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Cool Companions On Ultrawide Orbits
The COol Companions ON Ultrawide orbiTS (COCONUTS) program is a large-scale survey for wide-orbit planetary and substellar companions considered the first survey of this type of celestial bodies. In 2021, the team announced COCONUTS-2b, the closest exoplanet directly imaged ever. The program is a dedicated large-scale search for wide-orbit giant planets and brown dwarf companions, targeting a sample of 300,000 stars. By using multi-wavelength Photometry (astronomy), photometry and multi-epoch astrometry, astronomers are able to assess the candidates' companionship and ultracool nature. List of discoveries See also * List of exoplanet search projects References {{Reflist Exoplanet search projects ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
COCONUTS-2b
COCONUTS-2 b, or WISEPA J075108.79-763449.6, is a gas giant exoplanet that orbits the M-type star L 34-26. With a mass of 6.3 Jupiter mass, Jupiters, it takes over one million years to complete one orbit around the star, and it is 6000 Astronomical units, AU away from it. The planet was discovered in 2011 and was initially identified as a T9 free-floating brown dwarf WISEPA J075108.79−763449.6. During the Cool Companions on Ultrawide Orbits, COol Companions ON Ultrawide orbiTS (COCONUTS) survey, its association with L 34-26 was announced in 2021. At a distance of 10.9 pc, COCONUTS-2b is the closest direct imaging, directly imaged exoplanet to Earth known to date. The researchers found that it is unlikely that COCONUTS-2b was formed inside the protoplanetary disk of the host star and it is more likely that the planet formed on its own via high entropy formation (aka hot-start process). Atmosphere The planet has a spectral type of T9, based on a low Signal-to-noise ratio, sign ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exoplanet
An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917 but was not recognized as such. The first confirmation of detection occurred in 1992. A different planet, initially detected in 1988, was confirmed in 2003. There are many methods of detecting exoplanets. Transit photometry and Doppler spectroscopy have found the most, but these methods suffer from a clear observational bias favoring the detection of planets near the star; thus, 85% of the exoplanets detected are inside the tidal locking zone. In several cases, multiple planets have been observed around a star. About 1 in 5 Sun-like starsFor the purpose of this 1 in 5 statistic, "Sun-like" means G-type star. Data for Sun-like stars was not available so this statistic is an extrapolation from data about K-type stars. have an "Earth-sized"For the purpose of this 1 in 5 statistic, Earth-sized means 1–2 Earth radii. planet in the habitable zone. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brown Dwarf
Brown dwarfs (also called failed stars) are substellar objects that are not massive enough to sustain nuclear fusion of ordinary hydrogen ( 1H) into helium in their cores, unlike a main-sequence star. Instead, they have a mass between the most massive gas giant planets and the least massive stars, approximately 13 to 80 times that of Jupiter (). However, they can fuse deuterium ( 2H), and the most massive ones (> ) can fuse lithium ( 7Li). Astronomers classify self-luminous objects by spectral class, a distinction intimately tied to the surface temperature, and brown dwarfs occupy types M, L, T, and Y. As brown dwarfs do not undergo stable hydrogen fusion, they cool down over time, progressively passing through later spectral types as they age. Despite their name, to the naked eye, brown dwarfs would appear in different colors depending on their temperature. The warmest ones are possibly orange or red, while cooler brown dwarfs would likely appear magenta or black to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photometry (astronomy)
Photometry, from Greek '' photo-'' ("light") and '' -metry'' ("measure"), is a technique used in astronomy that is concerned with measuring the flux or intensity of light radiated by astronomical objects. This light is measured through a telescope using a photometer, often made using electronic devices such as a CCD photometer or a photoelectric photometer that converts light into an electric current by the photoelectric effect. When calibrated against standard stars (or other light sources) of known intensity and colour, photometers can measure the brightness or apparent magnitude of celestial objects. The methods used to perform photometry depend on the wavelength region under study. At its most basic, photometry is conducted by gathering light and passing it through specialized photometric optical bandpass filters, and then capturing and recording the light energy with a photosensitive instrument. Standard sets of passbands (called a photometric system) are defined to allow a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astrometry
Astrometry is a branch of astronomy that involves precise measurements of the positions and movements of stars and other celestial bodies. It provides the kinematics and physical origin of the Solar System and this galaxy, the Milky Way. History The history of astrometry is linked to the history of star catalogues, which gave astronomers reference points for objects in the sky so they could track their movements. This can be dated back to Hipparchus, who around 190 BC used the catalogue of his predecessors Timocharis and Aristillus to discover Earth's precession. In doing so, he also developed the brightness scale still in use today. Hipparchus compiled a catalogue with at least 850 stars and their positions. Hipparchus's successor, Ptolemy, included a catalogue of 1,022 stars in his work the '' Almagest'', giving their location, coordinates, and brightness. In the 10th century, Abd al-Rahman al-Sufi carried out observations on the stars and described their positions, ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
White Dwarf
A white dwarf is a stellar core remnant composed mostly of electron-degenerate matter. A white dwarf is very dense: its mass is comparable to the Sun's, while its volume is comparable to the Earth's. A white dwarf's faint luminosity comes from the emission of residual thermal energy; no fusion takes place in a white dwarf. The nearest known white dwarf is at 8.6 light years, the smaller component of the Sirius binary star. There are currently thought to be eight white dwarfs among the hundred star systems nearest the Sun. The unusual faintness of white dwarfs was first recognized in 1910. The name ''white dwarf'' was coined by Willem Luyten in 1922. White dwarfs are thought to be the final evolutionary state of stars whose mass is not high enough to become a neutron star or black hole. This includes over 97% of the other stars in the Milky Way. After the hydrogen- fusing period of a main-sequence star of low or medium mass ends, such a star will expand to a red giant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Dwarf
''Red Dwarf'' is a British science fiction comedy franchise created by Rob Grant and Doug Naylor, which primarily consists of a television sitcom that aired on BBC Two between 1988 and 1999, and on Dave since 2009, gaining a cult following. The series follows low-ranking technician Dave Lister, who awakens after being in suspended animation for three million years to find that he is the last living human, and that he is alone on the mining spacecraft ''Red Dwarf''—save for a hologram his deceased bunkmate Arnold Rimmer and "Cat", a life form which evolved from Lister's pregnant cat. As of 2020, the cast includes Chris Barrie as Rimmer, Craig Charles as Lister, Danny John-Jules as Cat, Robert Llewellyn as the sanitation droid Kryten, and Norman Lovett as the ship's computer, Holly. To date, twelve series of the show have aired, (including one miniseries), in addition to a feature-length special ''The Promised Land''. Four novels were published from 1989 to 1996. Two pilot ep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Exoplanet Search Projects
The following is a list of exoplanet search projects. Ground-based search projects Space missions Past and current Planned Proposed * EXCEDE * FINESSE * Origins * HabEx * LUVOIR * New Worlds Mission * PEGASE Canceled * Darwin * EChO * Eddington * Space Interferometry Mission * Terrestrial Planet Finder The Terrestrial Planet Finder (TPF) was a proposed project by NASA to construct a system of space telescopes for detecting extrasolar terrestrial planets. TPF was postponed several times and finally cancelled in 2011. There were two telescope ... References {{Exoplanet, state=uncollapsed Exoplanetology Search projects ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
