning with a projected rotational velocity of 3.2 km/s.
In 2003, S. Udry and colleagues reported the discovery of a planet in orbit around HD 73256 using data from the CORALIE spectrograph. This object is a Hot Jupiter with at least 1.87 times the mass of Jupiter in an orbit with a period of 2.55 days. In 2018, K. Ment and colleagues reported an attempt to confirm the existence of this planet using Keck/HIRES data, but were unable to do so. Thus the existence of this object is disputed.


Pi Fornacis

π Fornacis (Latinised as Pi Fornacis) is the Bayer designation for a binary star system in the southern constellation of Fornax. It has an apparent visual magnitude of 5.360, which is bright enough to be seen with the naked eye on a dark night. With an annual parallax shift of 11.08 mas, it is estimated to lie around 294 light years from the Sun. At that distance, the visual magnitude is diminished by an interstellar absorption factor of 0.10 due to dust.
This system is a member of the thin disk population of the Milky Way galaxy. The primary, component A, is an evolved G-type giant star with a stellar classification of G8 III. It has an estimated mass slightly higher than the Sun, but has expanded to more than nine times the Sun's radius. The star is roughly five billion years old and is spinning slowly with a projected rotational velocity of 0.9 km/s. Pi Fornacis A radiates 57.5 times the solar luminosity from its outer atmosphere at an effective temperature of 5,048 K.
A companion, component B, was discovered in 2008 using the AMBER instrument of the Very Large Telescope facility. At the time of discovery, this star lay at an estimated angular separation of from the primary along a position angle of . The preliminary orbital period for the pair is 11.4 years, and the semimajor axis is at least 70 mas. The orbit is highly inclined to the line of sight from the Earth.


Omega Orionis

Omega Orionis (ω Ori) is a star in the constellation Orion. Its apparent magnitude is 4.57 and is located approximately 1,400 light-years from our solar system. It is surrounded by a cloud of dust, forming a modest reflection nebula over a light-year wide.
Omega Orionis is a B-type main sequence star of spectral type B3 Ve with an effective temperature of 19,000 K. Including a large amount of ultraviolet radiation, Omega Orionis shines with a Luminosity 6,031 times greater than the Sun's and it has a radius 5.9 times larger than solar radius, The projected rotation speed is 179 km/s – involves a period of 1.37 days rotation. However, actual rotation speed can reach 450 km/s, it estimated that its axis is inclined 24° relative to the line of sight. The star has a mass 7.0 times that of the Sun, just below the limit beyond which stars explode as supernovas. Its age is estimated at 43.6 million years.
As a result of its rapid rotation, Omega Orionis is a Be class star. Among the stars of this class, Omega Orionis was the first where the magnetic field was measured and found to be 1000 times that of the Earth. Omega Orionis is, like many Be stars, a variable star whose brightness varies 0.19 magnitudes. Also, small variations have been observed due to non-radial pulsations with periods of 0.97 and 2.19 days.


HIP 70849

HIP 70849 is a 10th magnitude K-type main sequence star located approximately 78 light years away in the constellation Lupus. This star, which resembles a brighter red dwarf, is smaller, cooler, dimmer, and less massive than our Sun. In 2009, a gas giant planet/brown dwarf was found in orbit around it.
There is also a potential T4.5 brown dwarf companion orbiting ~9000AU from HIP 70849.
Planetary system.
HIP 70849 b is an extrasolar planet orbiting the star. It has more than five times the mass of Jupiter and takes more than 3000 days to orbit at a semimajor axis of more than 3.5 AU.


Lambda Ceti

Lambda Ceti, Latinized from λ Ceti, is B-type star of fifth-magnitude located in the constellation Cetus. Historically, the star bore the traditional name Menkar, although today that name is more commonly associated with α Ceti.
This star, along with α Cet (Menkar), γ Cet (Kaffaljidhma), δ Cet, μ Cet, ξ1 Cet and ξ2 Cet were "Al Kaff al Jidhmah", "the Part of a Hand".
In Chinese, (), meaning "Circular Celestial Granary", refers to an asterism consisting of λ Ceti, α Ceti, κ1 Ceti, μ Ceti, ξ1 Ceti, ξ2 Ceti, ν Ceti, γ Ceti, δ Ceti, 75 Ceti, 70 Ceti, 63 Ceti and 66 Ceti. Consequently, the Chinese name for λ Ceti itself is (, .)
Properties.
Lambda Ceti is a blue giant star with stellar classification B6III. With a mass between and an estimated radius that is , the star radiates a bolometric luminosity of about . In 1997 the Hipparcos satellite estimated its parallax at 7.69 ± 0.76 milliarcseconds yielding a distance from Earth of about 130 ± 10 parsecs or 420 ± 40 light years. However recent astrometric calculations by van Leeuwen have placed the distance much farther at about 177 ± 7 pc or 580 ± 20 ly—a revaluation which significantly altered other stellar parameters. Its apparent magnitude has been recently recalibrated at 4.6767 yielding an absolute magnitude of -1.56, almost as bright as its neighbor Alpha Ceti at -1.62.


Nu Ceti

ν Ceti, Latinized as Nu Ceti, is a binary star system in the equatorial constellation of Cetus. It is visible to the naked eye as a faint point of light with a combined apparent visual magnitude of 4.86. The system is located approximately 340 light years distant from the Sun, based on parallax, and is drifting further away with a radial velocity of 4.8 km/s. Nu Ceti is believed to be part of the Ursa Major stream of co-moving stars.
In Chinese, (), meaning "Circular Celestial Granary", refers to an asterism consisting of α Ceti, κ1 Ceti, λ Ceti, μ Ceti, ξ1 Ceti, ξ2 Ceti, ν Ceti, γ Ceti, δ Ceti, 75 Ceti, 70 Ceti, 63 Ceti and 66 Ceti. Consequently, the Chinese name for ν Ceti itself is "the Seventh Star of Circular Celestial Granary", .
The primary, designated component A, forms a single-lined spectroscopic binary with an orbital period of and an eccentricity of 0.27. The visible component is a G-type giant star, currently on the horizontal branch, with a stellar classification of G8III. In addition to the spectroscopic companion there is a visual companion star which shares a common proper motion with Nu Ceti A, designated component B; an F-type main-sequence star with a class of F7V and a 9.08 apparent visual magnitude located 8.0 arcsec away. It was discovered by Struve.


HD 36780

HD 36780 is a star located in Orion's belt, within the equatorial constellation of Orion. It has an orange hue and is dimly visible to the naked eye with an apparent visual magnitude of +5.92. The distance to this object is approximately 534 light years based on parallax. It is drifting away from the Sun with a radial velocity of 84 km/s, having come to within some 2.1 million years ago.
This is an aging giant star with a stellar classification of K4 III. After exhausting the supply of hydrogen at its core, the star cooled and expanded off the main sequence. At present it has around 31 times the girth of the Sun. It is radiating 243 times the luminosity of the Sun from its swollen photosphere at an effective temperature of 4,108 K.


NGC 5624

NGC 5624 is a spiral galaxy in the Boötes constellation.


NGC 372

NGC 372 is a triple star located in the constellation Pisces. It was discovered on December 12, 1876 by Dreyer, who described it as "stellar, much brighter middle, mottled but not resolved."


UGC 6093

UGC 6093 is a barred spiral galaxy located approximately 500 million light years (or about 153 megaparsecs) away from Earth in the constellation of Leo.
This galaxy is known to host an active galactic nucleus, which is caused by the accretion of matter by a supermassive black hole located at its center, thus causing it to emit huge amounts of radiation and making UGC 6093's core shine excessively. This galaxy is also a megamaser, which means that it acts as a giant astronomical laser generating microwaves rather than visible light.


Westerhout 49

In astronomy Westerhout 49 also known as W49, is a strong galactic thermal radio source characteristic of an HII region. It was discovered by Gart Westerhout in 1958.
Its distance is estimated to be about 11.1 kpcs or 36,000 light years. and it lies in the galactic plane about the same distance from the galactic centre as does the Sun. It has been compared to the giant HII region NGC 3603 which is about half as distant. Non-thermal radiation has been found which is believed to be from an old supernova remnant. Gaseous molecular outflows have been detected as well as H2O (water) masers . No optical counterpart has yet been discovered. While this is partly due to interstellar absorption, any tight clustering of stars at such a great distance in the galactic plane would be scarcely distinguishable from the general background.
A study published in 2014, where the VLT has been used among other instruments, shows the presence of a very massive star in the central cluster of this star-forming region. The parameters of said star ("W49nr1") are so far poorly constrained, but a luminosity of several million times that of the Sun is estimated as well as an initial mass between 100 and 180 solar masses, and perhaps even more, what would place it among both the most luminous and massive stars known.


NGC 6342

NGC 6342 is a globular cluster located in the constellation Ophiuchus. Its Shapley–Sawyer Concentration Class is IV, and was discovered by the German-born British astronomer William Herschel on 28 May 1786. It is at a distance of 28,000 light years away from earth.
The NGC 6342 is classified as metal-rich, yet have only one generation of stars.


Psi Cancri

The Bayer designation Psi Cancri (ψ Cnc, ψ Cancri) is shared by two star systems, separated by 0.34° on the sky, in the constellation Cancer:


S Arae

S Arae (S Ara) is an RR Lyrae-type pulsating variable star in the constellation of Ara. It has an apparent visual magnitude which varies between 9.92 and 11.24, and it exhibits the Blazhko effect.


Mu Telescopii

Mu Telescopii (μ Telescopii) is a yellow-white hued star in the southern constellation of Telescopium. With an apparent visual magnitude of +6.30, it is near the limit of stars that can be viewed with the naked eye. Based upon an annual parallax shift of 20.18 mas as seen from Earth, it is located around 162 light years from the Sun.
This is an F-type main sequence star with a stellar classification of F5 V. It is chromospherically active. The star is about 2.3 billion years old with 1.3 times the mass of the Sun. It is radiating three times the solar luminosity from its photosphere at an effective temperature of 6,542 K.


HD 70060

HD 70060 is a class A8V (white main-sequence) star in the constellation Puppis. Its apparent magnitude is 4.45 and it is approximately 93.4 light years away based on parallax.


K2-58

K2-58 (also designated as EPIC 206026904) is G-type main-sequence star. The planetary system has three confirmed exoplanets (named as K2-58 b, K2-58 c, K2-58 d).


60 Aurigae

60 Aurigae is a binary star system in the northern constellation of Auriga. The pair have a combined apparent visual magnitude of 6.319 and, based upon parallax measurements, they are approximately distant from the Earth.
The combined spectrum of the pair match a stellar classification of F5 V. The primary component may be an A-type star with an apparent magnitude of
6.47, while the fainter, 8.96 magnitude secondary is possibly a G-type star. The pair orbit each other with a period of 271.1 years at an angular separation of 0.793 arcseconds.
Nomenclature.
60 Aurigae is the Flamsteed designation of this star, also catalogued as HR 2541 and HD 50037. The designation "60 Aurigae" has sometimes been identified with Psi8 Aurigae however Simbad lists Psi8 Aurigae as 61 Aurigae.


V520 Carinae

V520 Carinae is a single star in the southern constellation of Carina. It has the Bayer designation "w Carinae", while "V520 Carinae" is a variable star designation. The star has an orange hue and is faintly visible to the naked eye with an apparent visual magnitude that fluctuates around +4.58. It is located at a distance of approximately 1,140 light years from the Sun based on parallax, and it is drifting further away with a radial velocity of +9 km/s. It is a candidate member of the IC 2391 moving group of co-moving stars.
This is an aging giant star with a stellar classification of K4III, although Humphreys (1970) found a supergiant class of K3Ib. It is a suspected slow irregular variable of type Lc and its brightness varies from magnitude +4.50 to +4.59 with no periodicity. The star now has 131 times the girth of the Sun, having exhausted the supply of hydrogen at its core then cooled and expanded. Comparison with theoretical evolutionary tracks suggests it is 33 million years old with 7.9 times the mass of the Sun, although analysis of its motion suggests it may be an astrometric binary with a mass of . The star is radiating 3,600 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 3,903 K.


Upsilon Leonis

Upsilon Leonis (υ Leo) is a star in the zodiac constellation of Leo. It is visible to the naked eye with an apparent visual magnitude of 4.33. The distance to this star, as determined using parallax measurements, is about 182 light years. At that distance, the visual magnitude of the star is diminished by an estimated extinction factor of 0m.02 because of interstellar dust.
With an age of around 4 billion years, this star has evolved into a G-type giant star with a stellar classification of G9 III. It has 2.6 times the Sun's mass, but has expanded to 11 times the solar radius and shines with 56 times the luminosity of the Sun at an effective temperature of 4,842 K. The rate of rotation is too small to be measured, with a projected rotational velocity of 0.0 km/s. The chemical abundance of elements other than hydrogen and helium, what astronomers term the star's metallicity, is less than half that in the Sun. It is most likely a member of the galactic thin disk population.


Psi Capricorni

Psi Capricorni, Latinized from ψ Capricorni, is a single star in the southern zodiac constellation of Capricornus. It is a yellow-white hued star that is faintly visible to the naked eye with an apparent visual magnitude of +4.13. The distance to this star is approximately 47.9 light years based on parallax measurements, and it is drifting further away with a radial velocity of +20 km/s. The closest approach to the Sun occurred some 467,000 years ago at a separation of .
This object is an F-type main-sequence star with a stellar classification of F5 V/ It is 1.4 billion years old with 1.4 times the mass of the Sun. The measured rotational velocity of this star is approximately 41 km/s (the Sun has an equatorial rotation velocity of 2 km/s). Analysis of the line profile of the star's spectrum indicates that it is undergoing differential rotation, with the variation by latitude being similar to the Sun. The star has 1.5 times the Sun's radius and is radiating 3.8 times the luminosity of the Sun from its photosphere at an effective temperature of 6,572 K. It displays an infrared excess, suggesting the presence of an orbiting debris disk at a separation of and a temperature of 60 K.
Chinese name.
In Chinese, (), meaning "Celestial Farmland", refers to an asterism consisting of ψ Capricorni, ω Capricorni, 3 Piscis Austrini, and 24 Capricorni. Consequently, the Chinese name for ω Capricorni itself is (, ).
In R. H. Allen's version, this star represented the state Yue.


HD 24496

HD 24496 is a binary star system in the equatorial constellation of Taurus. The combined apparent visual magnitude of the pair is 6.81, which is too faint to be readily visible to the normal human eye. The system is located at a distance of 66.8 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +19 km/s. It is traversing the celestial sphere with a proper motion of per year.
The magnitude 6.9 primary star, designated component A, is a G-type main-sequence star with a stellar classification of G7V. It is around three billion years old with a low projected rotational velocity. The star has 96% of the mass of the Sun and 91% of the Sun's radius. The metallicity, what astronomers term the abundance of heavier elements, is about the same as in the Sun. The star is radiating 71% of the luminosity of the Sun from its photosphere at an effective temperature of 5,572 K.
The secondary companion, component B, is a magnitude 11.1 red dwarf of class M2V that shares a common proper motion with the primary. They have an angular separation of along a position angle of 256°, which is equivalent to a physical projected separation of . Their orbital period is around 123,000 years.


HR 7722 c

HR 7722 c is an exoplanet orbiting the star HD 192310 (HR 7722) which is about 29 light years away in the far south-west of Capricornus. It is a Neptune-sized planet and was discovered on 17 August 2011 by the HARPS program.
The planet has a mass of ≥24 ± 5 Earth masses () and orbits its parent star at a semimajor axis of 1.18 ± 0.025 AU, an eccentricity of 0.32 ± 0.11, and in 525.8 ± 9.2 days. Its orbit lies mainly beyond HR 7722's habitable zone, meaning it is too cold to support directly analogous advanced known life, but due to its elliptical orbit, passes into the habitable zone briefly each orbit.


Kappa2 Ceti

 Kappa2 Ceti (κ2 Ceti), is a solitary, yellow-hued star located in the equatorial constellation of Cetus. It is faintly visible to the naked eye with an apparent visual magnitude of 5.66. Based upon an annual parallax shift of 10.11 mas as seen from Earth, it is located about 320 light years from the Sun.
This is an evolved G-type giant star with a stellar classification of G8 III. It is a red clump star on the horizontal branch, which indicates it is generating energy through helium fusion at its core. The star has 2.46 times the mass of the Sun and has expanded to 8.2 times the Sun's radius. It is radiating 42 times the solar luminosity from its photosphere at an effective temperature of 5,007 K.


69 Ceti

69 Ceti is a single star located around 860 light years away in the equatorial constellation of Cetus. It is visible to the naked eye with an apparent visual magnitude of 5.3. This is an aging red giant star with a stellar classification of M1/2III. It is radiating 1,813 times the Sun's luminosity from an enlarged photosphere, 100 times the Sun's radius, at an effective temperature of 3,765 K.


Iota Lupi

ι Lupi, Latinised as Iota Lupi, is a solitary star in the southern constellation of Lupus. It is visible to the naked eye with an apparent visual magnitude of 3.54. Based upon an annual parallax shift of 9.65 mas as seen from Earth, it is located around 338 light years from the Sun. At that distance, the visual magnitude of the star is diminished by an extinction factor of 0.23 due to interstellar dust. Relative to its neighbors, this star has a peculiar velocity of . It appears to be a member of the Scorpio-Centaurus OB association.
This star has the spectrum of a B-type subgiant star with a stellar classification of B2.5 IV, which may indicate that it has used up its core supply of hydrogen and has begun to expand off the main-sequence. It is rotating rapidly with a projected rotational velocity of 370 km/s. This is giving the star an oblate shape with an equatorial bulge that is an estimated 12% larger than the polar radius. It is about 20 million years old with 6.9 times the mass of the Sun and 4 times the Sun's radius. The star radiates 2,082 times the solar luminosity from its outer atmosphere at an effective temperature of 18,605 K.


Ophiuchus Supercluster eruption

According to NASA and others, the Ophiuchus Supercluster eruption was the biggest AGN outburst seen in the observable universe since the MS 0735+74 outburst.
This extremely powerful eruption occurred in the Ophiuchus Supercluster, which is located about 390 million light-years from Earth. A paper describing these results appeared online on 27 February 2020 in The Astrophysical Journal, and a preprint is available on arXiv. This eruption was caused by a supermassive black hole spraying out jets of extremely active particles over hundreds of millions of years. The total energy which was slowly released over hundreds of millions of years is estimated to be 5 × 1061 erg, or 5 × 1054 J, but it's likely an underestimate, given uncertainty of cavities's size and difficulties of part of them to be discovered.
Furthermore, the cavity produced by the outburst is so big that would be possible to put 15 galaxies of Milky Way's dimensions in a row.
The authors of this paper are Simona Giancintucci (Naval Research Laboratory, Washington, DC), Maxim Markevitch (Goddard Space Flight Center, Greenbelt, Maryland), Melanie Johnston-Hollitt (International Centre for Radio Astronomy, Australia), Daniel Wik (University of Utah), Qian Wang (University of Utah), and Tracy Clarke (Naval Research Laboratory). The 2016 paper by Norbert Werner et al. was published in the Monthly Notices of the Royal Astronomical Society.
This observation is a result of collaboration among various space-based and Earth-based observatories including the Hubble Space Telescope, the Chandra X-ray Observatory, ESA’s XMM Newton X-ray space observatory and radio data from the Murchison Widefield Array (MWA) in Australia and the Giant Metrewave Radio Telescope (GMRT) in India.


QZ Puppis

QZ Puppis (QZ Pup, b Pup) is a class B2.5V (blue main-sequence) star in the constellation Puppis. Its apparent magnitude is 4.49 and it is approximately 650 light years away based on parallax.
It is an ellipsoidal variable, ranging from 4.54 to 4.47 magnitude, with a reported period of 1.1 days.


Beta Sagittarii

Beta Sagittarii (β Sagittarii, abbreviated Beta Sgr, β Sgr) is the common designation shared by two star systems in the constellation of Sagittarius, themselves designated β1 Sagittarii (itself a probable binary star) and β2 Sagittarii. The two systems are separated by 0.36° in the sky.
β1 Sagittarii's two components are designated β1 Sagittarii A, also named Arkab Prior, and β1 Sagittarii B (sometimes designated Arkab Prior A and B). β2 Sagittarii is named Arkab Posterior. Beta Sagittarii is also referred to by the traditional name Arkab.
Nomenclature.
"β Sagittarii" (Latinised to "Beta Sagittariii") is the groups's Bayer designation; "β1" and "β2 Sagittarii", those of its two constituents. The designations of "β1's" components - "β1 Sagittarii A" and "B" - derive from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the International Astronomical Union (IAU).
The system's traditional name "Arkab" derives from the Arabic عرقوب "carqūb" meaning "Achilles Tendon". The two constituents bore the traditional names "Arkab Prior" and "Arkab Posterior" since "β1" leads "β2" (or "β2" follows "β1") across the sky. In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalogue and standardize proper names for stars. The WGSN states that in the case of multiple stars the name should be understood to be attributed to the brightest component by visual brightness. The WGSN approved the names "Arkab Prior" and "Arkab Posterior" for "β1 Sagittarii A" and "β2 Sagittarii" on 5 October 2016 and they are now so entered in the IAU Catalog of Star Names.
"β1" and "β2 Sagittarii", together with Alpha Sagittarii, were "Al Ṣuradain" (الصردين), the two "Surad", "desert birds".
In Chinese, (), meaning "Celestial Spring", refers to an asterism consisting of β1 Sagittarii, β2 Sagittarii, and Alpha Sagittarii, Consequently, β1 and β2 Sagittarii themselves are known as (, .) and (, .)
Namesakes.
USS Arkab (AK-130) was a United States Navy Crater class cargo ship named after the system.


Eta Eridani

Eta Eridani (η Eridani, abbreviated Eta Eri, η Eri), officially named Azha (with a silent 'h', possibly ), is a giant star in the constellation of Eridanus. Based on parallax measurements taken during the Hipparcos mission, it is approximately 137 light-years from the Sun.
Nomenclature.
"η Eridani" (Latinised to "Eta Eridani") is the star's Bayer designation.
It bore the traditional name "Azha", from the old Arab asterism نَعَام أُدْحِيّ "udḥiyy al-naʽām" "the ostrich nest" (or "hatching place"), which included Eta Eridani. The first word, ادحى "udḥiyy", was miscopied as ازحى (readable as "azḥā") in medieval manuscripts.
In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalogue and standardize proper names for stars. The WGSN approved the name "Azha" for this star on 12 September 2016 and it is now so included in the List of IAU-approved Star Names.
In Chinese, (), meaning "Celestial Meadows", refers to an asterism consisting of Eta Eridani, Gamma Eridani, Pi Eridani, Delta Eridani, Epsilon Eridani, Zeta Eridani, Pi Ceti, Tau1 Eridani, Tau2 Eridani, Tau3 Eridani, Tau4 Eridani, Tau5 Eridani, Tau6 Eridani, Tau7 Eridani, Tau8 Eridani and Tau9 Eridani. Consequently, the Chinese name for Eta Eridani itself is (, ).
Properties.
η Eridani belongs to spectral class K3 and has a giant luminosity class. It is an evolved star that has expanded to tens times the size of the sun and nearly sixty times its luminosity. It is red clump giant, a star slightly more massive than the sun which is currently fusing helium in its core. This is a mild barium star, sometimes referred to a "semi-barium" star. Although most barium stars are in binary systems, η Eridani has no known companion.
η Eridani is a high proper motion star, a relatively close star that is moving across the sky at a high rate compared to most stars. It is suspected to be a variable star with a range from magnitude 3.81 to 3.90.


Kappa Capricorni

Kappa Capricorni (κ Cap, κ Capricorni) is a solitary star in the constellation Capricornus. It is visible to the naked eye with an apparent visual magnitude of +4.73. Based upon an annual parallax shift of 11.09 mas as seen from the Earth, the star is located about 294 light years from the Sun.
This is a yellow-hued, evolved, G-type giant star with a stellar classification of G8 III. There is a 91% probability that it is currently on the horizontal branch, rather than the red giant branch. As such, it is a red clump giant with an estimated 2.43 times the mass of the Sun and has expanded to 13.28 times the radius of the Sun. The star is about 1.2 billion years old and has a projected rotational velocity that is too small to be measured. It radiates 107 times the solar luminosity from its photosphere at an effective temperature of 5,096 K.


NGC 470

NGC 470 is a spiral galaxy in the constellation Pisces. Its distance being approximately 91 million lightyears from earth, it was discovered by Friedrich Wilhelm Herschel in 1784. The galaxy also weakly interacts with NGC 474.


Beta Centauri

Beta Centauri (Latinised from β Centauri, abbreviated Beta Cen, β Cen), officially called Hadar , is a triple star system in the southern constellation of Centaurus. The system's combined apparent visual magnitude of 0.61 makes it the second-brightest object in Centaurus and one of the brightest stars in the night sky. According to parallax measurements from the astrometric Hipparcos satellite, the distance to this system is about .
Nomenclature.
"β Centauri" (Latinised to "Beta Centauri") is the star system's Bayer designation.
It bore the traditional names "Hadar" and "Agena". "Hadar" comes from the Arabic حضار (the root's meaning is "to be present" or "on the ground" or "settled, civilized area"), while the name "Agena" is thought to be derived from the Latin "genua", meaning "knees", from the star's position on the left knee of the centaur depicted in the constellation Centaurus. In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalog and standardize proper names for stars. The WGSN approved the name "Hadar" for the star β Centauri Aa on 21 August 2016 and it is now so entered in the IAU Catalog of Star Names.
The Chinese name for the star is 马腹一 (Mandarin: mǎ fù yī, "the First Star of the Horse's Abdomen").
The indigenous Boorong people of what is now northwestern Victoria, Australia named it as "Bermbermgle" (together with α Centauri), two brothers who were noted for their courage and destructiveness, and who spear and kill Tchingal, "The Emu" (Coalsack Nebula). The Wotjobaluk people name the two brothers "Bram-bram-bult".
Visibility.
Beta Centauri is one of the brightest stars in the sky at magnitude 0.61. Its brightness varies by a few hundredths of a magnitude, too small to be noticeable to the naked eye. Because of its spectral type and the detection of pulsations, it has been classified as a β Cephei variable.
Beta Centauri is well known in the Southern Hemisphere as the inner of the two "Pointers" to the constellation Crux, popularly known as the Southern Cross. A line made from the other pointer, Alpha Centauri, through Beta Centauri leads to within a few degrees of Gacrux, the star at the north end of the cross. Using Gacrux, a navigator can draw a line with Acrux at the south end to effectively determine south.
Stellar system.
The Beta Centauri system is made up of three stars: Beta Centauri Aa, Beta Centauri Ab, and Beta Centauri B. All the spectral lines detected are consistent with a B1 type star, with only the line profiles varying, so it is thought that all three stars have the same spectral type.
In 1935, Joan Voûte identified Beta Centauri B, giving it the identifier VOU 31. The companion is separated from the primary by 1.3 seconds of arc, and has remained so since the discovery, although the position angle has changed six degrees since. Beta Centauri B is a B1 dwarf with an apparent magnitude of 4.
In 1967, Beta Centauri's observed periodic variation in radial velocity suggested that Beta Centauri A is a double-lined spectroscopic binary. This was confirmed in 1999. The primary consists of a pair of stars, β Centauri Aa and β Centauri Ab, of similar mass that orbit each other over a period of 357 days with a large eccentricity of about 0.8245.
The pair were calculated to be separated by a mean distance of roughly 4 astronomical units (based on a distance to the system of 161 parsecs) in 2005.
Both Aa and Ab apparently have a stellar classification of B1 III, with the luminosity class of III indicating giant stars that are evolving away from the main sequence. Component Aa rotates much more rapidly than Ab, causing its spectral lines to be broader, and so the two components can be distinguished in the spectrum. Component Ab, the slow-rotating star, has a strong magnetic field although no detected abundance peculiarities in its spectrum. Multiple pulsations modes have been detected in component Aa, some of which correspond to brightness variations, so this star is considered to be variable. The detected pulsation modes correspond to those for both and β Cephei variables and slowly pulsating B stars. Similar pulsations have not been detected in component Ab, but it is possible that it is also a variable star.
Aa is 12.02 ± 0.13 times as massive as the Sun, while Ab is 10.58 ± 0.18 times as massive.


NGC 443

NGC 443 is a lenticular galaxy of type S0/(r)a? located in the constellation Pisces. It was first discovered on October 8, 1861 by Heinrich d'Arrest (and later listed as NGC 443), and was also spotted on October 17, 1903 by Stéphane Javelle (and later listed as IC 1653). It was described by Dreyer as "faint, small, round, 15th magnitude star 8 seconds of time to west on parallel (that is, at the same declination)."


V420 Aurigae

V420 Aurigae is a high-mass star with an inferred compact companion. Closely orbiting each other every 0.8 days, they are a source of X-ray emission.


HD 73390

HD 73390, also called e1 Carinae, is a binary star system in the constellation Carina. It is approximately 870 light years from Earth. The primary is a blue-white B-type main sequence dwarf with an apparent magnitude of +5.27. It displays an infrared excess and is a candidate host of an orbiting debris disk. The secondary is a magnitude 8.9 star which has a mass and temperature similar to the Sun.


Upsilon Puppis

The Bayer designation υ Puppis (Upsilon Puppis) is shared by two stars in the constellation Puppis:


5 Canum Venaticorum

5 Canum Venaticorum is a probable binary star system in the northern constellation of Canes Venatici, located about 375 light years from the Sun. It is visible to the naked eye as a faint, yellow-hued star with an apparent visual magnitude of +4.77. The system is moving closer to the Earth with a heliocentric radial velocity of −14 km/s.
The visible component is an evolved G-type giant star with a stellar classification of . The 'Ba0.3' suffix notation indicates this is a mild barium star, which means that the stellar atmosphere has been enhanced by s-process elements most likely provided by what is now an orbiting white dwarf companion. The primary is 530 million years old with 2.96 times the mass of the Sun and has expanded to about 12 times the Sun's radius. It is radiating 174 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 5,098 K.
In Chinese astronomy, 5 Canum Venaticorum is called 相, Pinyin: Xiāng, meaning "Prime Minister", because this star is marking itself and stand alone in "Prime Minister" asterism, Purple Forbidden enclosure mansion (see : Chinese constellation).


Cygnus X (star complex)

Cygnus-X is a massive star formation region located in the constellation of Cygnus at a distance from the Sun of 1.4 kiloparsecs (4,600 light years).
As it is located behind the Cygnus Rift and its light is heavily absorbed by Milky Way's interstellar dust, it is better studied in other wavelengths of the electromagnetic spectrum that penetrate it such as the infrared.
Physical properties.
As studies done with the help of the Spitzer Space Telescope have shown, Cygnus-X has a size of 200 parsecs and contains the largest number of massive protostars as well as the largest stellar association (Cygnus OB2, with up to 2,600 stars of spectral type OB and a mass of up to 105 solar masses) within a radius of 2 kiloparsecs of the Sun. It is also associated with one of the largest molecular clouds known, with a mass of 3 million solar masses. Its stellar population includes a large number of early-type stars as well as evolved massive stars such as luminous blue variable candidates, Wolf–Rayet stars, and supergiant stars of spectral types O and B.
Ongoing research has shown Cygnus X includes two stellar associations: Cygnus OB2 and Cygnus OB9 as well as an additional large number of early-type stars that include BD+40°4210, a blue supergiant star and luminous blue variable candidate that is one of the brightest stars of the association, as well as more supergiant stars of spectral types O and B. The same study shows that star formation has been taking place there during at least 10 million years, continuing to the present day.


Kepler-277c

Kepler-277c (also known by its Kepler Objects of Interest designation KOI-1215.02) is the third most massive and second-largest rocky planet ever discovered, with a mass about 64 times that of Earth. Discovered in 2014 by the Kepler Space Telescope, Kepler-277c is a Neptune-sized exoplanet with a very high mass and density for an object of its radius, suggesting a composition made mainly of rock with some amounts of water. Along with its sister planet, Kepler-277b, the planet's mass was determined using transit-timing variations (TTVs).
Characteristics.
Size and temperature.
Kepler-277c was detected using the transit method and TTVs, allowing for both its mass and radius to be determined to some level. It is approximately 3.36 , close to the size of Neptune. At that radius, most planets should be gaseous Mini-Neptunes with no solid surface. However, the mass of Kepler-277c is extremely high for its size. Transit-timing variations indicate a planetary mass of about 64.2 , close to Saturn's mass at 95.16 . The planet has a density of approximately 9.33 g/cm3 and about 5.7 times the surface gravity of Earth. Such a high density for an object of this size implies that, like its sister planet, Kepler-277c is an enormous rock-based planet with a small portion of its mass as water. It is currently the third most massive and second largest terrestrial planet ever discovered, behind Kepler-277b in mass and PSR J1719-1438 b in both radius and mass. Due to its proximity to its host star, Kepler-277c is quite hot with an equilibrium temperature of about , hot enough to melt certain metals.
Orbit.
Kepler-277c orbits close to its host star, with one orbit lasting 33.006 days. Its semi-major axis, or average distance from the parent object, is about 0.209 AU. For comparison, the planet Mercury in our Solar System takes 88 days to orbit at a distance of 0.38 AU. At this distance, Kepler-277c is very hot and most likely tidally locked to its host star. It is close to a 2:1 resonance with Kepler-277b.
Host star.
The parent star Kepler-277 is a large yellow star. It is 1.69 and 1.12 , with a temperature of 5946 K, a metallicity of -0.315 [Fe/H], and an unknown age. For comparison, the Sun has a temperature of 5778 K, a metallicity of 0.00 [Fe/H], and an age of about 4.5 billion years. The large radius in comparison to its mass and temperature suggest that Kepler-277 could be a Subgiant star.


NGC 4746

NGC 4746 is an edge-on spiral galaxy located 107 million light-years away in the constellation Virgo. It was discovered by John Herschel during a sky-survey on March 29, 1830.


R Puppis

R Puppis (R Pup) is a variable star in the constellation Puppis. It is a rare yellow hypergiant and a candidate member of the open cluster NGC 2439. It is also an MK spectral standard for the class G2 0-Ia.
Variability.
R Puppis was identified as a variable star in 1879, and described as having a range of over a magnitude. Numerous observations over the following 100 years failed to confirm the variations, until the 1970s when clear brightness changes were observed. These were confirmed by later observations, but with a total visual amplitude of only about 0.2 magnitudes.
Variable stars such as R Puppis have been described as pseudo-Cepheids, because they lie above the high-luminosity portion of the instability strip and their variations are similar to those of Cepheids although less regular. R Puppis is formally classified as a semiregular variable of type SRd, meaning F, G, or K giants or supergiants.