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Topic Review
Pegasus
Pegasus, the winged horse of Greek mythology, is a prominent constellation in the northern sky, known for its distinctive "Great Square" asterism. As one of the 48 constellations cataloged by the ancient Greek astronomer Ptolemy, Pegasus has a rich cultural and astronomical significance. Its association with the mythical creature Pegasus, ridden by heroes such as Perseus and Bellerophon, adds to its allure and makes it a captivating subject for stargazers.
  • 630
  • 15 Mar 2024
Topic Review
Carina
Carina, Latin for "the keel" or "the hull," is a constellation in the southern celestial hemisphere. Representing the keel of the mythical ship Argo Navis, Carina is home to several notable celestial objects, including the second-brightest star in the night sky, Canopus. It is rich in nebulae, star clusters, and other deep-sky wonders.
  • 625
  • 29 Feb 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.
  • 613
  • 05 Dec 2022
Topic Review
The Macro-Physics of the Quark-Nova
A quark-nova is a hypothetical stellar evolution branch where a neutron star converts explosively into a quark star. Due to the high peak neutrino luminosities, neutrino pair annihilation can deposit as much as 1052 ergs in kinetic energy in the matter overlaying the neutrinosphere, yielding relativistic quark-nova ejecta. 
  • 612
  • 28 Jun 2022
Topic Review
List of Delta IV Medium Launches
Since November 2002, rockets from the Delta 4 Medium family have been launched 29 times, all of which were successful. Its last flight was with a 3rd generation GPS satellite in August 2019.
  • 612
  • 18 Oct 2022
Topic Review
Current Status of The Celestial Reference Frame
The International Celestial Reference Frame (ICRF) is based on the currently accepted International Celestial Reference System (ICRS) and forms the basis for all positional astronomy in the radio domain. The first three generations of this frame have been built from high precision Very Long Baseline Interferometry (VLBI) astrometric measurements of positions of extragalactic radio sources (quasars and other radio-loud Active Galactic Nuclei, AGN), with each successive realization of the ICRF becoming more precise. VLBI angular position accuracy has now improved to near the 100 micro-arcsecond (μas) level. Catalogues of positions of extragalactic radio sources with the highest precision, such as the ICRF, are crucial to many applications, such as determining the Earth’s orientation in space, providing calibrator sources for astronomy, studying the motion of tectonic plates, and in spacecraft navigation. The ICRF also contributes towards the realization of a Global Geodetic Reference Frame (GGRF) for sustainable development, a resolution adopted by the United Nations in 2015.
  • 598
  • 28 Jul 2022
Topic Review
Leo
Leo, the Lion, is one of the zodiac constellations, known for its distinctive shape resembling a lion's mane and head. It is one of the oldest recognized constellations, dating back to ancient civilizations such as the Mesopotamians, Egyptians, and Greeks. Leo is home to several bright stars and notable deep-sky objects.
  • 582
  • 15 Mar 2024
Topic Review
GEO600
GEO600 is a gravitational wave detector located near Sarstedt in the South of Hanover, Germany. It is designed and operated by scientists from the Max Planck Institute for Gravitational Physics, Max Planck Institute of Quantum Optics and the Leibniz Universität Hannover, along with University of Glasgow, University of Birmingham and Cardiff University in the United Kingdom, and is funded by the Max Planck Society and the Science and Technology Facilities Council (STFC). GEO600 is part of a worldwide network of gravitational wave detectors. This instrument, and its sister interferometric detectors, when operational, are some of the most sensitive gravitational wave detectors ever designed. They are designed to detect relative changes in distance of the order of 10−21, about the size of a single atom compared to the distance from the Sun to the Earth. GEO600 is capable of detecting gravitational waves in the frequency range 50 Hz to 1.5 kHz. Construction on the project began in 1995.
  • 577
  • 03 Nov 2022
Topic Review
Soyuz TMA-20
Soyuz TMA-20 was a human spaceflight to the International Space Station (ISS) and was part of the Soyuz programme. It lifted off from the Baikonur Cosmodrome in Kazakhstan on December 15, 2010, and docked with the ISS two days later. The three-person crew of Soyuz TMA-20 – Dmitri Kondratyev, Catherine Coleman and Paolo Nespoli – represented the ISS partner organizations of Roscosmos, NASA and the European Space Agency (ESA). Soyuz TMA-20's crew represented half of the members of Expedition 27; the other three members of the expedition arrived at the station on board Soyuz TMA-21 on April 6, 2011. The COSPAR ID of Soyuz TMA-20 was 2010-067A. It is ISS flight 25S. On May 24, 2011, after spending 159 days in space, the Soyuz TMA-20 descent module landed safely in Zhezkazgan, Kazakhstan, carrying Kondratyev, Coleman and Nespoli.
  • 577
  • 17 Nov 2022
Topic Review
Soyuz T-15
Soyuz T-15 (Russian: Союз T-15, Union T-15) was a crewed mission to the Mir and Salyut 7 space stations and was part of the Soyuz programme. It marked the final flight of the Soyuz-T spacecraft, the third generation Soyuz spacecraft, which had been in service for seven years from 1979 to 1986. This mission marked the first time that a spacecraft visited, and docked with, two space stations in the same mission.
  • 575
  • 17 Oct 2022
Topic Review
Cygnus
Cygnus, known as the Swan, is a prominent constellation in the northern celestial hemisphere. Its distinctive shape resembles a flying bird with outstretched wings, earning it the nickname "the Northern Cross." Cygnus is rich in celestial wonders, including the famous binary star system Albireo, the North America Nebula, and the Veil Nebula complex.
  • 568
  • 08 Mar 2024
Topic Review
Testing General Relativity with Gravitational Waves
The detections of gravitational-wave (GW) signals from compact binary coalescence by ground-based detectors have opened up the era of GW astronomy. These observations provide opportunities to test Einstein’s general theory of relativity at the strong-field regime. 
  • 565
  • 18 Jan 2022
Topic Review
Centaurus
Centaurus, a prominent southern hemisphere constellation, is one of the largest and most recognizable constellations in the night sky. Named after the centaur Chiron from Greek mythology, Centaurus features the bright Alpha Centauri system, one of the closest star systems to Earth.
  • 565
  • 29 Feb 2024
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".
  • 564
  • 15 Mar 2024
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. 
  • 563
  • 15 Mar 2024
Biography
Yury Romanenko
Yury Viktorovich Romanenko (Russian: Ю́рий Ви́кторович Романе́нко, Jurij Viktorovič Romanenko; born August 1, 1944) is a former Soviet cosmonaut, twice Hero of the Soviet Union (March 16, 1978 and September 26, 1980). Over his career, Yury Romanenko spent a total of 430 days 20 hours 21 minutes 30 seconds in space and 18 hours in space walks.[1] In 1987 he was a reside
  • 546
  • 07 Dec 2022
Topic Review
Odd Radio Circles and Their Environment
Odd Radio Circles (ORCs) are unexpected faint circles of diffuse radio emission discovered in recent wide deep radio surveys. They are typically about one arcmin in diameter, and may be spherical shells of synchrotron emission about a million light years in diameter, surrounding galaxies at a redshift of ∼0.2–0.6. Here we study the properties and environment of the known ORCs.
  • 543
  • 17 Nov 2021
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.
  • 542
  • 06 Oct 2022
Topic Review
PSR J1614–2230
PSR J1614–2230 is a neutron star in a binary system with a white dwarf. It was discovered in 2006 with the Parkes telescope in a survey of unidentified gamma ray sources in the Energetic Gamma Ray Experiment Telescope catalog. PSR J1614–2230 is a millisecond pulsar, a type of neutron star, that spins on its axis roughly 317 times per second, corresponding to a period of 3.15 milliseconds. Like all pulsars, it emits radiation in a beam, similar to a lighthouse. Emission from PSR J1614–2230 is observed as pulses at the spin period of PSR J1614–2230. The pulsed nature of its emission allows for the arrival of individual pulses to be timed. By measuring the arrival time of pulses, astronomers observed the delay of pulse arrivals from PSR J1614–2230 when it was passing behind its companion from the vantage point of Earth. By measuring this delay, known as the Shapiro delay, astronomers determined the mass of PSR J1614–2230 and its companion. The team performing the observations found that the mass of PSR J1614–2230 is 1.97 ± 0.04 M☉. This mass made PSR J1614–2230 the most massive known neutron star at the time of discovery, and rules out many neutron star equations of state that include exotic matter such as hyperons and kaon condensates. In 2013, a slightly higher neutron star mass measurement was announced for PSR J0348+0432, 2.01 ± 0.04 M☉. This confirmed the existence of such massive neutron stars using a different measuring technique.
  • 541
  • 04 Nov 2022
Topic Review
List of 19th-Century Lunar Eclipses
See also: List of lunar eclipses, List of 18th-century lunar eclipses, and List of 20th-century lunar eclipses
  • 539
  • 25 Oct 2022
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