Pitch space

In music theory, pitch spaces model relationships between pitches. These models typically use distance to model the degree of relatedness, with closely related pitches placed near one another, and less closely related pitches placed farther apart. Depending on the complexity of the relationships under consideration, the models may be multidimensional. Models of pitch space are often graphs, groups, lattices, or geometrical figures such as helixes. Pitch spaces distinguish octave-related pitches. When octave-related pitches are not distinguished, we have instead pitch class spaces, which represent relationships between pitch classes. (Some of these models are discussed in the entry on modulatory space, though readers should be advised that the term "modulatory space" is not a standard music-theoretical term.) Chordal spaces model relationships between chords.
Linear and helical pitch space.
The simplest pitch space model is the real line. A fundamental frequency "f" is mapped to a real number "p" according to the equation
This creates a linear space in which octaves have size 12, semitones (the distance between adjacent keys on the piano keyboard) have size 1, and middle C is assigned the number 60, as it is in MIDI. 440 Hz is the standard frequency of 'concert A', which is the note 9 semitones above 'middle C'. Distance in this space corresponds to physical distance on keyboard instruments, orthographical distance in Western musical notation, and psychological distance as measured in psychological experiments and conceived by musicians. The system is flexible enough to include "microtones" not found on standard piano keyboards. For example, the pitch halfway between C (60) and C# (61) can be labeled 60.5.
One problem with linear pitch space is that it does not model the special relationship between octave-related pitches, or pitches sharing the same pitch class. This has led theorists such as M. W. Drobish (1855) and Roger Shepard (1982) to model pitch relations using a helix. In these models, linear pitch space is wrapped around a cylinder so that all octave-related pitches lie along a single line. Care must be taken when interpreting these models however, as it is not clear how to interpret "distance" in the three-dimensional space containing the helix; nor is it clear how to interpret points in the three-dimensional space not contained on the helix itself.
Higher-dimensional pitch spaces.
Other theorists, such as Leonhard Euler (1739), Hermann von Helmholtz (1863/1885), Arthur von Oettingen (1866), Hugo Riemann (who should not be confused with mathematician Bernhard Riemann), and Christopher Longuet-Higgins (1978) have modeled pitch relationships using two-dimensional (or higher-dimensional) lattices, under the name of Tonnetz. In these models, one dimension typically corresponds to acoustically-pure perfect fifths while the other corresponds to major thirds. (Variations are possible in which one axis corresponds to acoustically pure minor thirds.) Additional dimensions can be used to represent additional intervals including—most typically—the octave.
All of these models attempt to capture the fact that intervals separated by acoustically pure intervals such as octaves, perfect fifths, and major thirds are thought to be perceptually closely related. However, proximity in these spaces need not represent physical proximity on musical instruments: by moving one's hands a very short distance on a violin string, one can move arbitrarily far in these multiple-dimensional models. For this reason, it is hard to assess the psychological relevance of distance as measured by these lattices.
History of pitch space.
The idea of pitch space goes back at least as far as the ancient Greek music theorists known as the Harmonists. To quote one of their number, Bacchius,
"And what is a diagram? A representation of a musical system. And we use a diagram so that, for students of the subject, matters which are hard to grasp with the hearing may appear before their eyes." (Bacchius, in Franklin, "Diatonic Music in Ancient Greece".) The Harmonists drew geometrical pictures so that the intervals of various scales could be compared visually; they thereby located the intervals in a pitch space.
Higher-dimensional pitch spaces have also long been investigated. The use of a lattice was proposed by Euler (1739) to model just intonation using an axis of perfect fifths and another of major thirds. Similar models were the subject of intense investigation in the nineteenth century, chiefly by theorists such as Oettingen and Riemann (Cohn 1997). Contemporary theorists such as James Tenney (1983) and W.A. Mathieu (1997) carry on this tradition.
M.W. Drobisch (1855) was the first to suggest a helix (i.e. the spiral of fifths) to represent octave equivalence and recurrence (Lerdahl, 2001), and hence to give a model of pitch space. Shepard (1982) regularizes Drobish's helix, and extends it to a double helix of two wholetone scales over a circle of fifths which he calls the "melodic map" (Lerdahl, 2001). Michael Tenzer suggests its use for Balinese gamelan music since the octaves are not 2:1 and thus there is even less octave equivalence than in western tonal music (Tenzer, 2000). See also chromatic circle.
Instrument design.
Since the 19th century there have been many attempts to design isomorphic keyboards based on pitch spaces. The only ones to have caught on so far are several accordion layouts.


Victor Schumann

Victor Schumann (21 December 1841 – 1 September 1913) was a physicist and spectroscopist who in 1893 discovered the vacuum ultraviolet.
Schumann wished to study the "Extreme Ultraviolet" region. For this, he used a prism and lenses in fluorite instead of quartz allowing himself to be the first to measure spectra below 200 nm. Oxygen gas would absorb the radiation with a wavelength below 195 nm but Schumann placed the entire apparatus under vacuum. He prepared his own photographic plates with a reduced layer of gelatin.
He published on the Hydrogen line in the spectrum of Nova Aurigae and in the spectrum of vacuum tubes.
His work opened the way to atomic emission spectroscopy, leading eventually to the discovery of the hydrogen spectral lines series (Lyman series) by Theodore Lyman in 1914.


6230 Fram


929 Algunde

929 Algunde ("prov. designation:" "or" ), is a stony Flora asteroid from the inner regions of the asteroid belt, that measures approximately in diameter. It was discovered by German astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory on 10 March 1920. The S-type asteroid has a short rotation period of 3.3 hours and is likely spherical in shape. It was named "Algunde", a common German female name unrelated to the discoverer's contemporaries, that was taken from the almanac "Lahrer Hinkender Bote".
Orbit and classification.
When applying the synthetic hierarchical clustering method (HCM) by Nesvorný, or the 1995 HCM-analysis by Zappalà, "Algunde" is a member of the Flora family (), a giant asteroid family and the largest family of stony asteroids in the main-belt. However, according to another HCM-analysis by Milani and Knežević (AstDys), it is a background asteroid as this analysis does not recognize the Flora asteroid clan. "Algunde" orbits the Sun in the inner asteroid belt at a distance of 2.0–2.5 AU once every 3 years and 4 months (1,224 days; semi-major axis of 2.24 AU). Its orbit has an eccentricity of 0.11 and an inclination of 4° with respect to the ecliptic. The body's observation arc begins at Heidelberg Observatory on 12 March 1920, two nights after its official discovery observation.
Naming.
This minor planet was named "Algunde", after a female name picked from the "Lahrer Hinkender Bote", published in Lahr, southern Germany. A "Hinkender Bote" (lit. "limping messenger") was a very popular almanac, especially in the alemannic-speaking region from the late 17th throughout the early 20th century. The calendar section contains feast days, the dates of important fairs and astronomical ephemerides. For 30 January, the calendar gives "Algunde" as the German name day analogue next to "Adelgunde" and "Martina", the protestant and catholic entries in the calendar of saints, likely referring to Saint Aldegonde and Martina of Rome.
Reinmuth's "calendar names".
As with 22 other asteroids – starting with 913 Otila, and ending with 1144 Oda – Reinmuth selected names from this calendar due to his many asteroid discoveries that he had trouble thinking of proper names. These names are not related to the discoverer's contemporaries. Lutz Schmadel, the author of the "Dictionary of Minor Planet Names" learned about Reinmuth's source of inspiration from private communications with Dutch astronomer Ingrid van Houten-Groeneveld, who worked as a young astronomer at Heidelberg.
Physical characteristics.
In the Tholen classification, "Algunde" is a common stony S-type asteroid. It is also an S-type in the Bus–DeMeo taxonomy and in the Tholen-like taxonomy of the Small Solar System Objects Spectroscopic Survey (S3OS2). Only in the SMASS-like taxonomy of the S3OS2, "Algunde" is an Sl-subtype asteroid that transitions between the S-type and the uncommon L-type.
Rotation period.
In March 2007, a rotational lightcurve of "Algunde" was obtained from photometric observations by Slovak astronomers Adrián Galád and Leonard Kornoš at Modra Observatory . Lightcurve analysis gave a well-defined rotation period of hours with a low brightness amplitude of magnitude, indicative of a spherical rather than elongated shape (). Between 2008 and 2018, numerous follow-up observations by other astronomers confirmed the period of 3.31 hours with brightness variation maxima between 0.11 and 0.17.
Diameter and albedo.
According to the survey carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer (WISE), "Algunde" measures () and () kilometers in diameter and its surface has an albedo of () and (), respectively. The "Collaborative Asteroid Lightcurve Link" takes Petr Pravec's revised WISE data with an albedo of 0.2055 and a diameter of 12.45 kilometers based on an absolute magnitude of 11.86. Another publication by the WISE team gives a mean-diameter of () kilometers and an albedo of ().


Jill Dever

Jill A. Dever is an American statistician specializing in survey methodology who works as a senior researcher and senior director in the division for statistical & data sciences at RTI International.
Education.
Dever is a graduate of the University of Louisville. Majoring in mathematics there, she was encouraged by a faculty member, Steven Seif, to continue in statistics. She earned a master's degree in biostatistics from the University of North Carolina at Chapel Hill, and completed her Ph.D. in survey methodology at the University of Maryland, College Park. Her 2008 dissertation, "Sampling Weight Calibration with Estimated Control Totals", was supervised by Richard Valliant.
Book.
With Richard Valliant and Frauke Kreuter, Dever is a co-author of the book "Practical Tools for Designing and Weighting Survey Samples" (Springer, Statistics for Social and Behavioral Sciences, 2013; 2nd ed., 2018).
Recognition.
In 2015 Dever was elected as a Fellow of the American Statistical Association.


Primary School Leaving Examination

The Primary School Leaving Examination (PSLE) is a national examination in Singapore that is administered by the Ministry of Education and taken by all students near the end of their sixth year in primary school before they move on to secondary school. The examination test students' proficiency in the English language, their respective mother tongue languages (typically Chinese, Malay or Tamil), mathematics and science. Students have around two hours to complete each subject paper except for certain components of language subjects. Students answering multiple choice questions by shading their responses on a standardised optical answer sheet (OAS) that uses optical mark recognition to detect answers or by writing their workings and/or answers on the question booklet itself for certain sections of the paper.
The format of the PSLE and the presence of it in the Singapore education system gives it a part of its national culture. PSLE material has also been exported to some schools in other countries, particularly in Southeast Asia, China, India and Japan, having their students sit the international version of the exam, the iPSLE, to provide a benchmark of their performance by comparing to Singapore's educational standards.
In March 2018, calls for the removal of the PSLE was rejected in parliament by then Education Minister (Schools) Ng Chee Meng, he cited it as a "useful checkpoint" in a child's education journey. On 28 September 2018, Education Minister Ong Ye Kung reiterated his stance on keeping the
PSLE while announcing that the ministry will remove several mid-year and year-end exams across the board from primary one up to secondary four with the aim of reducing assessments based on exam results and to encourage students to be an all rounder.
History and past performance.
The Primary School Leaving Examination (PSLE) was modeled after the British Eleven plus exam (11+) and was first conducted in 1960. Its predecessor was the Secondary School Entrance Examination (SSEE), which was conceived in 1952 when it was known as the Standard Six Entrance Examination up to 1954 and then as Secondary School Entrance Examination when the primary school classes were no longer named as Primary 1 & 2 and the standard 1 to 5 and started from Primary 1 to 6 instead. Promotion was to Form 2 in the secondary school instead of the previous Standard Six starting from January 1955, during the early days of self-government.
Though complaints were made about the 2007 PSLE Papers being out of syllabus and too challenging, this continued in the 2008 PSLE Paper. The difficult questions in the papers were intended to filter the higher average and lower average students, as explained by the Singapore Ministry of Education.
In 2009, such things happened again, with plenty of students unable to finish the maths paper. The entry scores for schools in 2009 dropped for many schools. For example, Hwa Chong Institution and National Junior College saw their PSLE cut-off point drop by two T-score marks.
Performance.
In 2005, 51 087 pupils sat for the examination, a 0.4% increase from the previous year. The majority (or roughly 97.8%) of the pupils qualified for secondary school. 62.2% of those who passed were eligible for the Special (Integrated Programme or The International Baccalaureate) or the Express stream (Either one for 4 years only) and the remaining 35.6% were eligible for either the Normal (Academic) or Normal (Technical) courses (Either one for 5 years). 1163 pupils (2.3%) of the cohort assessed were not ready for secondary school in 2006 or were more suited for vocational training.
39,286 students sat for the PSLE in 2015. The Ministry of Education (MOE) said that a total of 38,610 students (98.3 %) were eligible for secondary school. 66.2 % of the pupils qualified for the Express stream, 21.7 % for Normal (Academic), and 10.4 % qualified for Normal (Technical). The other 1.7 % had dropped out and did not continue on to secondary school.
Controversy on flaws in papers.
The 2005 mathematics paper for EM1 and EM2 students was flawed due to a question having no definite method of working the answer out. The "Question 13" was spotted by many and became infamous. The question was mathematically inconsistent in that one will get one set of answers when worked out one way and another set of answers when worked out by a different method. The Singapore Examinations and Assessment Board (SEAB) acknowledged the mistake a few days after the examination, annulling the question and awarding 2 marks to every student for the question.
Controversy on withholding of result slips.
In 2019, public debate arose concerning the practice of withholding PSLE result slips from students for failing to pay school fees. This ensued after news claiming that a student was withheld her PSLE result slip, due to being unable to pay school fees, circulated widely on social media. Subsequently, then Education Minister Ong Ye Kung asked for the Ministry of Education to re-evaluate the practice of withholding PSLE result slips from students due to unpaid school fees.
Other methods of admission to secondary schools.
Students have the choice to go to other schools which do not use the posting system. Some of the top schools and the government schools have Direct School Admission (DSA). Some can go to other schools such as Singapore Sports School, NUS High School of Mathematics and Science or School of the Arts and School of Science and Technology.
Direct School Admission.
Independent schools and Autonomous schools can admit up to 20% and 10% of their students via the Direct School Admission scheme (DSA) respectively. Students apply through exercises conducted by the schools around July and August, receiving notice of the results shortly after. Schools offering the Integrated Programme (IP) can take in as many students as they want via DSA. Other schools have also been granted permission by the Ministry of Education to take in students specialising in the schools' niche areas up to a maximum of 5% of their total student intake.
International schools.
Since 2004, two international schools were given licenses to operate under the Ministry of Education's compulsory practices such as playing the national anthem, and following the nation's bilingual policies, to allow Singaporean or Singapore Permanent Resident students to enter without the Ministry of Education's permission. These schools were granted the permission in April 2004 and started the school year in January 2005. They are Anglo-Chinese School (International) and Hwa Chong International School. Another school was granted the permission to set up a school similar to the original two in 2006, the school is Saint Joseph's International School, which offers a similar programme to ACS (International).
Singapore Sports School.
The Singapore Sports School is for students who are perceived by the school to excel in sports it offers. This includes swimming, badminton, table tennis, soccer, golf, track and field, netball and sailing. It was opened in January 2004 and the school takes students directly into the school provided they have an active background in the sports offered by the school. When the school had its first intake, many students applied who were judged to excel in their sport but were posted to the Normal (Academic) or Normal (Technical) streams. The school rejected these pupils as the school sought pupils who excelled both physically and academically. The school was criticised for being too result wise instead of grooming them into future sportspeople. Some of the students were finally accepted on an appeal basis after that. Students in the school aim for the International Baccalaureate (IB) paper, similar to the Singapore School Of the Arts.
NUS High School.
The NUS High School of Mathematics and Science opened in 2005 with an intake of 225 Secondary 1 and 3 students, offering a six-year programme leading to the NUS High Diploma. Students will also sit for Advanced Placement (AP) and Scholastic Assessment Test (SAT) examinations in the senior years for benchmarks for admission into foreign universities. The school offers an accelerated mathematics and science curriculum based on a modular system, also offering languages, humanities, arts, and other elective subjects integrated into its modular system. Students are admitted based on several factors, performance in an application form, interviews, tests, and an admission camp.
School of Science and Technology, Singapore.
The School of Science and Technology (SST) is located at Technology Drive, which is about seven minutes walk from Dover MRT station. There is also a bus stop outside the school campus.


HD 4308

HD 4308 is a single star in the southern constellation of Tucana. It has a yellow hue and is a challenge to view with the naked eye even under good seeing conditions, having an apparent visual magnitude of 6.54. This object is located at a distance of 72 light years, as determined from parallax measurements. It is a population II star and is considered to be a member of the thick disk. The star is receding from the Sun with a radial velocity of +95 km/s.
This is a Sun-like G-type main-sequence star with a stellar classification of G6VFe-0.9, where the suffix notation indicates an underabundance of iron in the spectrum. The age of the star is poorly constrained, with estimated ranging from 1.6 billion years up to 10 billion. It has 95% of the mass of the Sun but 104% of the Sun's radius. The star is radiating nearly the same luminosity as the Sun from its photosphere at an effective temperature of 5,714 K.
Planetary system.
In 2005, a low-mass planet was found in orbit around this star using the radial velocity method with the HARPS spectrograph. It is following a circular orbit close to its host star with a period of just 15.6 days. Unusual for a star with planets, HD 4308 has a metallicity lower than that of the Sun.


R v Kang-Brown

R v Kang-Brown, , is a constitutional decision by the Supreme Court of Canada on the limits of police powers for search and seizure. The Court found that police do not have the right to perform a sniffer-dog search (to use dogs to conduct random searches) of public spaces when such search is not specifically authorized by statute. In this case, a suspect's section 8 rights under the "Canadian Charter of Rights and Freedoms" ("Charter") were violated when a police officer stopped him at a bus station and sniffer-dog searched his bag finding drugs in his possession.
Background.
On January 25, 2002, at about 11:00 a.m. at the Calgary, Alberta, bus terminal, three police officers were involved in a special operation designed to detect drug couriers. While observing a bus arriving at the station, they spotted the accused, Gurmakh Kang-Brown, disembarking from the all-night Greyhound bus from Vancouver. The accused gave the officers an elongated stare. The officers found the accused's behaviour suspicious, stopped him and asked him if he was carrying narcotics. The accused said no. Then, one of the officers asked to look in the accused's bag. The accused put his bag down and unzipped it. When the accused was unzipping the bag, the officer went to touch the bag. The accused pulled it away, looking nervous. The officer signaled another officer to have a drug-sniffing dog sniff the man's bag. The dog indicated the presence of drugs in the bag.
The officers arrested the accused for possession of and/or trafficking in drugs, searched him and found drugs on his person and in his bag.
Lower court rulings.
Trial Court.
At trial, the judge found that the accused was neither detained nor searched unlawfully and that the odours from the bag, which emanated freely in a public transportation facility, did not constitute information in which the accused had a reasonable expectation of privacy. Accordingly, section 8 of the "Charter" was not implicated.
Court of Appeal.
On appeal, the Alberta Court of Appeal agreed with the trial judge that there had been no detention and that the question was whether the ordinary citizen who has committed no offence has a reasonable expectation of privacy which would be significantly invaded by the police action in question. To determine whether the accused had a reasonable expectation of privacy, the following factors were considered:
The Court concluded that there was no reasonable expectation of privacy for that limited information in that public place and that there was no search. He agreed with the trial judge that even if there had been a "Charter breach", the evidence ought not to be excluded under section 24(2) of the "Charter".
Supreme Court ruling.
The accused appealed to the Supreme Court. The Court found that the search and detention violated section 8 of the "Charter" and that the evidence should be excluded because it would interfere with the fairness of justice under section 24(2) of the "Charter". Hence, the conviction was set aside.
The following issues were put to the Court:
Opinion of the Court.
All the nine judges agreed that the dog sniff of the passenger's bag at the bus station amounted to a search within section 8 of the "Charter".
McLachlin CJ and Binnie, LeBel, Fish, Abella and Charron JJ agreed that the sniffer dog search of the passenger’s bag at the bus station violated section 8 of the "Charter" and that in the circumstances of this case, the evidence should be excluded pursuant to section 24(2) of the "Charter".
According to LeBel, Fish, Abella and Charon JJ, the sniffer-dog search breached section 8 because such a search was not specifically authorized by statute. In determining whether the police were authorized at common law to conduct the search in fulfillment of their general duty to investigate crime, the threshold for the exercise of police powers should not be lowered to one of "reasonable suspicion", since to do so would impair the important safeguards found in section 8 against unjustified state intrusion. The existing and well established standard of "reasonable and probable grounds" should be applied. In this case, the search did not meet this standard.
According to McLachlin CJ and Binnie J, a proper balance between an individual's section 8 rights and the reasonable demands of law enforcement would be struck by permitting such "sniff" searches on a "reasonable suspicion" standard without requiring prior judicial authorization.
Reasonable suspicion standard.
"Suspicion" is an expectation that the targeted individual is possibly engaged in some criminal activity. A "reasonable" suspicion means something more than a mere suspicion and something less than a belief based upon reasonable and probable grounds. Because sniffer dog searches are conducted without prior judicial authorization, the after the fact judicial scrutiny of the grounds for the alleged "reasonable suspicion" must be rigorous. Here, the police action was based on speculation. The sniff in this case was an unreasonable search since the RCMP officer did not have grounds for reasonable suspicion at the time the dog was called. However, because of R. v. MacKenzie, [2013] 3 SCR 250, 2013 SCC 50 (CanLII), police can now simply draw on their experience in the field to create broad categories of “suspicious” behaviour into which almost anyone could fall. Such an approach risks transforming the already flexible standard of reasonable suspicion into the “generalized” suspicion standard.
Dissent.
Bastarache, Deschamps and Rothstein JJ dissented. They found that the dog sniff of the passenger's bag at the bus station amounted to a search under section 8 of the "Charter". However, there is no need to determine whether the evidence should be excluded pursuant to section 24(2) of the "Charter" because the sniffer dog search of the passenger’s bag at the bus station did not violate section 8 of the "Charter".


3775 Ellenbeth


2074 Shoemaker

2074 Shoemaker, provisional designation , is a stony Hungaria asteroid, Mars-crosser and suspected synchronous binary system from the innermost regions of the asteroid belt, approximately 4 kilometers in diameter. It was discovered on 17 October 1974, by astronomer Eleanor Helin at the Palomar Observatory. She named it after American astronomer Eugene Shoemaker.
Orbit and classification.
"Shoemaker" is a bright member of the dynamical Hungaria group that forms the innermost dense concentration of asteroids in the Solar System. It orbits the Sun in the inner main-belt at a distance of 1.7–1.9 AU once every 2 years and 5 months (882 days). Its orbit has an eccentricity of 0.08 and an inclination of 30° with respect to the ecliptic. With a perihelion of 1.6521 AU, "Shoemaker" is a Mars-crossing asteroid as it crosses the orbit of Mars at 1.666 AU.
The body's observation arc begins with a precovery taken at Palomar in April 1954, more than 20 years prior to its official discovery observation.
Physical characteristics.
In the SMASS classification, "Shoemaker" is a Sa-subtype, that transitions form the common stony S-type asteroids to the A-type asteroids.
Rotation period.
Several rotational lightcurve of "Shoemaker" were obtained from photometric observations by American astronomer Brian Warner at his Palmer Divide Observatory () and CS3-Station (). Analysis of the best-rated lightcurves gave a well-defined rotation period of 2.5328 hours with a brightness amplitude of 0.13 magnitude ().
Suspected binary.
In October 2003, photometric observations of "Shoemaker" by Robert D. Stephens gave a long rotation period of 57.02 hours. After re-measuring the images with newer software and calibration techniques, two mutual occultation and eclipsing events were found, indicating that "Shoemaker" might be a synchronous binary asteroid with a minor-planet moon orbiting it every 55 hours. Observations in 2010, were difficult due to incomplete coverage and gave an orbital period of 27.39 hours for the secondary. Observations by astronomers at Etscorn Campus Observatory () in 2015, did not mention any mutual events.
In June 2017, Warner measured a rotation period of hours and an orbital period for the secondary of 44.28 hours at his CS3-Palmer Divide Station in California. The binary nature of "Shoemaker" remains unconfirmed.
Diameter and albedo.
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, "Shoemaker" measures 3.18 and 3.22 kilometers in diameter and its surface has an albedo between 0.41 and 0.52, respectively. The "Collaborative Asteroid Lightcurve Link" assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 4.93 kilometers based on an absolute magnitude of 13.9.
Naming.
This minor planet was named by the discoverer after her colleague, the American astronomer Eugene Shoemaker (1928–1997), who was a discoverer of minor planets and of the Comet Shoemaker–Levy 9 that collided with Jupiter. He is well known for his work on impact craters and his role in the lunar Ranger, Surveyor and Apollo programs.
The naming was also proposed by Brian G. Marsden, the director of the Minor Planet Center (MPC). The official was published by the Minor Planet Center on 1 November 1978 ().


Ancient Roman units of measurement

The ancient Roman units of measurement were primarily founded on the Hellenic system, which in turn was influenced by the Egyptian system and the Mesopotamian system. The Roman units were comparatively consistent and well documented.
Length.
The basic unit of Roman linear measurement was the pes or Roman foot (plural: "pedes"). Investigation of its relation to the English foot goes back at least to 1647, when John Greaves published his "Discourse on the Romane foot". Greaves visited Rome in 1639, and measured, among other things, the foot measure on the tomb of Titus Statilius Aper, that on the statue of Cossutius formerly in the gardens of Angelo Colocci, the congius of Vespasian previously measured by Villalpandus, a number of brass measuring-rods found in the ruins of Rome, the paving-stones of the Pantheon and many other ancient Roman buildings, and the distance between the milestones on the Appian Way. He concluded that the Cossutian foot was the "true" Roman foot, and reported these values compared to the iron standard of the English foot in the Guildhall in London (30.4919cm):
Smith (1851) gives a value of 0.9708 English feet, or about 295.9 mm. An accepted modern value is 296 mm.
The Roman foot was sub-divided either like the Greek "pous" into 16 "digiti" or fingers; or into 12 "unciae" or inches. Frontinus writes in the 1st century AD that the "digitus" was used in Campania and most parts of Italy. The principal Roman units of length were:
Other units include the schoenus (from the Greek for "rush rope") used for the distances in Isidore of Charax's "Parthian Stations" (where it had a value around ) and in the name of the Nubian land of Triacontaschoenus between the First and Second Cataracts on the Nile (where it had a value closer to ).
Area.
The ordinary units of measurement of area were:
Other units of area described by Columella in his "De Re Rustica" include the "porca" of 180 × 30 Roman feet (about ) used in Hispania Baetica and the Gallic "candetum" or "cadetum" of 100 feet in the city or 150 in the country. Columella also gives uncial divisions of the "jugerum", tabulated by the anonymous translator of the 1745 Millar edition as follows:
Volume.
Both liquid and dry volume measurements were based on the sextarius. The sextarius was defined as of a cubic foot, known as an amphora quadrantal. Using the value for the Roman foot, an amphora quadrantal can be computed at approximately , so a sextarius (by the same method) would theoretically measure , which is about 95% of an imperial pint (568.26125 ml).
Archaeologically, however, the evidence is not as precise. No two surviving vessels measure an identical volume, and scholarly opinion on the actual volume ranges between and .
The core volume units are:
Weight.
The units of weight or mass were mostly based on factors of 12. Several of the unit names were also the names of coins during the Roman Republic and had the same fractional value of a larger base unit: libra for weight and as for coin. Modern estimates of the libra range from with 5076 grains or an accepted figure. The "as" was reduced from 12 ounces to 2 after the First Punic War, to 1 during the Second Punic War, and to half an ounce by the 191 BC Lex Papiria.
The divisions of the libra were:
The subdivisions of the uncia were:
Unicode.
A number of special symbols for Roman currency were added to the Unicode Standard version 5.1 (April 2008) as the Ancient Symbols block (U+10190–U+101CF, in the Supplementary Multilingual Plane ).
As mentioned above, the names for divisions of an as coin (originally one libra of bronze) were also used for divisions of a libra, and the symbols U+10190–U+10195 are likewise also symbols for weights:
Time.
Years.
The complicated Roman calendar was replaced by the Julian calendar in 45 BC. In the Julian calendar, an ordinary year is 365 days long, and a leap year is 366 days long. Between 45 BC and AD 1, leap years occurred at irregular intervals. Starting in AD 4, leap years occurred regularly every four years. Year numbers were rarely used; rather, the year was specified by naming the Roman consuls for that year. (As consuls' terms latterly ran from January to December, this eventually caused January, rather than March, to be considered the start of the year.) When a year number was required, the Greek Olympiads were used, or the count of years since the founding of Rome, "ab urbe condita" in 753 BC. In the middle ages, the year numbering was changed to the Anno Domini count.
The calendar used in most of the modern world, the Gregorian calendar, differs from the Julian calendar in that it skips three leap years every four centuries to more closely approximate the length of the tropical year.
Weeks.
The Romans grouped days into an eight-day cycle called a "nundina", with every eighth day being a market day.
Independent of the "nundinae", astrologers kept a seven-day cycle called a "hebdomada" where each day corresponded to one of the seven classical planets, with the first day of the week being Saturn-day, followed by Sun-day, Moon-day, Mars-day, Mercury-day, Jupiter-day, and lastly Venus-day. Each astrological day was reckoned to begin at sunrise. The Jews also use a seven-day week, which began Saturday evening. The seventh day of the week they called Sabbath; the other days they numbered rather than named, except for Friday, which could be called either the Parasceve or the sixth day. Each Jewish day begins at sunset. Christians followed the Jewish seven-day week, except that they commonly called the first day of the week the "Dominica", or the Lord's day. In 321 Constantine the Great gave his subjects every Sunday off in honor of his family's tutelary deity, the Unconquered Sun, thus cementing the seven-day week into Roman civil society.
Hours.
The Romans divided the daytime into twelve "horae" or hours starting at sunrise and ending at sunset. The night was divided into four watches. The duration of these hours varied with seasons; in the winter, when the daylight period was shorter, its 12 hours were correspondingly shorter and its four watches were correspondingly longer.
Astrologers divided the solar day into 24 equal hours, and these astrological hours became the basis for medieval clocks and our modern 24-hour mean solar day.
Although the division of hours into minutes and seconds did not occur until the middle ages, ancient astrologers had a "minuta" equal to of a day (24 modern minutes), a "secunda" equal to of a day (24 modern seconds), and a "tertia" equal to of a day (0.4 modern seconds).


Grrr Records

Grrr Records is a French avant-garde jazz record label founded by Jean-Jacques Birgé in 1975.
The first LP was "Défense de" by Birgé-Gorgé-Shiroc which became a cult-album after having been quoted in the Nurse with Wound list. Grrr has been issuing CDs since 1987 with "L'hallali" by Un Drame Musical Instantané, led by multi-instrumentalist Jean-Jacques Birgé, trumpeter Bernard Vitet and guitarist Francis Gorgé, main group of the label which also produced the albums of multi-instrumentalist composer Hélène Sage, accordionist Michèle Buirette and female trio Pied de Poule (M. Buirette, bassist, Geneviève Cabannes, and singer Dominique Fonfrède). Barcelonian label Wah Wah has reissued "Défende de" and Austrian label Klang Galerie issues remastered CDs of all LPs by Un drame musical instantané.
In 1997, "Carton" by Birgé-Vitet (with Michel Séméniako's photographs) is their first enhanced-CD and Birgé's first multimedia artwork as an author. It will be followed by "Machiavel" by Un d.m.i. (CD-audio + CD-ROM), with an interactive video sessions of 111 loops by J-J. Birgé and Antoine Schmitt. Last albums produced by Grrr, are "Établissement d'un ciel d'alternance", duet with Birgé and famous French writer Michel Houellebecq who reads his own text (No. 26), "Échappée belle" by Hélène Sage (No. 27), 2 albums by Michèle Buirette and, in 2017, "Long Time No Sea" by trio El Strøm (N°29) and in 2018, The "100th Anniversary of Jean-Jacques Birgé" (N°30)! In 2020, for the double CD "Pique-nique au labo" (N°31-32), Birgé invites 28 famous improvisers to join him for friendly meetings which cover the period 2010-2019.
Since 2011 Grrr has issued freely downloadable material (84 unissued albums + a random radio which feature 1104 pieces and last 166 hours).
Grrr belongs to Les Allumés du Jazz, 90 French independent jazz and improvised music labels.
See also.
List of record labels


Seychellois units of measurement

Several units of measurement were used in Seychelles to measure quantities like, for example, capacity. The metric system has been compulsory in Seychelles (and adopted since 1880). Before metric adoption, old French, British and some additional units were used.
System before metric system.
Units from old French and British systems, were used before metrication.
Capacity.
In addition to old French and British units, following units were used:
1 cash = 227.11 l
1 velt = cash.


4205 David Hughes

4205 David Hughes, provisional designation , is a Mars-crossing asteroid from inside the innermost regions of the asteroid belt, approximately in diameter. It was discovered on 18 December 1985, by American astronomer Edward Bowell at Lowell's Anderson Mesa Station near Flagstaff, Arizona. The transitional X-type asteroid has a longer-than average rotation period of at least 24 hours. It was named for British astronomer David Hughes.
Orbit and classification.
"David Hughes" is a Mars-crossing asteroid, a member of the dynamically unstable group, located between the main belt and near-Earth populations, and crossing the orbit of Mars at 1.666 AU. It orbits the Sun inside the innermost region of the asteroid belt at a distance of 1.5–2.0 AU once every 2 years and 3 months (829 days; semi-major axis of 1.73 AU). Its orbit has an eccentricity of 0.15 and an inclination of 16° with respect to the ecliptic. On 12 October 2026 it will pass from Mars. Another close Martian approach will occur at a similar distance on 24 November 2103.
The body's observation arc begins with a precovery taken at the Siding Spring Observatory in June 1980, or five years prior to its official discovery observation at Anderson Mesa.
Physical characteristics.
In the SMASS classification, "David Hughes" is a Xe-subtype that transitions from the X-type to the very bright E-type asteroids.
Rotation period.
In August 2012, a rotational lightcurve of "David Hughes" was obtained from photometric observations by Italian amateur astronomers Roberto Crippa and Federico Manzini at the Sozzago Astronomical Station . Lightcurve analysis gave a rotation period of at least 24 hours with a brightness amplitude of 0.25 magnitude (). Most asteroids have a period shorter than 20 hours "(also see List of slow rotators)".
Diameter and albedo.
The "Collaborative Asteroid Lightcurve Link" assumes an albedo of 0.20 and calculates a diameter of 3.92 kilometers based on an absolute magnitude of 14.4.
This makes "David Hughes" one of the smallest mid-sized Mars-crossing asteroids smaller than 1065 Amundsenia (9.75 km), 1474 Beira (8.73 km), 1011 Laodamia (7.5 km), 1727 Mette (est. 9 km), 1131 Porzia (7.13 km), 1235 Schorria (est. 9 km), 985 Rosina (8.18 km), 1310 Villigera (15.24 km) and 1468 Zomba (7 km), and much smaller than the largest members of this dynamical group, namely, 132 Aethra, 323 Brucia, 1508 Kemi, 2204 Lyyli and 512 Taurinensis, which are all larger than 20 kilometers in diameter.
Naming.
This minor planet was named after British astronomer and professor of astronomy at the University of Sheffield. The official naming citation was published by the Minor Planet Center on 2 November 1990 ().


2280 Kunikov


Karatmeter

The Karatmeter is a scientific instrument which uses X-rays to give an exact reading of the purity of gold. Due to its very high precision and fast result, X-ray analysis has been adopted by international agencies in India as part of the certification process used to hallmark gold. It is an accurate, non-destructive means of testing the purity of gold and other related elements. X-Ray method of Gold analysis gives the purity of gold up to 10-12 microns and hence it gives the analysis of coating only.
Using this technique, the precise percentage or karat (of karat) in a solid piece of jewellery can be determined in 30 seconds. It also accurately determines the element composition of all types of gold, white gold, platinum, silver, palladium, rhodium and related alloys.
Energy dispersive X-Ray fluorescence (ED-XRF) is a simple, accurate and economic analytical methods for the determination of the chemical composition of many types of materials. It is non-destructive and reliable, requires very little sample preparation and is suitable for solid, liquid and powdered samples. It can be used for a wide range of elements, from Chlorine (17) to Uranium (92), and provides detection limits at the sub-ppm level.
There are many models of Gold Purity Testing machines available - from portable (light weight) to industrial grade machines.
Apart from X-ray spectrometer technique, other older traditional methods are using the TouchStone and Acid to test the gold purity. But TouchStone and Acid are destructive testing - a tiny sample of gold is cut and then tested. The sample is rubbed on TouchStone and a drop of acid is put on it and the goldsmith observes the residue using a magnifying lens. Based on experience, gold smith can determine purity of sample.


Conservation Canines

Conservation Canines (CK9) is a non-profit organization that trains detection dogs and their handlers for the purposes of wildlife research. It is part of the Center for Conservation Biology at the University of Washington. Since 1997, led by Dr. Samuel Wasser, Conservation Canines has worked internationally with species including the Pacific Pocket Mouse, the Jemez Mountains salamander, Killer whales, and Tigers.
The training facility is located in Eatonville, WA. Current and former client partners include The Nature Conservancy, U.S. Fish and Wildlife Service, U.S. Forest Service, as well as various universities and state and local agencies.
CK9 helped Western Ecological Research Center researchers survey conserved grasslands in San Diego County and found that indeed badgers are active.
Conservation Canines sources their dogs from shelters and rescue organizations. Dogs are trained using a ball or toy reward system.


958 Asplinda

958 Asplinda ("prov. designation": "or" ) is a resonant Hilda asteroid, approximately in diameter, located in the outermost region of the asteroid belt. It was discovered on 28 September 1921, by astronomer Karl Reinmuth at the Heidelberg Observatory in southwest Germany. The assumed C-type asteroid has a rotation period of 16.5 hours and is likely elongated in shape. It was named after Swedish astronomer Bror Asplind (1890–1954).
Orbit and classification.
"Asplinda" is a member of the distant orbital Hilda group of asteroids, which stay in a 3:2 orbital resonance with Jupiter. It is however not a member of the collisional Hilda family () but a non-family asteroid of the background population when applying the hierarchical clustering method to its proper orbital elements. It orbits the Sun in the outermost asteroid belt at a distance of 3.2–4.7 AU once every 7 years and 11 months (2,905 days; semi-major axis of 3.98 AU). Its orbit has an eccentricity of 0.18 and an inclination of 6° with respect to the ecliptic. The body's observation arc begins at Heidelberg on 24 October 1921, four weeks after its official discovery observation.
Naming.
This minor planet was named after Bror Ansgar Asplind (1890–1954), a Swedish astronomer and orbit computer. The following, sequentially numbered asteroids 959 Arne, 960 Birgit and 961 Gunnie are named after his three children, respectively. The was mentioned in "The Names of the Minor Planets" by Paul Herget in 1955 ().
Physical characteristics.
No spectral type has been published for "Asplinda". As an Hildian asteroid with a low albedo "(see below)" it is a carbonaceous C-type asteroid (assumed), or possibly a D-type or P-type asteroid, which are very common among the Hildian and more distant Jupiter trojan population.
Rotation period and poles.
In December 2017, a rotational lightcurve of "Asplinda" was obtained from photometric observations by Brian Warner, Robert Stephens and Daniel Coley at the Center for Solar System Studies in California. Lightcurve analysis gave a rotation period of hours with a high brightness amplitude of magnitude, indicative of an elongated, non-spherical shape (). The results supersedes previous observations with a period determination of by the same astronomers in 2016, and a period of published by Mats Dahlgren in 1998 ().
The 2017 observations by Warner, Stephens and Coley also gave two spin axes of (228.0°, 33.0°) and (46.0°, 45.0°) in ecliptic coordinates (λ, β) and a sidereal period of hours.
These results supersede the asteroid's 2016 modeled spin axes and lightcurve with a sidereal period of hours based on data from the Uppsala Asteroid Photometric Catalogue, the Palomar Transient Factory survey, and individual observers lead by Czech astronomers Josef Hanuš and Josef Ďurech, as well as sparse-in-time photometry from the NOFS, the Catalina Sky Survey, and the La Palma surveys .
Diameter and albedo.
According to the surveys carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer (WISE), the Infrared Astronomical Satellite IRAS, and the Japanese Akari satellite, "Asplinda" measures , and kilometers in diameter, and its surface has an albedo of , and , respectively.
Another published measurement by the WISE team also gives a mean-diameters of with corresponding albedo of . The "Collaborative Asteroid Lightcurve Link" adopts the results from IRAS, that is, an albedo of 0.0415 and a diameter of 47.08 km based on an absolute magnitude of 10.71. An asteroid occultation on 15 August 2006, gave a best-fit ellipse dimension of 47.0 × 47.0 kilometers. These timed observations are taken when the asteroid passes in front of a distant star. However the quality of the measurement is poorly rated.


Shure Beta 58A

The Shure Beta 58A is a rugged dynamic supercardioid microphone developed by Shure Incorporated specifically for live vocal performances. The microphone won a TEC Award in 1996 for outstanding microphone technology.
Shure's Beta series of microphones was introduced in 1989. Originally the Beta 58 was available as the Beta 58C (chrome grill) or the Beta 58M (matte grill). The Beta 58C was eventually discontinued and the Beta 58M became just the Beta 58. The Beta 58 was then discontinued and replaced by the Beta 58A.
Development.
In 1996, Shure altered the Beta 58 to create the Beta 58A, with a completely new cartridge design, meant to mimic the old cartridge as far as polar pattern, output level, and frequency response, but with slightly different sounds characteristics; the revised design also removed the hum-bucking coil and added an output transformer.
Comparisons.
Regarding the difference between the Beta 58 and Beta 58A, the manufacturer's website says, "The Beta 58A has a completely new cartridge in it. While the new cartridge is meant to mimic the old cartridge as far as polar pattern, output level, and frequency response goes, it is a different cartridge and will sound slightly different. Two major differences are that we removed the hum bucking coil on the new model and added an output transformer."
Though the shape and intended applications are similar, the Beta 58A has little in common with the earlier and popular SM58. The Beta series uses a capsule and a transformer different from the SM series.
Performance.
The Beta 58A has a frequency response extending from 50 to 16,000 Hz, with frequencies attenuated below 500 Hz to counter the proximity effect. The Beta 58A has two high frequency presence peaks, one at 4 kHz and another at 10 kHz.


4327 Ries


Margaret K. Butler

Margaret Kampschaefer Butler (March 27, 1924 – March 8, 2013) was a mathematician who participated in creating and updating computer software. During the early 1950s, Butler contributed to the development of early computers. Butler was the first female fellow at the American Nuclear Society and director of the National Energy Software Center at Argonne. Butler held leadership positions within multiple scientific organizations and women's groups. She was the creator and director of the National Energy Software Center. Here, Butler operated an exchange for the editing of computer programs in regards to nuclear power and developed early principles for computer technology.
Early life and education.
Butler was born on March 27, 1924 in Evansville, Indiana.
Career.
Butler began her career in 1944 working as a statistician at the Bureau of Labor Statistics. While she worked there, she also taught math at the United States Department of Agriculture Graduate School and took graduate courses related to sampling theory. About a year later, she joined the United States Army Air Forces and worked as a civilian in Germany. She returned to the United States after two years and began working in the Naval Reactors Division of Argonne National Laboratory as a junior mathematician. While working at Argonne, Butler made calculations for physicists creating a prototype for a submarine reactor and attended atomic physics and reactor design classes. In 1949, she worked at the Bureau of Labor Statistics in Minnesota but returned to Argonne National Laboratory in 1951. Following her return to Argonne, Butler became an assistant mathematician in the Reactor Engineering Division and worked on AVIDAC, an early computer. In the 1950s Butler wrote software, reactor applications, mathematical subroutines, and utilities for three other Argonne computers, the ORACLE, GEORGE, and UNIVAC. From the late 1950s to early 1960s she led Argonne's Applied Mathematics Division's Application Programming. While working in this department, Butler developed teams to fix program problems in reactors, biology, chemistry, physics, management, and high energy physics applications. In 1960, Butler worked with others to establish the Argonne Code Center, which later became the National Energy Software Center (NESC). Butler would later become director of the NESC from 1972–1991. In 1980, Butler was promoted to Senior Computer Scientist at Argonne. Butler officially retired in 1991, but continued to work at Argonne from 1993 to 2006 as a "special term appointee".
Impact.
During her time in Argonne, Butler was very supportive of her female coworkers. Women working at Argonne described her as a role model with a welcoming presence. According to Margaret's son Jay, she thought women were "given all the responsibilities and none of the authorities" and had to work "harder and smarter" yet were still not treated as individuals. When Butler rose in the ranks at Argonne, she made sure to hire women and recommend them for promotions. Margaret worked with other women to organize an Association for Women in Science in Chicago. While in AWIS, Margaret held executive board positions and led two conferences for high school students, teachers, and administration.


Revengers

The Revengers is the name of different fictional teams appearing in American comic books published by Marvel Comics.
Publication history.
The Revengers is a fictional team of supervillains who were formed to fight A-Next in the MC2 series "A-Next". They were created by Tom DeFalco and Ron Frenz.
The Revengers is also the name of a comical parody of The Avengers in Earth-665, the setting of Marvel's parody comic "Not Brand Echh".
In September 2011, an Earth-616 version of the Revengers led by Wonder Man appears. They were created by Brian Michael Bendis.
Fictional team history.
MC2.
After a tragic mission that claimed the life of several Avengers including Hank Pym and the Wasp, their children were furious to see A-Next, a team of heroes referred to by people as the "next generation of Avengers". The children of Hank Pym and Wasp used their parents' technology to replicate their powers. The daughter Hope Pym duplicated her mother's powers as the Red Queen while her brother Henry Pym Jr. copied his father's powers as Big Man.
Red Queen also helped create an energetic villain called Ion Man, whom she sent to kill Mainframe. Although he failed (unknowingly, since Mainframe was later rebuilt), he passed her test. Red Queen soon added more villains to her fold (Spider-Girl's nemesis, Killerwatt, and Wild Thing's homicidal half-brother Sabreclaw). She waited until the members of the Avengers were at their most vulnerable before sending her team, the Revengers, to destroy them. Red Queen herself wanted to personally torture Stinger, as she felt that Stinger dishonored her parents' memories, but the reserve members of A-Next defeated the Revengers and Big Man turned himself in, stopping his crazed sister, as Big Man did not want to be a killer.
However, in "Last Planet Standing", the Revengers returned with the aid of Magneta to fight A-Next again. The fight was halted when Galactus came to destroy Earth. A-Next teamed up with a number of other heroes while the Revengers got away, minus Sabreclaw, who stayed behind to help fight and later joined A-Next to help fill out their roster.
Cancerverse.
In the Cancerverse reality of Earth-10011, the Revengers were that reality's version of the Avengers who were corrupted by that reality's version of Captain Marvel who turned them into servants of the Many-Angled Ones. They were allies with the Defenders of the Realm and the Ex-Men. The Revengers were all destroyed when Thanos brought Death to this Deathless reality.
Earth-616.
In 2011, another version of the Revengers appear in the Earth-616 universe. Formed by Wonder Man (whose ionic energy leaking problem has caused him to become convinced that the Avengers are not helping the world and that he must stop them), it consists of lesser-known heroes who he has convinced to help him as this antihero group. During the Revengers attack on Avengers Mansion where they fought the New Avengers, Ms. Marvel tries to reason with Wonder Man which doesn't work. This team manages to defeat the New Avengers and they move on to attack Stark Tower. Wonder Man has Atlas attack Stark Tower to get their attention upon calling a press conference. After failing to reason with Wonder Man, Iron Man trapped him in a stasis container. When the Avengers do not want to fight with so many civilians nearby, Thor teleports the Revengers to Citi Field and all three teams (the main Avengers, the New Avengers, and the Secret Avengers) gang up on the Revengers all at once. With the Revengers imprisoned at the Raft, each member has been interrogated with Captain America, Thor, and Iron Man watching the video feed of the interrogation. Beast later visits Wonder Man in his stasis container. Wonder Man insists that he is acting of his own free will and remains steadfast in his claim that the Avengers must disband before more people are hurt. He also adds something new: his realization that Scarlet Witch created him and that he probably is not even real. Appealing to their friendship, Wonder Man tries to extract a promise from Beast to shut the Avengers down when he realizes that Wonder Man is in the right, but a distressed Beast walks away. Various news programs are buzzing about the Avengers' lack of transparency and stonewalling tactics. Some openly speculate that the time for a self-appointed hero team is over and done. In his bubble, Wonder Man smiles and vanishes into a white light.
New Revengers.
As part of the "All-New, All-Different Marvel", Maker of W.H.I.S.P.E.R. assembles a new incarnation of the Revengers dubbed the New Revengers with plans to have them face the New Avengers. They consist of Asti the All-Seeing, Paibok, Vermin, White Tiger, and alternate versions of Angar the Screamer and Skar.
During the "Civil War II" storyline, the New Revengers gain City's O.M.N.I.T.R.O.C.U.S form as its latest member. At the time when A.I.M. was facing off against S.H.I.E.L.D., Maker took advantage of this by sending his New Revengers to attack them. While O.M.N.I.T.R.O.C.U.S. kept Sunspot trapped in his office while having his own defense system attack him, Angela del Toro fought with her aunt Ava Ayala while the other Revengers members attacked the rest of the New Avengers and the staff of Avengers Base Two. Donning a variation of Pepper Potts' Rescue armor, Toni Ho managed to slay the alternate Skar. Also, Mockingbird managed to get free from O.M.N.I.T.R.O.C.U.S.' clutches with the help of Warlock while Ava broke Angela free from the combined influences of the Tiger God and the Hand. The remaining members of the New Revengers faced off against the New Avengers and the rest of the A.I.M. staff. While the remaining members of the New Revengers were defeated, Maker got away.
In other media.
The Revengers is the name of a team that appears in the Marvel Cinematic Universe 2017 film "". The team is assembled by Thor out of necessity to escape the Grandmaster's domain and includes Thor himself, Valkyrie, Hulk and Loki with Korg, and Miek as associates. Thor appears to make up the name on the spot as he tries to reason that they all want revenge, though Banner claims that he is "undecided", Thor knowing that they can't use the proper term of Avengers as that name is taken, with himself and Banner as founding members. After making it to Asgard and confronting Hela, who makes short work of them, Thor quips that they should probably disband the Revengers.


Primary School Achievement Test (Malaysia)

Primary School Achievement Test, also known as Ujian Pencapaian Sekolah Rendah (commonly abbreviated as UPSR; Malay), was a national examination taken by all students in Malaysia at the end of their sixth year in primary school before they leave for secondary school. It is prepared and examined by the Malaysian Examinations Syndicate (Lembaga Peperiksaan Malaysia), an agency that constitutes the Ministry of Education.
The UPSR tests were first established in 1988 to replace the Standard Five assessment.
Starting from 2016, students in national schools (sekolah kebangsaan) are required to take six subjects. Students in Chinese and Tamil national-type schools (sekolah jenis kebangsaan) are required to take two additional language subjects, totalling eight subjects.
Multiple choice questions are tested using a standardised optical answer sheet that uses optical mark recognition for detecting answers.
This exam is held annually on the first Monday of September. The score is calculated based on a bell curve, thus the passing grade is reflected by the yearly performance.
Effective 2021, the UPSR exams were abolished and replaced with school-based assessments, seeing it suffer the same fate as the PMR examinations.
Subjects.
The subjects that are taken in this exam include:
Each of the two Bahasa Malaysia subjects is offered at two different levels: the harder SK level and the easier SJK level, due to the difference in the Bahasa Malaysia syllabus taught in SK and SJK. However, SJK students may opt to sit for the SK paper with permission from their schools.
Mathematics.
In 1995, UPSR Mathematics tests were changed to include subjective questions.
The mathematics examination is divided into two papers, paper 1 and paper 2.
Starting from 2016, the exam is one hour long for each paper. Paper 1 is a multiple choice paper and consists of forty questions, all have a one-point score value. Paper 2 is the subjective area of Maths. There are 15 questions here in total, the first five questions have a three-point score value, questions 6-10 have a four-point score value, and the last five have a five-point score value.
Questions that are frequently asked in this exam are fractions, subtraction, multiplication, division, addition, area and volume, mass, perimeter, decimal points, average, data, digit numbers, percentage, money, time, date and duration.
Science.
Science was first made a part of the UPSR in 1997.
Starting from 2016, the science examination is divided into two papers, paper 1 and paper 2. Each paper lasts for an hour.
For paper 1, students are given 40 multiple choice questions with a weight of one mark each. For paper 2, students answer subjective questions. In the subjective paper, there are eight questions and each question has 3 to 5 sub-questions which carry 1 to 3 marks depending on the question. The total weight that can be given here is 40.
Examining and result.
After the completion of all exams, the examination papers will be brought to centres across the country to be evaluated. The distribution of papers across all the states can be random or otherwise, according to the wishes of the invigilator. All objective answer sheets are examined by computer, and all subjective answer sheets are marked by professional examiners. After completion the examination of all papers, the marks will be registered into an online system. A council will be called to ascertain the specific marks for the grade of each subject (the standard mark for an 'A' grade is 80 and above, however, should the year's cohort perform badly, the marks may be lowered to 70+ and above for an 'A'). It also may be 85+ for an A.The results are then printed and distributed to the education department of every district. Usually, the results are announced on the last Thursday of the school year (it is the second-last day of school for all states except Terengganu, Kelantan,Kedah and Johor where it is the final day of school for the year), but in some years, it is published during the school holidays.
A new grading scheme was introduced in 2016 as below:
A: 80-100
B: 65-79
C: 50-64
D: 40-49
E: 0-39
Grade E is the only failing grade for all subjects.
Format change.
In 2016, several changes were made to the format of all the important subjects :
Pemahaman.
The "Pemahaman" paper has 2 sections, A and B. Section A has 20 objective questions for 40 marks and Section B has 5 questions for 60 marks.This exam lasted for 1 hour and 15 minutes.
Penulisan.
The new format for "Penulisan" consists of three sections, namely A, B and C. The time allowed is one hour and fifteen minutes.
For section A, a picture will be given. Then, pupils must build five compound sentences based on the picture. The marks allocated for this section is 20. Occasionally, however, pictures might not be provided and to substitute that, candidates might be asked to write sentences about a graph, a mind map, multiple images, or a time table.
For section B, candidates must write a review about the stimulus given to be written on the UPSR paper. The marks allocated for this section is 30 marks.
For Section C, The student must choose one out of two questions and write an essay of between 60 and 100 words.The marks allocated for this section is 50 marks.
English.
English now has Comprehension and Writing papers, unlike the previous single paper.
The questions in the Comprehension paper are grouped into two sections: A with 20 multiple choice questions dealing with Grammar, Vocabulary and Comprehension; and B with 5 questions, dealing with Social expressions, Comprehension, and HOTS (Higher Order Thinking Skills)
2014 paper leak.
On 10 September 2014, the Examinations Syndicate had made a statement stating that instead of the Science paper(018, 028, 038) being sat the next day, it would be postponed to 30 September. The reason given for the postponement was due to the fact that the question paper was leaked on social media. A few days later, another statement had been made saying that the English paper(014) has also been leaked and will be sat on the same day. About a week later, the Education Ministry announced that the Tamil(036, 037) and Maths (Paper 1(015/1, 025/1, 035/1)) papers were also found to be hacked, and would be sat on 9 October.
2021 abolishment.
On 28 April 2021, Senior Minister of Education and Society and Minister of Education Mohd Radzi Md Jidin announced through a press conference that the UPSR exam will be abolished from 2021 onwards. He also said that students will be evaluated using school-based assessments, a system which had been in effect since 2011. Talk of abolishing the examination had began in 2016 when the then-Education Minister, Mahdzir Khalid said that a study was being done to evaluate the future of UPSR.


357 Ninina

Ninina (minor planet designation: 357 Ninina) is a large main-belt asteroid. It was discovered by Auguste Charlois on February 11, 1893, in Nice.
The reference of its name is not known, though "Ninine" is a French personal name.


2223 Sarpedon

2223 Sarpedon is a dark Jupiter trojan from the Trojan camp, approximately in diameter. It was discovered on 4 October 1977, by astronomers at the Purple Mountain Observatory near Nanking, China. The D-type asteroid belongs to the 30 largest Jupiter trojans and has a rotation period of 22.7 hours. It was named after the Lycian hero Sarpedon from Greek mythology.
Orbit and classification.
"Sarpedon" is orbiting in the trailing Trojan camp, at Jupiter's Lagrangian point, 60° behind its orbit in a 1:1 resonance . It is also a non-family asteroid of the Jovian background population.
It orbits the Sun at a distance of 5.2–5.3 AU once every 11 years and 12 months (4,376 days; semi-major axis of 5.24 AU). Its orbit has an eccentricity of 0.02 and an inclination of 16° with respect to the ecliptic. The body's observation arc begins with its official discovery observation at Nanking.
Physical characteristics.
In the Tholen classification, "Sarpedon" is similar to a dark D-type asteroid, though with an unusual spectrum (DU).
Rotation period.
In April 1996, a rotational lightcurve of "Sarpedon" was obtained from photometric observations by Italian astronomer Stefano Mottola at ESO's La Silla Observatory using the Bochum 0.61-metre Telescope. Lightcurve analysis gave a rotation period of 22.741 hours with a brightness amplitude of 0.14 magnitude (). A previous observation by Mottola gave a similar period of 22.77 hours from a lower-rated lightcurve ().
Diameter and albedo.
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, "Sarpedon" measures between 77.48 and 108.21 kilometers in diameter and its surface has an albedo between 0.027 and 0.051.
The "Collaborative Asteroid Lightcurve Link" adopts the results obtained by IRAS, that is, an albedo of 0.034 and a diameter of 94.63 kilometers based on an absolute magnitude of 9.41.
Naming.
This minor planet was named from Greek mythology after the Lycian hero Sarpedon from the "Iliad", who was killed by Patroclus, during the Trojan War. The official naming citation was published by the Minor Planet Center on 1 August 1981 ().


List of nearest exoplanets

There are known exoplanets, or planets outside the Solar System that orbit a star, as of ; only a small fraction of these are located in the vicinity of the Solar System. Within , there are 97 exoplanets listed as confirmed by the NASA Exoplanet Archive. Among the over 400 known stars within 10 parsecs, around 60 have been confirmed to have planetary systems; 51 stars in this range are visible to the naked eye, nine of which have planetary systems.
The first report of an exoplanet within this range was in 1998 for a planet orbiting around Gliese 876 (15.3 light-years (ly) away), and the latest as of 2020 is one around AU Microscopii (32 ly). The closest exoplanet found is Proxima Centauri b, which was confirmed in 2016 to orbit Proxima Centauri, the closest star to the Solar System (4.25 ly). HD 219134 (21.6 ly) has six exoplanets, the highest number discovered for any star within this range.
Most known nearby exoplanets orbit close to their stars. A majority are significantly larger than Earth, but a few have similar masses, including two planets (around YZ Ceti, 12 ly) which may be less massive than Earth. Several confirmed exoplanets are hypothesized to be potentially habitable, with Proxima Centauri b and Gliese 667 Cc (23.6 ly) considered among the most likely candidates. The International Astronomical Union took a public survey in 2015 to assign proper names to some known extrasolar bodies, including the planets around Epsilon Eridani (10.5 ly) and Fomalhaut.
Exoplanets within 10 parsecs.
Excluded objects.
Unlike for bodies within the Solar System, there is no clearly established method for officially recognizing an exoplanet. According to the International Astronomical Union, an exoplanet should be considered confirmed if it has not been disputed for five years after its discovery. There have been examples where the existence of exoplanets has been proposed, but even after follow-up studies their existence is still considered doubtful by some astronomers. Such cases include LHS 288 (15.6 ly, in 2007). There are also some instances where proposed exoplanets were later disproved by subsequent studies, including candidates around Alpha Centauri B (4.36 ly), Van Maanen 2 (13.9 ly), Groombridge 1618 (15.9 ly), AD Leonis (16.2 ly), Gliese 682 (16.6 ly), VB 10 (18.7 ly), and Fomalhaut (25.1 ly).
In 2021, a candidate planet was detected around Vega, though it has yet to be confirmed. Another candidate planet, Candidate 1, was directly imaged around Alpha Centauri A, though it may also be a clump of asteroids or an artifact of the discovery mechanism.
The Working Group on Extrasolar Planets of the International Astronomical Union adopted in 2003 a working definition on the upper limit for what constitutes a planet: not being massive enough to sustain thermonuclear fusion of deuterium. Some studies have calculated this to be somewhere around 13 times the mass of Jupiter, and therefore objects more massive than this are usually classified as brown dwarfs. Some proposed candidate exoplanets were later shown to be massive enough to fall above the threshold, and are likely brown dwarfs, as was the case for: SCR 1845-6357 B (12.6 ly), SDSS J1416+1348 B (29.7 ly), and WISE 1217+1626 B (30 ly).
Excluded from the current list are known examples of potential free-floating sub-brown dwarfs, or "rogue planets", which are bodies that are too small to undergo fusion yet they do not revolve around a star. Known such examples include: WISE 0855–0714 (7.3 ly), UGPS 0722-05, (13 ly) WISE 1541−2250 (18.6 ly), and SIMP J01365663+0933473 (20 ly).


Udaipur Solar Observatory

The Udaipur Solar Observatory (USO) is in Udaipur, Rajasthan in India on an island in the Fateh Sagar Lake. The sky conditions at Udaipur are quite favourable for solar observations. Since the observatory is situated amidst a large mass of water, air turbulence which occurs due to ground heating by sun's rays is decreased. This improves the image quality and accuracy (average between 1-2 arc seconds).
History.
The observatory was built in 1976 by Dr. Arvind Bhatnagar following the model of the Solar Observatory at Big Bear lake in Southern California. Later, he was joined by Dr. Ashok Ambastha in 1983 and subsequently by many others at different stages who have continued further contributing to the growth of this observatory.
Telescopes.
Utilizing a variety of telescopes, USO is known for its solar observations, which include high-resolution solar chromospheric, magnetic field, velocity, and spectral observations, for studies pertaining to solar flares, mass ejections, and the evolution of solar active regions. USO fills the large longitudinal gap between Australia and Spain, and provides a link for continuous solar coverage in international collaborative programs, including the Global Oscillations Network Group (GONG). Since 1981, USO has been managed by the Physical Research Laboratory, Ahmedabad, for the Department of Space, Government of India.
Multi Application Solar Telescope (MAST).
The Multi Application Solar Telescope (MAST) was operationalised on 4 August 2015. MAST is an off-axis Gregorian-Coude telescope with a 50 cm aperture to be used to study the Sun's magnetic field.


Liquid apogee engine

A liquid apogee engine (LAE), or apogee engine, refers to a type of chemical rocket engine typically used as the main engine in a spacecraft.
The name "apogee engine" derives from the type of manoeuvre for which the engine is typically used, i.e. an in-space delta-"v" change made at the apogee of an elliptical orbit in order to circularise it. For geostationary satellites, this type of orbital manoeuvre is performed to transition from a geostationary transfer orbit and place the satellite on station in a circular geostationary orbit. Despite the name, an apogee engine can be used for a range of other manoeuvres, such as end-of-life deorbit, Earth orbit escape, planetary orbit insertion and planetary descent/ascent.
In some parts of the space industry an LAE is also referred to as a liquid apogee motor (LAM), a liquid apogee thruster (LAT) and, depending on the propellant, a dual-mode liquid apogee thruster (DMLAT). Despite the ambiguity with respect to the use of "engine" and "motor" in these names, all use liquid propellant. An apogee kick motor (AKM) or apogee boost motor (ABM) such as the Waxwing, however, uses solid propellant. These solid-propellant versions are not used on new-generation satellites.
History.
The apogee engine traces its origin to the early 1960s, when companies such as Aerojet, Rocketdyne, Reaction Motors, Bell Aerosystems, TRW Inc. and The Marquardt Company were all participants in developing engines for various satellites and spacecraft.
Derivatives of these original engines are still used today and are continually being evolved and adapted for new applications.
Layout.
A typical liquid apogee engine scheme could be defined as an engine with:
To protect the spacecraft from the radiant heat of the combustion chamber, these engines are generally installed together with a heat shield.
Propellant.
Apogee engines typically use one fuel and one oxidizer. This propellant is usually, but not restricted to, a hypergolic combination such as:
Hypergolic propellant combinations ignite upon contact within the engine combustion chamber and offer very high ignition reliability, as well as the ability for reignition.
In many instances mixed oxides of nitrogen (MON), such as MON-3 ( with 3 wt% ), is used as a substitute for pure .
The use of is under threat in Europe due to REACH regulations. In 2011 the REACH framework legislation added to its candidate list of "substances of very high concern". This step increases the risk that the use of will be prohibited or restricted in the near- to mid-term.
Exemptions are being sought to allow to be used for space applications, however to mitigate this risk, companies are investigating alternative propellants and engine designs. A change over to these alternative propellants is not straightforward, and issues such as performance, reliability and compatibility (e.g. satellite propulsion system and launch-site infrastructure) require investigation.
Performance.
The performance of an apogee engine is usually quoted in terms of vacuum specific impulse and vacuum thrust. However, there are many other details which influence performance:
A typical 500 N-class hypergolic liquid apogee engine has a vacuum specific impulse in the region of 320 s, with the practical limit estimated to be near 335 s.
Though marketed to deliver a particular nominal thrust and nominal specific impulse at nominal propellant feed conditions, these engines actually undergo rigorous testing where performance is mapped over a range of operating conditions before being deemed "flight-qualified". This means that a flight-qualified production engine can be tuned (within reason) by the manufacturer to meet particular mission requirements, such as higher thrust.
Operation.
Most apogee engines are operated in an on–off manner at a fixed thrust level. This is because the valves used only have two positions: open or closed.
The duration for which the engine is on, sometimes referred to as the "burn duration", depends both on the manoeuvre and the capability of the engine. Engines are qualified for a certain minimal and maximal single-burn duration.
Engines are also qualified to deliver a maximal cumulative burn duration, sometimes referred to as "cumulative propellant throughput". The useful life of an engine at a particular performance level is dictated by the useful life of the materials of construction, primarily those used for the combustion chamber.
Applications.
A simplified division can be made between apogee engines used for telecommunications and exploration missions:
The actual engine chosen for a mission is dependent on the technical details of the mission. More practical considerations such as cost, lead time and export restrictions (e.g. ITAR) also play a part in the decision.


927 Ratisbona

927 Ratisbona is a large and dark background asteroid, approximately in diameter, located in the outer region of the asteroid belt. It was discovered on 16 February 1920, by astronomer Max Wolf at the Heidelberg Observatory in southwest Germany. The carbonaceous C-type asteroid (CB) has a rotation period of 12.99 hours and is rather spherical in shape. It was named after the Bavarian city of Regensburg.
Orbit and classification.
"Ratisbona" is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements. It orbits the Sun in the outer asteroid belt at a distance of 2.9–3.5 AU once every 5 years and 10 months (2,119 days; semi-major axis of 3.23 AU). Its orbit has an eccentricity of 0.09 and an inclination of 15° with respect to the ecliptic. The body's observation arc begins at Heidelberg-Königstuhl State Observatory on 17 February 1920, the night after its official discovery observation.
Naming.
This minor planet was named after the Latin name of the German city of Regensburg in Bavaria, where astronomer Johannes Kepler died in 1630. The was mentioned in the astronomical journal "Astronomische Nachrichten" in 1930 ().
Physical characteristics.
In the Tholen classification, "Ratisbona" is most similar to a common, carbonaceous C-type asteroid, and somewhat similar to a brighter B-type asteroid, based on a nosy spectrum (CB:).
Rotation period.
Over the course of seven nights in January 2018, a rotational lightcurve of "Ratisbona" was obtained from photometric observations by Tom Polakis at the Command Module Observatory in Arizona. Lightcurve analysis gave a rotation period of hours with a low brightness variation of magnitude, indicative of a regular, spherical shape (). The result supersedes a period of hours with an amplitude of magnitude determined by René Roy, Raoul Behrend, Pierre Antonini and Donn Starkey in October 2004 ().
Diameter and albedo.
According to the survey carried out by the Infrared Astronomical Satellite IRAS, the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer (WISE), and the Japanese Akari satellite, "Ratisbona" measures (), () and () kilometers in diameter and its surface has a very low albedo of (), () and (), respectively.
The "Collaborative Asteroid Lightcurve Link" adopts the results from IRAS, that is, a albedo of 0.0591 and a diameter of 67.57 km based on an absolute magnitude of 9.54. Further published mean-diameters and albedos by the WISE team include () and () and albedos of () and (). An asteroid occultation, observed on 13 September 2014, gave a best-fit ellipse dimension of 78.0 × 78.0 kilometers. These timed observations are taken when the asteroid passes in front of a distant star. However the quality of the measurement is rated poorly.


Blick am Abend

Blick am Abend was a German free evening newspaper published in Switzerland and based in Zürich.
History and profile.
"Blick am Abend" was first published on 1 June 2008 as a successor to the afternoon free daily "Heute".
"Blick am Abend", based in Zürich, was a free newspaper owned by Ringier. It was an evening newspaper published in tabloid format. Peter Röthlisberger was the editor-in-chief of the daily. Its sister newspaper was "Blick", a leading daily in the country.
In 2008 "Blick am Abend" started a biweekly legal column which answers the reader questions. Until 2009 the daily had editions in Zurich, Berne and Basle. St. Gallen and Luzern/Zug editions were started in 2009. In December 2013 the paper launched its online edition.
The audited circulation of "Blick am Abend" in 2008 was 211,000 copies. The paper had a circulation of 225,226 copies in 2009. In 2010 its circulation was 329,418 copies and its 2010 readership was 604,000.
"Blick am Abend" was discontinued in December 2018.


950 Ahrensa

950 Ahrensa, provisional designation , is a stony Phocaea asteroid and slow rotator from the inner regions of the asteroid belt, approximately 15 kilometers in diameter. It was discovered on 1 April 1921, by German astronomer Karl Reinmuth at Heidelberg Observatory in southern Germany.
Description.
The S-type asteroid, classified as a Sa-subtype in the SMASS taxonomic scheme, is a member of the Phocaea family, a group of asteroids with similar orbital characteristics. It orbits the Sun at a distance of 2.0–2.7 AU once every 3 years and 8 months (1,334 days). Its orbit shows an eccentricity of 0.16 and is tilted by 23 degrees to the plane of the ecliptic.
A photometric lightcurve analysis at the U.S. Palmer Divide Observatory in 2009, showed that the body has an exceptionally long rotation period of 202 hours. According to the surveys carried out by the Infrared Astronomical Satellite, IRAS, the Japanese Akari satellite, and the U.S. Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, the surface of the asteroid has an albedo in the range of 0.16 to 0.23, while the Collaborative Asteroid Lightcurve Link derives an even higher value of 0.27 for the stony body.
The minor planet was named in honor of friends of the discoverer Karl Reinmuth, the Ahrens family, who helped him financially at the Heidelberg Observatory. Reinmuth also named the minor planet 909 Ulla after Ulla Ahrens, a member of this family.


Atomic spectroscopy

Atomic spectroscopy is the study of the electromagnetic radiation absorbed and emitted by atoms. Since unique elements have characteristic (signature) spectra, atomic spectroscopy, specifically the electromagnetic spectrum or mass spectrum, is applied for determination of elemental compositions. It can be divided by atomization source or by the type of spectroscopy used. In the latter case, the main division is between optical and mass spectrometry. Mass spectrometry generally gives significantly better analytical performance, but is also significantly more complex. This complexity translates into higher purchase costs, higher operational costs, more operator training, and a greater number of components that can potentially fail. Because optical spectroscopy is often less expensive and has performance adequate for many tasks, it is far more common Atomic absorption spectrometers are one of the most commonly sold and used analytical devices.
Optical spectroscopy.
Electrons exist in energy levels (i.e. atomic orbitals) within an atom. Atomic orbitals are quantized, meaning they exist as defined values instead of being continuous (see: atomic orbitals). Electrons may move between orbitals, but in doing so they must absorb or emit energy equal to the energy difference between their atom's specific quantized orbital energy levels. In optical spectroscopy, energy absorbed to move an electron to a higher energy level (higher orbital) and/or the energy emitted as the electron moves to a lower energy level is absorbed or emitted in the form of photons (light particles). Because each element has a unique number of electrons, an atom will absorb/release energy in a pattern unique to its elemental identity (e.g. Ca, Na, etc.) and thus will absorb/emit photons in a correspondingly unique pattern. The type of atoms present in a sample, or the amount of atoms present in a sample can be deduced from measuring these changes in light wavelength and light intensity.
Optical spectroscopy is further divided into atomic absorption spectroscopy and atomic emission spectroscopy. In atomic absorption spectroscopy, light of a predetermined wavelength is passed through a collection of atoms. If the wavelength of the source light has energy corresponding to the energy difference between two energy levels in the atoms, a portion of the light will be absorbed. The difference between the intensity of the light emitted from the source (e.g., lamp) and the light collected by the detector yields an absorbance value. This absorbance value can then be used to determine the concentration of a given element (or atoms) within the sample. The relationship between the concentration of atoms, the distance the light travels through the collection of atoms, and the portion of the light absorbed is given by the Beer–Lambert law. In atomic emission spectroscopy, the intensity of the emitted light is directly proportional to the concentration of atoms.
Mass spectrometry.
Atomic mass spectrometry is similar to other types of mass spectrometry in that it consists of an ion source, a mass analyzer, and a detector. Atoms' identities are determined by their mass-to-charge ratio (via the mass analyzer) and their concentrations are determined by the number of ions detected. Although considerable research has gone into customizing mass spectrometers for atomic ion sources, it is the ion source that differs most from other forms of mass spectrometry. These ion sources must also atomize samples, or an atomization step must take place before ionization. Atomic ion sources are generally modifications of atomic optical spectroscopy atom sources.
Ion and atom sources.
Sources can be adapted in many ways, but the lists below give the general uses of a number of sources. Of these, flames are the most common due to their low cost and their simplicity. Although significantly less common, inductively-coupled plasmas, especially when used with mass spectrometers, are recognized for their outstanding analytical performance and their versatility.
For all atomic spectroscopy, a sample must be vaporized and atomized. For atomic mass spectrometry, a sample must also be ionized. Vaporization, atomization, and ionization are often, but not always, accomplished with a single source. Alternatively, one source may be used to vaporize a sample while another is used to atomize (and possibly ionize). An example of this is laser ablation inductively-coupled plasma atomic emission spectrometry, where a laser is used to vaporize a solid sample and an inductively-coupled plasma is used to atomize the vapor.
With the exception of flames and graphite furnaces, which are most commonly used for atomic absorption spectroscopy, most sources are used for atomic emission spectroscopy.
Liquid-sampling sources include flames and sparks (atom source), inductively-coupled plasma (atom and ion source), graphite furnace (atom source), microwave plasma (atom and ion source), and direct-current plasma (atom and ion source). Solid-sampling sources include lasers (atom and vapor source), glow discharge (atom and ion source), arc (atom and ion source), spark (atom and ion source), and graphite furnace (atom and vapor source). Gas-sampling sources include flame (atom source), inductively-coupled plasma (atom and ion source), microwave plasma (atom and ion source), direct-current plasma (atom and ion source), and glow discharge (atom and ion source).


Areosynchronous orbit

The areosynchronous orbits (ASO) are the synchronous orbits for artificial satellites around the planet Mars. They are the martian equivalent of the geosynchronous orbits (GSO) on the Earth. The prefix "areo-" derives from Ares, the ancient Greek god of war and counterpart to the Roman god Mars, with whom the planet was identified. The modern Greek word for Mars is "Άρης" (Áris).
As with all synchronous orbits, an areosynchronous orbit has an orbital period equal in length to the primary's sidereal day. A satellite in areosynchronous orbit does "not" necessarily maintain a fixed position in the sky as seen by an observer on the surface of Mars; however, such a satellite will return to the same apparent position every Martian day.
The orbital altitude required to maintain an areosynchonous orbit is approximately . If a satellite in areosynchonous orbit were to be used as a communication relay link, it "would experience communications ranges of " to various points on the visible Martian surface.
An areosynchronous orbit that is equatorial (in the same plane as the equator of Mars), circular, and prograde (rotating about Mars's axis in the same direction as the planet's surface) is known as an areostationary orbit (AEO). To an observer on the surface of Mars, the position of a satellite in AEO would appear to be fixed in a constant position in the sky. The AEO is analogous to a geostationary orbit (GEO) about Earth.
Although no satellites currently occupy areosynchronous or areostationary orbits, some scientists foresee a future telecommunications network for the exploration of Mars.


Coles 4038

The Coles 4038 is a ribbon microphone produced by Coles Electroacoustics. The microphone was designed and patented by the BBC in the 1950s and was originally known as the STC 4038. The sound of the microphone has been described as "British" with a "BBC politeness", and its appearance has been likened to that of a waffle iron. It is used in both sound recording and radio broadcasting.
History.
The microphone was designed by the BBC in 1953 and the prototype was assigned the model number BBC PGS/1. It was designed as a result of the BBC's request for a strong and affordable microphone that was smaller than previous models (such as the Type A). The 4038 was an improvement on the Type A's frequency response, and was described as "less obtrusive".
The microphone was produced by Standard Telephones and Cables before their manufacturing was transferred to Coles in the mid-1970s. Since its design in the 1950s, the technical specifications of the 4038 have remained unchanged.
Use.
Recording.
In recording environments, the 4038 is often used as drum overheads and on brass instruments. The microphone became a favourite of British recording engineers in the 1950s and 60s, but did not receive widespread use in the United States. The microphone was described as recording sounds "bigger than
life" – such as drums or amplified guitars – some Beatles and Led Zeppelin recordings featured 4038s as overhead microphones on the drum kit.
In a 1994 interview, Steve Albini said that "if [he] owned one mic, this would be it". Albini has also commented that "really nothing beats them as an overhead on a drum kit".
Broadcast.
At one point, Bush House (home of the BBC World Service) used the 4038 almost exclusively.
Technical.
The 4038's frequency response is flat, with a range of approximately 30–15,000 Hz. The attenuation of high frequencies reduces sibilance on vocals, but also reduces detail.
The microphone uses a bi-directional polar pattern.
The microphone is connected using a Western Electric jack connector designated 4069, which adapts the microphone's 3-pin output to a standard XLR connector.


Countries in the International Organization for Standardization

There are, , 165 members of the International Organization for Standardization. Three types of membership status can be distinguished:


2509 Chukotka


2879 Shimizu


969 Leocadia

969 Leocadia ("prov. designation:" "or" ) is a very dark background asteroid from the inner regions of the asteroid belt, approximately in diameter. It was discovered on 5 November 1921, by Russian astronomer Sergey Belyavsky at the Simeiz Observatory on the Crimean peninsula. The uncommon F-type asteroid (FX) has a rotation period of 6.9 hours and is likely regular in shape. Any reference of the asteroid's name to a person is .
Orbit and classification.
"Leocadia" is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements. It orbits the Sun in the inner main-belt at a distance of 2.0–3.0 AU once every 3 years and 10 months (1,411 days; semi-major axis of 2.46 AU). Its orbit has an eccentricity of 0.21 and an inclination of 2° with respect to the ecliptic. The body's observation arc begins at Uccle Observatory in February 1933, more than a decade after its official discovery observation Simeiz Observatory on 5 November 1921.
Naming.
This minor planet is named after a Feminine Russian first name. Any reference of this name to a person or occurrence is unknown.
Unknown meaning.
Among the many thousands of named minor planets, "Leocadia" is one of 120 asteroids, for which no official naming citation has been published. All of these low-numbered asteroids have numbers between and and were discovered between 1876 and the 1930s, predominantly by astronomers Auguste Charlois, Johann Palisa, Max Wolf and Karl Reinmuth "(also see )".
Physical characteristics.
In the Tholen classification (FXU:), "Leocadia" is an uncommon and dark F-type asteroid, somewhat similar to that of an X-type, though with an unusual (U) and noisy (:) spectra.
Rotation period.
In December 2006, a rotational lightcurve of "Leocadia" was obtained from photometric observations by Italian amateur astronomers Roberto Crippa and Federico Manzini at the Sozzago Astronomical Station . Lightcurve analysis gave a rotation period of hours with a brightness amplitude of magnitude (), which is indicative of a rather spherical, non-irregular shape.
Diameter and albedo.
According to the surveys carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer (WISE), the Japanese Akari satellite, and the Infrared Astronomical Satellite IRAS, "Leocadia" measures , and kilometers in diameter, and its surface has a very low albedo of , and , respectively. Additional measurements by the WISE telescope were published giving a mean-diameter as low as . The "Collaborative Asteroid Lightcurve Link" adopts the result from IRAS, that is, an albedo of 0.0435 and a diameter of 19.51 kilometers based on an absolute magnitude of 9.22.
An asteroid occultation on 19 August 2013, gave a best-fit ellipse dimension of 19.0 × 19.0 kilometers. These timed observations are taken when the asteroid passes in front of a distant star. However the measurements for "Leocadia" were of poor quality.