![]() An artist's impression of MOA-2007-BLG-192Lb orbiting its primary. | |
Discovery | |
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Discovered by | Bennett et al. |
Discovery site | Mount John University Observatory, ![]() |
Discovery date | 30 May 2008 |
Gravitational microlensing | |
Orbital characteristics | |
2.02±0.44 AU [1] | |
Star | MOA-2007-BLG-192L |
Physical characteristics | |
Mass | 12.49+65.47 −8.03 ME (likely between 3 and 12 ME) [1] |
MOA-2007-BLG-192Lb, occasionally shortened to MOA-192 b, [2] is an extrasolar planet approximately 7,000 light-years away in the constellation of Sagittarius. The planet was discovered orbiting the low-mass star MOA-2007-BLG-192L. It was found when it caused a gravitational microlensing event on May 24, 2007, which was detected as part of the MOA-II microlensing survey at the Mount John University Observatory in New Zealand. [3]
The mass of the planet is not well-known. It is anything between 2.75 and 105 Earth masses (ME), although it is more likely to be between 3 and 12 ME. The mass range also means that the planet's classification varies, from a Super-Earth to a Sub-Saturn. It is located at 2.02 astronomical units from its host star. [1]
Observation data Epoch J2000.0 Equinox J2000.0 | |
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Constellation | Sagittarius [lower-alpha 1] |
Right ascension | 18h 18m 03.8s [1] |
Declination | −27° 09′ 00.27″ [1] |
Characteristics | |
Evolutionary stage | Red dwarf |
Spectral type | M [1] |
Astrometry | |
Distance | 7040±980 ly (2160±300 pc) [1] |
Details | |
Mass | 0.28±0.04 [1] M☉ |
Database references | |
SIMBAD | data |
MOA-2007-BLG-192L is a red dwarf star, one of the smallest and least massive type of stars, as well as one of the most numerous in the Milky Way. [4] It was initially estimated to have a mass 6% the mass of the Sun, which would probably be too low to sustain nuclear fusion at its core, making it a dimly glowing brown dwarf. [5] However, this mass was based on an erroneous parallax, and a further analysis suggest a higher mass of 0.24 M☉. This would make it a red dwarf. [1]
Both MOA-2007-BLG-192L and its planet are located at a distance of 2,160 pc (7,000 ly ) from Earth, [1] in the direction of the constellation Sagittarius. [lower-alpha 1]
OGLE-2005-BLG-390Lb is a super-Earth exoplanet orbiting OGLE-2005-BLG-390L, a star 21,500 ± 3,300 light-years from Earth near the center of the Milky Way, making it one of the most distant planets known. On January 25, 2006, Probing Lensing Anomalies NETwork/Robotic Telescope Network (PLANET/Robonet), Optical Gravitational Lensing Experiment (OGLE), and Microlensing Observations in Astrophysics (MOA) made a joint announcement of the discovery. The planet does not appear to meet conditions presumed necessary to support life.
OGLE-2005-BLG-390L is a star thought to be a spectral type M. This galactic bulge star is located in the Scorpius constellation at a far distance of about 21,500 light years, near the border with Sagittarius.
OGLE-2003-BLG-235L (MOA-2003-BLG-53L) is a star in the constellation of Sagittarius. The first gravitational microlensing event for which a planet orbiting the lens was detected around this star. The event occurred in during July 2003. Two groups observed and independently detected the event: the Optical Gravitational Lensing Experiment (OGLE) and the Microlensing Observations in Astrophysics (MOA), hence, the double designation. It is an orange dwarf star of spectral type K, which is accompanied by a giant planet.
OGLE-2005-BLG-169L is a dim and distant magnitude 20 galactic bulge star located about 2,700 parsecs away in the constellation Sagittarius. If it is a main sequence star, then it is most likely a red dwarf with about half of the mass of the Sun. Other possibilities are a white dwarf star, or a neutron star or black hole.
MACHO-1997-BLG-41, commonly abbreviated as 97-BLG-41 or MACHO-97-BLG-41, was a gravitational microlensing event located in Sagittarius which occurred in July 1999. The source star is likely a giant or subgiant star of spectral type K located at a distance of around 8 kiloparsecs. The lens star is a binary system approximately 10,000 light-years away in the constellation Sagittarius. The two stars are separated from each other by about 0.9 AU and have an orbital period of around 1.5 years. The most likely mass of the system is about 0.3 times that of the Sun. Star A and star B are both red dwarfs.
OGLE-2005-BLG-169Lb is an extrasolar planet located approximately 2,700 parsecs away in the constellation of Sagittarius, orbiting the star OGLE-2005-BLG-169L. This planet was discovered by the OGLE project using the gravitational microlensing method. Based on a most likely mass for the host star of 0.49 solar mass (M☉), the planet has a mass of 13 times that of Earth (ME). Its mass and estimated temperature are close to those of Uranus. It is speculated that this planet may either be an ice giant like Uranus, or a "naked super-Earth" with a solid icy or rocky surface.
A Super-Earth is a type of exoplanet with a mass higher than Earth's, but substantially below those of the Solar System's ice giants, Uranus and Neptune, which are 14.5 and 17 times Earth's, respectively. The term "super-Earth" refers only to the mass of the planet, and so does not imply anything about the surface conditions or habitability. The alternative term "gas dwarfs" may be more accurate for those at the higher end of the mass scale, although "mini-Neptunes" is a more common term.
MOA-2007-BLG-400L is a star located 22472.1 light-years away in the constellation of Sagittarius. This star is presumed to be a red dwarf with a spectral type of M3V, based on its mass of 0.35 MS.
MOA-2007-BLG-400Lb is an extrasolar planet located approximately 20000 light-years away in the constellation of Sagittarius, orbiting the star MOA-2007-BLG-400L. This planet was detected on September 18, 2008 by the gravitational microlensing by Dong. It has mass between 50% and 130% of Jupiter and orbits between 0.6 and 1.1 AU.
MOA-2008-BLG-310L is a 23rd magnitude star located at least 20000 light years away in the constellation Scorpius. This star has mass 0.67 solar masses which imply that it could probably be a late K-type star.
MOA-2008-BLG-310Lb is an extrasolar planet which orbits probably the late K-type star MOA-2008-BLG-310L, located at least 20000 light years away in the constellation Scorpius. This planet has mass 23% of Jupiter or 77% of Saturn and orbits at 1.25 AU from the star. This planet was discovered by using the gravitational microlensing method on August 4, 2009. As it is typical for exoplanets detected by microlensing method, the orbital period and eccentricity are not determined.
The Microlensing Follow-Up Network is an informal group of observers who monitor high magnification gravitational microlensing events in the Milky Way's Galactic Bulge. Its goal is to detect extrasolar planets via microlensing of the parent star by the planet. μFUN is a follow-up network - they monitor microlensing events identified by survey groups such as OGLE and Microlensing Observations in Astrophysics (MOA).
MOA-2009-BLG-387Lb is an exoplanet in the orbit of the red dwarf MOA-2009-BLG-387L. Its discovery was announced on February 21, 2011, making it the eleventh planet discovered using gravitational microlensing. The planet is thought to be over twice the mass of Jupiter and to have an orbit 80 percent larger than that of Earth's, lasting approximately 1,970 days. However, its exact characteristics are difficult to constrain because the characteristics of the host star are not well known.
MOA-2009-BLG-387L is a red dwarf in the Sagittarius constellation that is host to the planet MOA-2009-BLG-387Lb. The star is estimated to be nearly 20,000 light years away and approximately one fifth the mass of the Sun, although large confidence intervals exist, reflecting the uncertainties in both the mass and distance. The star drew the attention of astronomers when it became the lens of gravitational microlensing event MOA-2009-BLG-387L, in which it eclipsed a background star and created distorted caustics, an envelope of reflected or refracted light rays. Analysis of the caustic events and of follow-up observational data led to the planet's discovery, which was reported in February 2011.
MOA-2010-BLG-477L is a star whose existence was detected when it caused a microlensing event in August, 2010. The microlensing event also revealed the existence of a planet orbiting the star. At first the star was thought to be about 0.67 times the mass of the Sun, in the main-sequence phase of its stellar evolution. But by the time the star should have been separated enough in the sky from the source star of the microlensing event it was not detected, implying that it is actually a dim white dwarf star.
OGLE-2016-BLG-1195Lb is an extrasolar planet located about 22,000 light-years from Earth, in the galactic bulge, orbiting the 0.57±0.06 M☉ star OGLE-2016-BLG-1195L, discovered in 2017. The planet was detected using gravitational microlensing techniques managed by the Korea Astronomy and Space Science Institute and the Spitzer Space Telescope. Initially, it was believed the planet has a mass similar to Earth and is located about the same distance from its host star as the Earth is from the Sun, although it was expected to be much colder.
OGLE-2016-BLG-1190Lb is an extremely massive exoplanet, with a mass about 13.4 times that of Jupiter (MJ), or is, possibly, a low mass brown dwarf, orbiting the G-dwarf star OGLE-2016-BLG-1190L, located about 22,000 light years from Earth, in the constellation of Sagittarius, in the galactic bulge of the Milky Way.
MOA-2011-BLG-262L is an astronomical object of uncertain nature with an orbiting companion, detected through the gravitational microlensing event MOA-2011-BLG-262 in the constellation Sagittarius. Two different models fit the observation equally well - an object of ~3.2 MJ, likely a rogue planet, at a distance of about 0.56 kiloparsecs and orbited by a ~0.47 M🜨 exomoon; or an object of ~0.11 M☉, likely a red dwarf star, at a distance of about 7.2 kiloparsecs in the galactic bulge, and orbited by a ~17 M🜨 planet. The discovery team considers the latter scenario to be more likely, but the former is a better fit.
KMT-2022-BLG-0440L b is a Neptune-like exoplanet, located 11,415 light years away in the constellation of Sagittarius. It was discovered in 2023.