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Topic Review
Ara
Ara is a constellation in the southern celestial hemisphere. The name "Ara" originates from Greek mythology, where it represents the altar used by the gods in their divine ceremonies.
  • 1.6K
  • 29 Feb 2024
Topic Review
Stellar Constellations in Fiction
Some stellar constellations have been featured in fictional works.
  • 1.6K
  • 31 Oct 2022
Topic Review
Leo Minor
Leo Minor, the Lesser Lion, is a small constellation located in the northern celestial hemisphere. Its name is Latin for "the smaller lion", in contrast to Leo, the larger lion. It lies between the larger and more recognizable Ursa Major to the north and Leo to the south. 
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  • 15 Mar 2024
Topic Review
Mars Helicopter Ingenuity
Ingenuity (also known as the Mars Helicopter) is a robotic helicopter that is planned to be used to test the technology to scout interesting targets on Mars, and help plan the best driving route for future Mars rovers. The small drone helicopter is planned for deployment in 2021 from the Perseverance rover as part of the Mars 2020 mission. It is expected to fly up to five times during its 30-day test campaign, early in the rover's mission, as it is primarily a technology demonstration. Each flight is planned to take no more than three minutes, at altitudes ranging from 3 to 10 m above the ground. It could potentially cover a distance of up to 300 metres (980 ft) per flight. It can use autonomous control and communicate with the Perseverance rover directly after each landing. If it works as expected, NASA could build on the design for future Mars aerial missions. MiMi Aung is the project lead. Other contributors include AeroVironment Inc., NASA Ames Research Center, and NASA Langley Research Center.
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  • 01 Dec 2022
Topic Review
Canes Venatici
Canes Venatici, Latin for "hunting dogs," is a small northern constellation situated between Ursa Major and Boötes. It was introduced by Johannes Hevelius in the 17th century, representing the hunting dogs of Boötes, the Herdsman. The constellation is notable for hosting several interesting celestial objects, including the famous Whirlpool Galaxy (M51) and the Sunflower Galaxy (M63).
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  • 29 Feb 2024
Topic Review
CFBDSIR 1458+10
CFBDSIR J145829+101343 (Coordinates: 14h 58m 29.0s, +10° 13′ 43″, designation abbreviated to CFBDSIR 1458+10, or CFBDSIR J1458+1013) is a binary system of two brown dwarfs of spectral classes T9 + Y0 orbiting each other, located in constellation Boötes about 104 light-years away from Earth. The smaller companion, CFBDSIR 1458+10B, has a surface temperature of approx 370 K (≈100 °C) and used to be known as the coolest known brown dwarf until the discovery of WISE 1828+2650 in August 2011.
  • 1.6K
  • 09 Oct 2022
Topic Review
Pavo
Pavo, Latin for "peacock," is a small but distinct constellation in the southern sky. Representing the majestic bird from ancient mythology, Pavo is notable for its compact arrangement of stars and its proximity to the south celestial pole, making it a prominent feature of the southern hemisphere's night sky.
  • 1.6K
  • 15 Mar 2024
Topic Review
Brite-Constellation
BRITE-Constellation is devoted to high-precision optical photometric monitoring of bright stars, distributed all over the Milky Way, in red and/or blue passbands. Photometry from space avoids the turbulent and absorbing terrestrial atmosphere and allows for very long and continuous observing runs with high time resolution and thus provides the data necessary for understanding various processes inside stars (e.g., asteroseismology) and in their immediate environment. 
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  • 15 Jul 2021
Topic Review
Origin of ICL
Not all the light in galaxy groups and clusters comes from stars that are bound to galaxies. A significant fraction of it constitutes the so-called intracluster or diffuse light (ICL), a low surface brightness component of groups/clusters generally found in the surroundings of the brightest cluster galaxies and intermediate/massive satellites
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  • 13 Sep 2021
Topic Review
Cosmic-ray Sources - Black Holes
Cosmic rays were discovered over one hundred years ago but there are still unsolved problems. One of the hot problems is the origin of cosmic rays of the highest energies. Sources are still unclear and it is neither clear how particles gain ultra-high energies. Possible sources of cosmic rays at the highest energies are supermassive black holes. From this perspective we discuss in a popular form some recent developments in cosmic ray studies along with author’s recent results.The paper also offers materials for further reading.
  • 1.5K
  • 21 Jan 2021
Topic Review
Timeline of Telescope Technology
The following timeline lists the significant events in the invention and development of the telescope.
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  • 18 Nov 2022
Topic Review
Lupus
Lupus, the Latin word for "wolf," is a constellation located in the southern celestial hemisphere. Representing a wolf, it was one of the 48 constellations listed by Ptolemy, and is one of the 88 modern constellations recognized by the International Astronomical Union.
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  • 15 Mar 2024
Topic Review
Horologium
Horologium, Latin for "clock" or "timepiece," is a faint constellation located in the southern celestial hemisphere. It was first described by the French astronomer Nicolas-Louis de Lacaille in 1756.
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  • 15 Mar 2024
Topic Review
Crater
Crater, Latin for "cup" or "bowl," is a small and inconspicuous constellation located in the southern celestial hemisphere. Positioned near the prominent constellation Hydra, Crater represents a celestial cup often associated with the mythological story of the Greek god Apollo and his daily ritual of sun-chariot driving.
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  • 08 Mar 2024
Topic Review
Near-Earth Object Surveillance Mission
The Near-Earth Object Surveillance Mission (NEOSM), formerly called Near-Earth Object Camera (NEOCam) is a planned space-based infrared telescope designed to survey the Solar System for potentially hazardous asteroids. The NEO Surveillance Mission will be carried out by the NEO Surveyor spacecraft, which will survey from the Sun–Earth L1 (inner) Lagrange point, allowing it to look close to the Sun and see objects inside Earth's orbit. The mission will be a successor to the NEOWISE mission; the principal investigator is also NEOWISE's principal investigator, Amy Mainzer at the University of Arizona. Since first proposed in 2006, the concept unsuccessfully competed repeatedly for NASA funding against science missions unrelated to planetary defense, despite a 2005 US Congressional directive to NASA. In 2019, it was decided to implement this mission by the Planetary Defense Coordination Office since it is a public safety issue. The Jet Propulsion Laboratory will lead development of the mission.
  • 1.5K
  • 05 Dec 2022
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.
  • 1.5K
  • 15 Oct 2023
Topic Review
List of Exoplanetary Host Stars
The following is a list of exoplanetary host stars. The table contains information about the coordinates, spectral and physical properties, and number of confirmed planets. The two most important stellar properties are mass and metallicity because they determine how these planetary systems form. Stars of higher mass and metallicity tend to have more numerous and more massive planets. Most of the stars below are solar-type, mainly in the spectral classes F, G, and K, because astronomers tend to look for planets around stars similar to the Sun. Others are giants, which have used up all the hydrogen in their cores. Finding planets around giant stars gives clues as to how planetary systems evolve and how the properties of planets change with the evolution of the stars. As of April 2018, there are 2,816 stars with at least one confirmed planet, of which 628 stars have two or more confirmed planets; that is, 22% of all confirmed exoplanetary host stars have two or more confirmed planets. As of 2018, the star with the most confirmed planets is Kepler-90, with eight planets, although HD 10180 may have nine (two are unconfirmed). The most massive exoplanetary host star is Omicron Ursae Majoris (3.09 M☉), while the least massive is 2M J044144 (0.021 M☉). The most metal-rich star is NN Serpentis (1.744, 55.5 × Sun), while the most metal-poor is BD+20°2457 (−0.999, 0.100 × Sun). The nearest exoplanetary host star is Proxima Centauri (4.25 ly), while the most distant is NY Virginis (26940 ly). Visually, the brightest exoplanetary host star seen from Earth is Pollux (1.15), while the faintest is OGLE-2005-BLG-390L (27.98).
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  • 04 Oct 2022
Topic Review
Primary Life Support System
A Primary (or Portable or Personal) Life Support System (or Subsystem) (PLSS), is a device connected to an astronaut or cosmonaut's spacesuit, which allows extra-vehicular activity with maximum freedom, independent of a spacecraft's life support system. The PLSS is generally worn like a backpack. The functions performed by the PLSS include: The air handling function of a PLSS is similar to that of a diving rebreather, in that exhaled gases are recycled into the breathing gas in a closed loop. When used in a microgravity environment, a separate propulsion system is generally needed for safety and control, since there is no physical connection to a spacecraft.
  • 1.5K
  • 11 Nov 2022
Topic Review
Satellite System
A satellite system is a set of gravitationally bound objects in orbit around a planetary mass object (incl. sub-brown dwarfs and rogue planets) or minor planet, or its barycenter. Generally speaking, it is a set of natural satellites (moons), although such systems may also consist of bodies such as circumplanetary disks, ring systems, moonlets, minor-planet moons and artificial satellites any of which may themselves have satellite systems of their own (see Subsatellites). Some bodies also possess quasi-satellites that have orbits gravitationally influenced by their primary, but are generally not considered to be part of a satellite system. Satellite systems can have complex interactions including magnetic, tidal, atmospheric and orbital interactions such as orbital resonances and libration. Individually major satellite objects are designated in Roman numerals. Satellite systems are referred to either by the possessive adjectives of their primary (e.g. "Jovian system"), or less commonly by the name of their primary (e.g. "Jupiter system"). Where only one satellite is known, or it is a binary with a common centre of gravity, it may be referred to using the hyphenated names of the primary and major satellite (e.g. the "Earth-Moon system"). Many Solar System objects are known to possess satellite systems, though their origin is still unclear. Notable examples include the largest satellite system, the Jovian system, with 80 known moons (including the large Galilean moons) and the Saturnian System with 83 known moons (and the most visible ring system in the Solar System). Both satellite systems are large and diverse. In fact all of the giant planets of the Solar System possess large satellite systems as well as planetary rings, and it is inferred that this is a general pattern. Several objects farther from the Sun also have satellite systems consisting of multiple moons, including the complex Plutonian system where multiple objects orbit a common center of mass, as well as many asteroids and plutinos. Apart from the Earth-Moon system and Mars' system of two tiny natural satellites, the other terrestrial planets are generally not considered satellite systems, although some have been orbited by artificial satellites originating from Earth. Little is known of satellite systems beyond the Solar System, although it is inferred that natural satellites are common. J1407b is an example of an extrasolar satellite system. It is also theorised that Rogue planets ejected from their planetary system could retain a system of satellites.
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  • 25 Oct 2022
Topic Review
Soyuz TMA-03M
Soyuz TMA-03M was a spaceflight to the International Space Station (ISS). It launched on 21 December 2011 from Site One at the Baikonur Cosmodrome, Kazakhstan, carrying three members of Expedition 30 to the ISS. TMA-03M was the 112th flight of a Russian Soyuz spacecraft, since the first in 1967, and the third flight of the modernised Soyuz-TMA-M version. The docking with the International Space Station took place at 19:19 Moscow Time on 23 December, three minutes ahead of schedule. The crew were Oleg Kononenko (Russia , commander), André Kuipers (the Netherlands) and Donald Pettit (United States ). The Soyuz remained aboard the space station for the Expedition 30 increment to serve as an emergency escape vehicle if needed. The capsule used in the mission can be seen at the Space Expo visitors center at the European Space Research and Technology Centre in Noordwijk, Netherlands.
  • 1.5K
  • 05 Dec 2022
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