MOA-2007-BLG-192L
Encyclopedia
MOA-2007-BLG-192L is a low-mass red dwarf
star
or brown dwarf
, approximately 3,000 light-year
s away in the constellation
of Sagittarius
. It is estimated to have a mass approximately 6% of the Sun
's. In 2008, an Earth
-sized extrasolar planet
was announced to be orbiting this object.
, orbiting this object was announced on June 2, 2008. This planet, with a mass of approximately 3.3 times that of Earth
, is one of the smallest known extrasolar planets
. It was found when it caused a gravitational microlensing
event on the night of May 24, 2007, which was detected as part of the MOA-II
gravitational microlensing survey at the Mount John University Observatory
in New Zealand
.
Red dwarf
According to the Hertzsprung-Russell diagram, a red dwarf star is a small and relatively cool star, of the main sequence, either late K or M spectral type....
star
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...
or brown dwarf
Brown dwarf
Brown dwarfs are sub-stellar objects which are too low in mass to sustain hydrogen-1 fusion reactions in their cores, which is characteristic of stars on the main sequence. Brown dwarfs have fully convective surfaces and interiors, with no chemical differentiation by depth...
, approximately 3,000 light-year
Light-year
A light-year, also light year or lightyear is a unit of length, equal to just under 10 trillion kilometres...
s away in the constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
of Sagittarius
Sagittarius (constellation)
Sagittarius is a constellation of the zodiac, the one containing the galactic center. Its name is Latin for the archer, and its symbol is , a stylized arrow. Sagittarius is commonly represented as a centaur drawing a bow...
. It is estimated to have a mass approximately 6% of the Sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...
's. In 2008, an Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
-sized extrasolar planet
Extrasolar planet
An extrasolar planet, or exoplanet, is a planet outside the Solar System. A total of such planets have been identified as of . It is now known that a substantial fraction of stars have planets, including perhaps half of all Sun-like stars...
was announced to be orbiting this object.
Planetary system
The discovery of a planet, MOA-2007-BLG-192LbMOA-2007-BLG-192Lb
MOA-2007-BLG-192Lb, occasionally shortened to MOA-192 b, is an extrasolar planet approximately 3,000 light-years away in the constellation of Sagittarius. The planet was discovered orbiting the brown dwarf or low-mass star MOA-2007-BLG-192L. At a mass of approximately 3.3 times Earth, it is one of...
, orbiting this object was announced on June 2, 2008. This planet, with a mass of approximately 3.3 times that of Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
, is one of the smallest known extrasolar planets
Extrasolar planet
An extrasolar planet, or exoplanet, is a planet outside the Solar System. A total of such planets have been identified as of . It is now known that a substantial fraction of stars have planets, including perhaps half of all Sun-like stars...
. It was found when it caused a gravitational microlensing
Gravitational microlensing
Gravitational microlensing is an astronomical phenomenon due to the gravitational lens effect. It can be used to detect objects ranging from the mass of a planet to the mass of a star, regardless of the light they emit. Typically, astronomers can only detect bright objects that emit lots of light ...
event on the night of May 24, 2007, which was detected as part of the MOA-II
Microlensing Observations in Astrophysics
Microlensing Observations in Astrophysics is a collaborative project between researchers in New Zealand and Japan, led by Professor Yasushi Muraki of Nagoya University. They use microlensing to observe dark matter, extra-solar planets, and stellar atmospheres from the Southern Hemisphere...
gravitational microlensing survey at the Mount John University Observatory
Mount John University Observatory
Mount John University Observatory , is New Zealand's premier astronomical research observatory. It is situated at ASL atop Mount John at the northern end of the Mackenzie Basin in the South Island, and was established in 1965...
in New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
.
See also
- HD 181433
- HD 40307
- HD 47186HD 47186HD 47186 is a star located approximately 129 light-years away in the constellation of Canis Major. It is a G6V star with the characteristics very similar to the Sun, but it is 1.7 times more metal-rich. In 2008, two extrasolar planets were discovered orbiting the star.- Planetary system :Announced...
- MOA-2007-BLG-400LMOA-2007-BLG-400LMOA-2007-BLG-400L is a star located approximately 20000 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.-Planetary system:...
- OGLE-2005-BLG-390LOGLE-2005-BLG-390LOGLE-2005-BLG-390L is a star thought to be a spectral type M - red dwarf star OGLE-2005-BLG-390L is a star thought to be a spectral type M - red dwarf star OGLE-2005-BLG-390L is a star thought to be a spectral type M - red dwarf star (95% probability, 4% probability it is a white dwarf,...