the Sun. One is around five times as luminous as the Sun and the other around four times as luminous. The system is classified as a Beta Lyrae variable, the apparent magnitude varying from 8.83 to 9.72 over 0.66 days. XX Pyxidis is one of the more-studied members of a class of stars known as Delta Scuti variables—short period (six hours at most) pulsating stars that have been used as standard candles and as subjects to study astroseismology. Astronomers made more sense of its pulsations when it became clear that it is also a binary star system. The main star is a white main sequence star of spectral type A4V that is around 1.85 ± 0.05 times as massive as the Sun. Its companion is most likely a red dwarf of spectral type M3V, around 0.3 times as massive as the Sun. The two are very close—possibly only 3 times the diameter of the Sun between them—and orbit each other every 1.15 days. The brighter star is deformed into an egg shape. AK Pyxidis is a red giant of spectral type M5III and semi-regular variable that varies between magnitudes 6.09 and 6.51. Its pulsations take place over multiple periods simultaneously of 55.5, 57.9, 86.7, 162.9 and 232.6 days. UZ Pyxidis is another semi-regular variable red giant, this time a carbon star, that is around 3560 times as luminous as the Sun with a surface temperature of 3482 K, located 2116 light-years away from Earth. It varies between magnitudes 6.99 and 7.83 over 159 days. VY Pyxidis is a BL Herculis variable (type II Cepheid), ranging between apparent magnitudes 7.13 and 7.40 over a period of 1.24 days. Located around 650 light-years distant, it shines with a luminosity approximately 45 times that of the Sun. The closest star to Earth in the constellation is Gliese 318, a white dwarf of spectral class DA5 and magnitude 11.85. Its distance has been calculated to be 26 light-years, or 28.7 ± 0.5 light-years distant from Earth. It has around 45% of the Sun's mass, yet only 0.15% of its luminosity. WISEPC J083641.12-185947.2 is a brown dwarf of spectral type T8p located around 72 light-years from Earth. Discovered by infrared astronomy in 2011, it has a magnitude of 18.79. Planetary systems Pyxis is home to three stars with confirmed planetary systems—all discovered by Doppler spectroscopy. A hot Jupiter, HD 73256 b, that orbits HD 73256