OGLE-2003-BLG-235L (MOA-2003-BLG-53L) is a star in the

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The first constellati ...

Sagittarius Sagittarius ( ) may refer to: *Sagittarius (constellation) *Sagittarius (astrology), a sign of the Zodiac * Sagittarius of Gap, a 6th century bishop *Sagittarius A*, the supermassive black hole at the center of the Milky Way galaxy Ships *'' S ...

. The first

gravitational microlensing Gravitational microlensing is an astronomical phenomenon caused by the gravitational lens effect. It can be used to detect objects that range from the mass of a planet to the mass of a star, regardless of the light they emit. Typically, astronom ...

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 The Optical Gravitational Lensing Experiment (OGLE) is a Polish astronomy, astronomical project based at the University of Warsaw that runs time-domain astronomy, a long-term variability sky survey (1992–present). The main goals are the detecti ...

(OGLE) and the

Microlensing Observations in Astrophysics Microlensing Observations in Astrophysics (MOA) is a collaborative project between researchers in New Zealand and Japan, led by Professor Yasushi Muraki of Nagoya University. They use gravitational microlensing, microlensing to observe dark mat ...

(MOA), hence, the double designation. It is an

orange dwarf A K-type main-sequence star, also referred to as a K-type dwarf, or orange dwarf, is a main-sequence (hydrogen-burning) star of spectral type K and luminosity class V. These stars are intermediate in size between red M-type main-sequence stars ("r ...

star of spectral type K, which is accompanied by a

giant planet A giant planet, sometimes referred to as a jovian planet (''Jove'' being another name for the Roman god Jupiter (mythology), Jupiter), is a diverse type of planet much larger than Earth. Giant planets are usually primarily composed of low-boiling ...

Lens system

OGLE-2003-BLG-235L and MOA-2003-BLG-53L is the designation given to the star in the lens system. In 2004, analysis of the light curve produced as it passed in front of the source star allowed detection of an

exoplanet An exoplanet or extrasolar planet is a planet outside the Solar System. The first confirmed detection of an exoplanet was in 1992 around a pulsar, and the first detection around a main-sequence star was in 1995. A different planet, first det ...

orbiting the star with a mass 0.0039 times that of the host star (this would put it in the

jovian Jovian is the adjectival form of Jupiter and may refer to: * Jovian (emperor) (Flavius Iovianus Augustus), Roman emperor (363–364 AD) * Jovians and Herculians, Roman imperial guard corps * Jovian (lemur), a Coquerel's sifaka known for ''Zobooma ...

mass range). The star was originally assumed to be a

red dwarf A red dwarf is the smallest kind of star on the main sequence. Red dwarfs are by far the most common type of fusing star in the Milky Way, at least in the neighborhood of the Sun. However, due to their low luminosity, individual red dwarfs are ...

star, since they are the most common type of star in the galaxy. By 2006, the source and lens star had moved far enough apart (as viewed from Earth) that their light could be separated. Observations by the

Hubble Space Telescope The Hubble Space Telescope (HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the Orbiting Solar Observatory, first space telescope, but it is one of the largest and most ...

revealed that in fact the lens star was actually brighter and less red than expected, matching the expected spectra for a K dwarf of about 0.63

solar mass The solar mass () is a frequently used unit of mass in astronomy, equal to approximately . It is approximately equal to the mass of the Sun. It is often used to indicate the masses of other stars, as well as stellar clusters, nebulae, galaxie ...

es, more massive than the average star in the galaxy. This enables an estimate of the distance to the lens star, which puts it at around 5.8 kiloparsecs (19,000 light years) away.

Planetary system

The OGLE-2003-BLG-235L/MOA-2003-BLG-53L system consists of one planet as determined by the discovery team and the follow-up confirmation observations.

References

External links

* K-type main-sequence stars Sagittarius (constellation) Planetary systems with one confirmed planet Gravitational lensing {{main-star-stub ru:OGLE-2003-BLG-235Lb

Lens system

Planetary system

See also

References

External links