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Topic Review
«Hadron-M» Complex Installation
“Hadron-M complex installation”, which included an ionization-neutron calorimeter with an area of 55 m2 and an absorber thickness of 1244 g/cm2 (out of eight rows of ionization chambers), one row of neutron detectors and two shower systems of scintillation detectors. The effective area of the “Hadron-M” complex installation was about 30,000 m2.
  • 605
  • 27 Feb 2023
Topic Review
(225088) 2007 OR10
(225088) 2007 OR10, proposed to be named Gonggong, is a likely dwarf planet in the Solar System beyond Neptune, and is a member of the scattered disc. It has a highly eccentric and inclined orbit during which it ranges from 33–101 astronomical units (4.9–15.1 billion kilometers) from the Sun. (As of 2019), its distance from the Sun is 88 AU (1.32×1010 km; 8.2×109 mi), and it is the sixth-farthest known Solar System object. 2007 OR10 is in a 3:10 orbital resonance with Neptune, in which it completes three orbits around the Sun for every ten orbits completed by Neptune. 2007 OR10 was discovered in July 2007 by American astronomers Megan Schwamb, Michael Brown, and David Rabinowitz at the Palomar Observatory, and the discovery was announced in January 2009. At 1,230 km (760 mi) in diameter, 2007 OR10 is approximately the size of Pluto's moon Charon, and is the fifth-largest known trans-Neptunian object in the Solar System. It is sufficiently massive to be gravitationally rounded, thereby qualifying for dwarf planet status. Its large mass also makes retention of a tenuous atmosphere of methane just possible, though such an atmosphere would slowly escape into space. 2007 OR10 is currently the largest known body in the Solar System without an official name, but in 2019, the discoverers hosted an online poll for the general public to help choose a name for the object, and the name Gonggong won. The winning name is derived from Gonggong, a Chinese water god responsible for chaos, floods and the tilt of the Earth. 2007 OR10 is red in color, likely due to the presence of organic compounds called tholins on its surface. Water ice is also present on its surface, which hints at a brief period of cryovolcanic activity in the distant past. 2007 OR10 rotates slowly compared to other trans-Neptunian objects, which typically have rotation periods less than 12 hours, which may be due to its natural satellite, provisionally designated S/2010 (225088) 1.
  • 1.2K
  • 02 Dec 2022
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.
  • 859
  • 03 Nov 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.
  • 498
  • 21 Oct 2022
Topic Review
(6545) 1986 TR6
(6545) 1986 TR6, provisional designation 1986 TR6, is a Jupiter trojan from the Greek camp, approximately 53 kilometers (33 miles) in diameter. It was discovered on 5 October 1986, by Slovak astronomer Milan Antal at the Piwnice Astronomical Observatory in Poland. The dark D-type asteroid has a rotation period of 16.3 hours and belongs to the 90 largest Jupiter trojans. It has not been named since its numbering in September 1995.
  • 271
  • 09 Nov 2022
Topic Review
1769 Transit of Venus Observed from Tahiti
On June 3, 1769, British navigator Captain James Cook, British naturalist Joseph Banks, British astronomer Charles Green and Swedish naturalist Daniel Solander recorded the transit of Venus on the island of Tahiti during Cook's first voyage around the world. During a transit, Venus appears as a small black disc travelling across the Sun. This unusual astronomical phenomenon takes place in a pattern that repeats itself every 243 years. It includes two transits that are eight years apart, separated by breaks of 121.5 and 105.5 years. These men, along with a crew of scientists, were commissioned by the Royal Society of London for the primary purpose of viewing the transit of Venus. Not only would their findings help expand scientific knowledge, it would help with navigation by accurately calculating the observer's longitude. At this time, longitude was difficult to determine and not always precise. A "secret" mission that followed the transit included the exploration of the South Pacific to find the legendary Terra Australis Incognita or "unknown land of the South."
  • 1.0K
  • 30 Sep 2022
Topic Review
2020 AV2
2020 AV2 is a 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 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 around 16.4, the asteroid is expected to be larger than 1 km in diameter.
  • 338
  • 25 Nov 2022
Topic Review
2020 XL5
2020 XL5 is a near-Earth asteroid and Earth trojan discovered by the Pan-STARRS 1 survey at Haleakala Observatory, Hawaii on 12 December 2020. It oscillates around the Sun–Earth L4 Lagrangian point (leading 60°), one of the dynamically stable locations where the combined gravitational force acts through the Sun's and Earth's barycenter. Analysis of 2020 XL5's trojan orbit stability suggests it will remain around Earth's L4 point for at least four thousand years until gravitational perturbations from repeated close encounters with Venus destabilize its trojan configuration. With a diameter about 1.2 km (0.75 mi), 2020 XL5 is the second Earth trojan discovered and is the largest of its kind known, after 2010 TK7.
  • 720
  • 18 Oct 2022
Topic Review
88 Modern Constellations
In contemporary astronomy, the sky is divided into 88 regions called constellations, generally based on the asterisms (which are also called "constellations") of Greek and Roman mythology. The number of 88, along with the contemporary scientific notion of "constellation", was conventioned in 1922 by the International Astronomical Union in order to establish a universal pattern for professional astronomers, who defined constellations from then on as regions of the sky separated by arcs of right ascensions and declinations and grouped by asterisms of their historically most important stars, which cover the entire celestial sphere. The constellations along the ecliptic are called the zodiac. The ancient Sumerians, and later the Greeks (as recorded by Ptolemy), established most of the northern constellations in international use today. When explorers mapped the stars of the southern skies, European and American astronomers proposed new constellations for that region, as well as ones to fill gaps between the traditional constellations. Not all of these proposals caught on, but in 1922, the International Astronomical Union (IAU) adopted the modern list of 88 constellations. After this, Eugène Joseph Delporte drew up precise boundaries for each constellation, so that every point in the sky belonged to exactly one constellation.
  • 1.2K
  • 08 Oct 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.
  • 865
  • 25 Oct 2022
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