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Topic Review
Taurus
Taurus, Latin for "the Bull," is a prominent constellation in the northern celestial hemisphere, easily recognizable for its V-shaped cluster of stars that form the bull's face and horns. Positioned along the ecliptic, Taurus holds cultural significance dating back to ancient civilizations, with associations ranging from agricultural symbolism to mythological tales of gods and heroes. Among its most famous features is the bright red star Aldebaran, known as the "Eye of the Bull".
  • 1.8K
  • 15 Mar 2024
Topic Review
(469219) 2016 HO3
(469219) 2016 HO3 is a micro-asteroid, fast rotator and near-Earth object of the Apollo group, approximately 41 meters in diameter. It is currently the smallest, closest, and most stable (known) quasi-satellite of Earth. The asteroid was discovered by Pan-STARRS at Haleakala Observatory on 27 April 2016.
  • 1.8K
  • 03 Nov 2022
Topic Review
Ursa Major Moving Group
The Ursa Major Moving Group, also known as Collinder 285 and the Ursa Major association, is the closest stellar moving group – a set of stars with common velocities in space and thought to have a common origin in space and time. In the case of the Ursa Major group, all the stars formed about 300 million years ago. Its core is located roughly 80 light years away and part of the Local Bubble. It is rich in bright stars including most of the stars of the Big Dipper.
  • 1.7K
  • 14 Oct 2022
Topic Review
Yajnavalkya's 95 Years Cycle of Synchronisation
Yajnavalkya's 95 Years Cycle of Synchronisation is the model proposed by the great Indian philosopher Yajnavalkya which explains the mathematical concept of the synchronisation of the motions of the Sun and the Moon. Yajnavalkya invented the 95 years of the periodic cycle, when the solar and lunar motions get synchronised. This 95 years of the periodic cycle is also known as Yajnavalkya Cycle. 
  • 1.7K
  • 25 Dec 2023
Topic Review
Microscopium
Microscopium is a small and faint constellation located in the southern celestial hemisphere. It was first introduced by the French astronomer Nicolas Louis de Lacaille during the 18th century, who named it in honor of the microscope, reflecting the era's burgeoning interest in scientific instrumentation. Despite its modest visibility, it contains several notable celestial objects, including a few galaxies and a planetary nebula.
  • 1.7K
  • 15 Mar 2024
Topic Review
Stellar Chromospheric Variability
Chromospheric (magnetic) activity is evidence of the presence of strong and variable magnetic fields. Magnetically active chromospheres are predominantly found in cool stars with convective envelopes of spectral types F and later. Day- to year-long variability is associated with the evolution and rotational modulation of individual magnetically active regions.
  • 1.7K
  • 12 Jan 2022
Topic Review
(594913) 2020 AV2
(594913) 2020 AV2, provisionally designated: 2020 AV2, is a large near-Earth asteroid discovered by the Zwicky Transient Facility on 4 January 2020. It is the first asteroid discovered to have an orbit completely within Venus's orbit, and is thus the first and only known member of the inner-Venusian provisionally-named Vatira population of Atira-class asteroids. 2020 AV2 has the smallest known aphelion and third-smallest known semi-major axis among all asteroids. With an absolute magnitude approximately 16.2, the asteroid is expected to be larger than 1 km in diameter.
  • 1.7K
  • 21 Oct 2022
Topic Review
Five Hundred Meter Aperture Spherical Telescope
The Five-hundred-meter Aperture Spherical radio Telescope (FAST; Chinese: 五百米口径球面射电望远镜), nicknamed Tianyan (天眼, lit. "Heavenly Eye" or "The Eye of Heaven") is a radio telescope located in the Dawodang depression (大窝凼洼地), a natural basin in Pingtang County, Guizhou Province, southwest China. It consists of a fixed 500 m (1,600 ft) diameter dish constructed in a natural depression in the landscape. It is the world's largest filled-aperture radio telescope, and the second-largest single-dish aperture after the sparsely-filled RATAN-600 in Russia. It has a novel design, using an active surface made of metal panels that can be tilted by a computer to help change the focus to different areas of the sky. The cabin containing the feed antenna suspended on cables above the dish is also moved using a digitally-controlled winch by the computer control system to steer the instrument to receive from different directions. Construction on the FAST project began in 2011 and it achieved first light in September 2016. It is currently undergoing testing and commissioning. It observes at wavelengths of 10 cm to 4.3 m.:11 The telescope made its first discovery of two new pulsars in August 2017, barely one year after its first light. The new pulsars PSR J1859-01 and PSR J1931-02, which are also referred to as FAST pulsar #1 and #2 (FP1 and FP2), were detected on 22 and 25 August and are 16,000 and 4,100 light years away, respectively. They were independently confirmed by the Parkes Observatory in Australia on 10 September. The telescope had discovered 44 new pulsars by September, 2018.
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  • 14 Oct 2022
Topic Review
Musca
Musca, Latin for "the fly," is a small constellation located in the southern celestial hemisphere. Representing a common household insect, Musca is one of the 12 constellations introduced by the Dutch astronomer Petrus Plancius in the late 16th century. 
  • 1.7K
  • 15 Mar 2024
Topic Review
Grus
Grus, the crane, is a constellation in the southern celestial hemisphere. Named after the crane bird in Greek mythology, it is one of twelve constellations conceived by the Dutch astronomer Petrus Plancius.
  • 1.7K
  • 15 Mar 2024
Topic Review
The TACTIC Telescope
The TACTIC (TeV Atmospheric Cherenkov Telescope with Imaging Camera) is a ground-based gamma-ray telescope in India. The telescope was set up at Mount Abu (24.6∘ N, 72.7∘ E, 1300 m above sea level)  in 1997. The operating principle of TACTIC is based on the imaging atmospheric Cherenkov technique for indirect observation of the gamma-ray sky. Since its first light in 1997, the TACTIC telescope has been employed to explore the Universe at TeV energies and several outstanding results are derived from the TACTIC data.  
  • 1.7K
  • 28 Apr 2021
Topic Review
Plutoid
A plutoid or ice dwarf is a trans-Neptunian dwarf planet, i.e. a body orbiting beyond Neptune that is massive enough to be rounded in shape. The term plutoid was adopted by the International Astronomical Union (IAU) working group Committee on Small Bodies Nomenclature, but was rejected by the IAU working group Planetary System Nomenclature. The term plutoid is not widely used by astronomers, though ice dwarf is not uncommon. There are thought to be thousands of plutoids in the Solar System, although only four have been formally designated as such by the IAU. The IAU developed this category of astronomical objects as a consequence of its 2006 resolution defining the word "planet". The IAU's formal definition of "plutoid", announced 11 June 2008, is: In light of the difficulty of remotely ascertaining hydrostasis, the IAU only formally confers "dwarf planet" (and by extension, "plutoid") status to those bodies whose minimum estimated size is substantially greater than what is generally thought necessary to guarantee hydrostatic equilibrium. (As of 2009), Pluto, Eris, Haumea, and Makemake are the only objects officially recognized as plutoids, while upwards of seventy more bodies that currently lack formal recognition are thought likely to meet the definition, and can expect formal recognition at some time in the future. Alan Stern of the Southwest Research Institute believes the outer planets show signs of collisions with plutoids 1,000 to 2,000 kilometers in diameter: Uranus could have been tipped off its axis by a plutoid, and Triton, the largest moon of Neptune, is probably a captured plutoid from the Kuiper belt.
  • 1.7K
  • 21 Nov 2022
Topic Review
Delphinus
Delphinus, commonly known as the Dolphin, is a small but recognizable constellation in the northern celestial hemisphere. Its distinctive shape resembles a leaping dolphin, making it a charming sight in the night sky.  It is one of the 48 constellations listed by Ptolemy, and one of the 88 modern constellations recognized by the International Astronomical Union (IAU).
  • 1.7K
  • 08 Mar 2024
Topic Review
Norma
Norma, Latin for "the square," is a small southern constellation located in the Milky Way. Despite its diminutive size and lack of bright stars, it remains one of the 88 modern constellations recognized by the International Astronomical Union (IAU).
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  • 15 Mar 2024
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.
  • 1.7K
  • 28 Oct 2022
Topic Review
Vallis (Planetary Geology)
Vallis or valles /ˈvælɪs/ (plural valles /ˈvæliːz/) is the Latin word for valley. It is used in planetary geology to name landform features on other planets. Scientists used vallis for old river valleys they discovered when they sent the first probes to Mars. The Viking Orbiters caused a revolution in our ideas about water on Mars; finding huge river valleys in many areas. Space craft cameras showed that floods of water broke through dams, carved deep valleys, eroded grooves into bedrock, and traveled thousands of kilometers. Some valles on Mars (Mangala Vallis, Athabasca Vallis, Granicus Vallis, and Tinjar Valles) clearly begin at graben. On the other hand, some of the large outflow channels begin in rubble-filled low areas, called chaos or chaotic terrain. It has been suggested that massive amounts of water were trapped under pressure beneath a thick cryosphere (layer of frozen ground), then the water was suddenly released, perhaps when the cryosphere was broken by a fault.
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  • 23 Nov 2022
Topic Review
Caelum
Caelum, recognized by the International Astronomical Union (IAU), is a faint and small constellation in the southern celestial hemisphere. It was introduced by the French astronomer Nicolas Louis de Lacaille in the 18th century, representing a chisel, part of the sculptor's tools, in his constellation sketches.
  • 1.6K
  • 29 Feb 2024
Topic Review
International Space Station Program
The International Space Station program is tied together by a complex set of legal, political and financial agreements between the fifteen nations involved in the project, governing ownership of the various components, rights to crewing and utilization, and responsibilities for crew rotation and resupply of the International Space Station. These agreements tie together the five space agencies and their respective International Space Station programs and govern how they interact with each other on a daily basis to maintain station operations, from traffic control of spacecraft to and from the station, to utilization of space and crew time. In March 2010, the International Space Station Program Managers from each of the five partner agencies were presented with Aviation Week's Laureate Award in the Space category, and NASA's International Space Station Program was awarded the 2009 Collier Trophy.
  • 1.6K
  • 10 Nov 2022
Topic Review
Advanced Technology Large-Aperture Space Telescope
The Advanced Technology Large-Aperture Space Telescope (ATLAST) is an 8– to 16.8–meter UV-optical-NIR space telescope proposed by the Space Telescope Science Institute (STScI), the science operations center for the Hubble Space Telescope (HST). If launched, ATLAST would be a replacement and successor for the HST, with the ability to obtain spectroscopic and imaging observations of astronomical objects in the ultraviolet, optical, and infrared wavelengths, but with substantially better resolution than either HST or the planned James Webb Space Telescope (JWST). Like JWST, ATLAST would be launched to the Sun-Earth L2 Lagrange point. ATLAST is envisioned as a flagship mission of the 2025–2035 period, designed to determine whether there is life elsewhere in the galaxy. It would attempt to accomplish this by searching for "biosignatures" (such as molecular oxygen, ozone, water, and methane) in the spectra of terrestrial exoplanets. The backronym that the project currently uses, 'ATLAST', is in fact a pun. It refers to the time taken to decide on a true, visible-light, successor for the Hubble Space Telescope. However, it is expected that, as the project progresses, a new name would be chosen for the mission.
  • 1.6K
  • 25 Oct 2022
Biography
Yuri N. Gnedin
Prof. Dr. Yuri N. Gnedin was an outstanding astrophysicist whose scientific interests and expertise were extraordinarily wide. He was an expert in theoretical investigation of the polarized radiation transfer, generation of high-energy radiation in close binary star systems and galactic nuclei, and cyclotron lines in spectra of accreting neutron stars. Prof. Dr. Yuri N. Gnedin developed the pion
  • 1.6K
  • 20 Dec 2022
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