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Topic Review
Aries
Aries, recognized by the International Astronomical Union (IAU), is a constellation in the northern celestial hemisphere. Representing the ram from ancient Greek mythology, Aries is one of the twelve zodiac constellations and holds significance in astrology and astronomy alike. Its celestial prominence and position along the ecliptic make it a notable feature in the night sky, marking the vernal equinox and heralding the beginning of spring in the northern hemisphere.
  • 136
  • 29 Feb 2024
Topic Review
ASTER (Spacecraft)
ASTER is a planned space mission under development by the Brazilian Space Agency that will launch a spacecraft to orbit a near-Earth object known as (153591) 2001 SN263, a triple asteroid system. The launch is scheduled for 2025, with a rendezvous in 2024/2027. According to de Brum et al. 2021, the launch is planned for June 2022 (asteroid arrival in December 2024) or June 2025 (arrival September 2027).
  • 354
  • 15 Nov 2022
Topic Review
Asterism
An asterism is an observed pattern or group of stars in the sky. Asterisms can be any identified pattern or group of stars, and therefore are a more general concept than the formally defined 88 constellations. Constellations are based on asterisms, but unlike asterisms, constellations outline and today completely divide the sky and all its celestial objects into regions around their central asterisms. For example, the asterism known as the Big Dipper comprises the seven brightest stars in the constellation Ursa Major. Another is the asterism of the Southern Cross, within the constellation of Crux. Asterisms range from simple shapes of just a few stars to more complex collections of many stars covering large portions of the sky. The stars themselves may be bright naked-eye objects or fainter, even telescopic, but they are generally all of a similar brightness to each other. The larger brighter asterisms are useful for people who are familiarizing themselves with the night sky. The patterns of stars seen in asterisms are not necessarily a product of any physical association between the stars, but are rather the result of the particular perspectives of their observations. For example the Summer Triangle is a purely observational physically unrelated group of stars, but the stars of Orion's Belt are all members of the Orion OB1 association and five of the seven stars of the Big Dipper are members of the Ursa Major Moving Group. Physical associations, such as the Hyades or Pleiades, can be asterisms in their own right and part of other asterism at the same time.
  • 1.1K
  • 29 Nov 2022
Topic Review
Astrobiology Science and Technology for Exploring Planets
Astrobiology Science and Technology for Exploring Planets (ASTEP) was a program established by NASA to sponsor research projects that advance the technology and techniques used in planetary exploration. The objective was to enable the study of astrobiology and to aid the planning of extraterrestrial exploration missions while prioritizing science, technology, and field campaigns.
  • 439
  • 06 Oct 2022
Topic Review
Astronomy in the Medieval Islamic World
Islamic astronomy comprises the astronomical developments made in the Islamic world, particularly during the Islamic Golden Age (9th–13th centuries), and mostly written in the Arabic language. These developments mostly took place in the Middle East, Central Asia, Al-Andalus, and North Africa, and later in the Far East and India. It closely parallels the genesis of other Islamic sciences in its assimilation of foreign material and the amalgamation of the disparate elements of that material to create a science with Islamic characteristics. These included Greek, Sassanid, and Indian works in particular, which were translated and built upon. Islamic astronomy played a significant role in the revival of Byzantine and European astronomy following the loss of knowledge during the early medieval period, notably with the production of Latin translations of Arabic works during the 12th century. Islamic astronomy also had an influence on Chinese astronomy and Malian astronomy. A significant number of stars in the sky, such as Aldebaran, Altair and Deneb, and astronomical terms such as alidade, azimuth, and nadir, are still referred to by their Arabic names. A large corpus of literature from Islamic astronomy remains today, numbering approximately 10,000 manuscripts scattered throughout the world, many of which have not been read or catalogued. Even so, a reasonably accurate picture of Islamic activity in the field of astronomy can be reconstructed.
  • 9.8K
  • 24 Nov 2022
Topic Review
Astrophysics Data System
The SAO/NASA Astrophysics Data System (ADS) is an online database of over 16 million astronomy and physics papers from both peer reviewed and non-peer reviewed sources. Abstracts are available free online for almost all articles, and full scanned articles are available in Graphics Interchange Format (GIF) and Portable Document Format (PDF) for older articles. It was developed by the National Aeronautics and Space Administration (NASA), and is managed by the Smithsonian Astrophysical Observatory. ADS is a powerful research tool and has had a significant impact on the efficiency of astronomical research since it was launched in 1992. Literature searches that previously would have taken days or weeks can now be carried out in seconds via the ADS search engine, which is custom-built for astronomical needs. Studies have found that the benefit to astronomy of the ADS is equivalent to several hundred million US dollars annually, and the system is estimated to have tripled the readership of astronomical journals. Use of ADS is almost universal among astronomers worldwide, and therefore ADS usage statistics can be used to analyze global trends in astronomical research. These studies have revealed that the amount of research an astronomer carries out is related to the per capita gross domestic product (GDP) of the country in which he/she is based, and that the number of astronomers in a country is proportional to the GDP of that country, so the total amount of research done in a country is proportional to the square of its GDP divided by its population.
  • 490
  • 28 Oct 2022
Topic Review
AT2018cow
Coordinates: 16h 16m 00.2242 s, +22° 16′ 04.890 ″ AT2018cow (ATLAS name: ATLAS18qqn; also known as Supernova 2018cow, SN 2018cow, and "The Cow") was a very powerful astronomical explosion, 10 – 100 times brighter than a normal supernova, spatially coincident with galaxy CGCG 137-068, approximately 200 million ly (60 million pc) distant in the Hercules constellation. It was first detected on 16 June 2018 by the ATLAS-HKO telescope, and had generated significant interest among astronomers throughout the world. Later, on 10 July 2018, and after AT2018cow had significantly faded, astronomers, based on followup studies with the Nordic Optical Telescope (NOT), formally described AT2018cow as SN 2018cow, a type Ib supernova, showing an "unprecedented spectrum for a supernova of this class"; although others, mostly at first but also more recently, have referred to it as a type Ic-BL supernova. An explanation to help better understand the unique features of AT2018cow has been presented.
  • 419
  • 19 Oct 2022
Topic Review
Atmospheric Transparency at Candidate Sites for Sub-Millimeter-Wave Telescopes
Radio astronomical observations at millimeter and submillimeter wavelengths are a very important tool for astrophysical research. However, there is a huge area in northeastern Eurasia, including the whole Russian territory, which lacks sufficiently large radio telescopes effectively operating at these wavelengths. 
  • 173
  • 03 Nov 2023
Topic Review
Auriga
Auriga, an IAU-recognized constellation, lies in the northern celestial hemisphere. Notable for its pentagonal shape, it encompasses several bright stars, including Capella. This constellation is visible during winter and contains various deep-sky objects like star clusters and nebulae.
  • 148
  • 29 Feb 2024
Topic Review Video
Black Hole
Black holes are the celestial objects existing at the center of every galaxy. They can currently only be described by their spin, charge, and angular momentum, with other attributes derived from the basic properties. The existence of black holes was first predicted by German physicist and astronomer Karl Schwarzschild in 1916, with the exact solutions to Einstein's field equations of general relativity one year after its publication. Finnish physicist Gunnar Nordström proposed a theory of gravity and electromagnetism with four spatial dimensions in 1914, and later developed into the stationary charged black hole in 1918.
  • 518
  • 15 Oct 2023
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