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Topic Review
Monoceros
Monoceros, Latin for "unicorn," is a constellation located in the celestial equator. Despite lacking ancient mythological roots, it was introduced in the 17th century by the astronomer Jakob Bartsch and later included in Johann Bayer's Uranometria, symbolizing the unicorn, a creature of myth and fantasy.
  • 812
  • 15 Mar 2024
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.
  • 811
  • 25 Oct 2022
Topic Review
Canis Major
Canis Major, Latin for "Greater Dog," is one of the most prominent constellations in the southern celestial hemisphere. Often depicted as one of Orion's hunting dogs in Greek mythology, Canis Major is best known for its brightest star, Sirius, also called the Dog Star, which is the brightest star in the night sky. With its distinctive shape and rich cultural significance, Canis Major has fascinated astronomers and storytellers throughout history.
  • 803
  • 29 Feb 2024
Topic Review
Virgo
Virgo is one of the 12 constellations of the zodiac, located between Leo to the west and Libra to the east. Covering a vast area of the sky, Virgo is the second-largest constellation after Hydra. Represented as a maiden holding a sheaf of wheat, Virgo is often associated with fertility and agriculture in ancient mythology. This constellation is notable for hosting the bright star Spica, which serves as a celestial marker for navigation and observation.
  • 801
  • 15 Mar 2024
Topic Review
The Andromeda Galaxy
Star formation histories of galaxies are critically important for understanding the process of galaxy formation and the structure and contents of galaxies. Star formation can and has been studied in local galaxies for which the stellar populations are resolved and in more distant galaxies for which stars are unresolved, which are instead modeled as populations. Structural components of a galaxy can be resolved at much larger distances. The structural components include those long recognized, such as bulge, disk and halo. More recently recognized structures include separation of disks into thin and thick disk components and stellar streams, as well as recognition of significant numbers of dwarf companion galaxies. Stellar streams are the most recently recognized components of galaxies, mainly using observations of the Milky Way and the Andromeda Galaxy (M31).
  • 796
  • 14 Aug 2023
Topic Review
Ursa Major
Ursa Major, often referred to as the Great Bear, is one of the most recognizable and prominent constellations in the northern celestial hemisphere. Its distinctive shape, resembling a large bear with a long tail, has captivated human imagination for millennia. At the heart of Ursa Major lies the Big Dipper, a prominent asterism formed by seven bright stars that serve as a navigational guide and cultural icon across cultures and civilizations.
  • 781
  • 15 Mar 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.
  • 773
  • 10 Nov 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.
  • 773
  • 11 Nov 2022
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.
  • 767
  • 15 Mar 2024
Topic Review
The Crab Nebula in Gamma-Rays
The Crab nebula is one of the best studied objects in the sky, second only to the Sun. It is the remnant of a supernova explosion occurred in A. D. 1054, and it represents the prototype of an entire class of supernova remnants: Pulsar Wind Nebulae. It consists of two different bright non-thermal sources — the pulsar and the nebula. Both objects have played a key role in the development of high-energy astrophysics. Thanks to their bright emission at all wavelengths, they have been observed by virtually all new astronomical instruments and have been at the origin of a wealth of important scientific discoveries.
  • 766
  • 13 Jan 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.
  • 764
  • 05 Dec 2022
Topic Review
Perturbation
In astronomy, perturbation is the complex motion of a massive body subjected to forces other than the gravitational attraction of a single other massive body. The other forces can include a third (fourth, fifth, etc.) body, resistance, as from an atmosphere, and the off-center attraction of an oblate or otherwise misshapen body.
  • 763
  • 28 Oct 2022
Topic Review
Lyra
Lyra is a constellation in the northern celestial hemisphere known for its prominent star Vega, one of the brightest stars in the sky. Represented as a lyre, a musical instrument from Greek mythology, Lyra is rich in celestial objects. Lyra is bordered by Vulpecula to the south, Hercules to the west, Draco to the north, and Cygnus to the east.
  • 756
  • 15 Mar 2024
Topic Review
MOST (Satellite)
The Microvariability and Oscillations of Stars telescope, better known simply as MOST, was Canada 's first space telescope. Up until nearly 10 years after its launch it was also the smallest space telescope in orbit (for which its creators nicknamed it the "Humble Space Telescope", in reference to one of the largest, the Hubble). MOST was the first spacecraft dedicated to the study of asteroseismology, subsequently followed by the now-completed CoRoT and Kepler missions. It was also the first Canadian science satellite launched since ISIS II, 32 years previously.
  • 754
  • 02 Nov 2022
Topic Review
AIDA (Mission)
The Asteroid Impact and Deflection Assessment (AIDA) mission is a proposed pair of space probes which will study and demonstrate the kinetic effects of crashing an impactor spacecraft into an asteroid moon. The mission is intended to test and validate impact models of whether a spacecraft could successfully deflect an asteroid on a collision course with Earth. The original plan called for a European spacecraft, the Asteroid Impact Mission (AIM), to operate in synergy with a large NASA impactor called Double Asteroid Redirection Test (DART) and observe the immediate effects of the impact. AIM was cancelled in 2016 when Germany was unable to fund its portion, and after some backlash within ESA, AIM was replaced in 2018 with a smaller spacecraft called Hera that will launch five years after DART to orbit and study the crater on the asteroid. Hera will also deploy Europe's first CubeSats in deep space for close-up asteroid surveying: Juventas and Milani. DART is currently planned to impact in 2022 in the small moon of asteroid 65803 Didymos, while Hera will arrive at Didymos in 2027, five years after DART's impact.
  • 742
  • 01 Nov 2022
Topic Review
Exploration Mission-1
Exploration Mission-1 or EM-1 (previously known as Space Launch System 1 or SLS-1) is the uncrewed first planned flight of the Space Launch System and the second flight of the Orion Multi-Purpose Crew Vehicle. The launch is planned for June 2020 from Launch Complex 39B at the Kennedy Space Center. The Orion spacecraft will spend approximately 3 weeks in space, including 6 days in a retrograde orbit around the Moon. It is planned to be followed by Exploration Mission 2 in 2023.
  • 734
  • 28 Sep 2022
Topic Review
Cetus
Cetus, known as the Whale, is a large constellation visible in the southern sky. In Greek mythology, Cetus represents the sea monster sent by Poseidon to terrorize the kingdom of Aethiopia, eventually slain by Perseus to rescue Andromeda. As one of the 88 recognized constellations, Cetus holds a special place in the realm of astronomy and mythology. 
  • 713
  • 08 Mar 2024
Topic Review
Cosmology Can Serve to Determine Neutrino's Properties
Neutrino particles have been found, due to their non-interacting, almost-vanishing mass, and relativistic nature, as being suitable to hold roles in many phenomena in nature, which have made them attract a large interest among the scientific community. In particular, on the cosmological level, the neutrino is one of the few components whose contribution to the Universe energy budget changes with its expansion, from being part of the radiation to that of the matter density, with implications on the expansion of the background or the growth of large-scale structures. It has also the feature of being abundantly present since the Universe’s early beginning, participating by then to the different phases of its evolution, which allows us to constrain its main properties such as its mass and number of species by any of the known cosmological observables.
  • 711
  • 27 May 2022
Topic Review
Scorpius
Scorpius, known as "the Scorpion," is a striking constellation visible in the southern celestial hemisphere during the summer months. With its distinctive shape resembling a scorpion's curved tail, Scorpius is one of the most recognizable constellations in the night sky. 
  • 710
  • 15 Mar 2024
Topic Review
Sagittarius
Sagittarius, often referred to as "the Archer," is a prominent constellation in the southern celestial hemisphere, renowned for its association with Greek mythology and the mythical centaur Chiron. Positioned along the Milky Way, Sagittarius hosts a wealth of celestial wonders, including the galactic center and numerous star clusters.
  • 710
  • 15 Mar 2024
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