OGLE-2003-BLG-235/MOA-2003-BLG-53

'OGLE-2003-BLG-235/MOA 2003-BLG-53' was a gravitational microlensing event which occurred in the constellation of Sagittarius during July 2003. The event was observed both as part of the Optical Gravitational Lensing Experiment (OGLE) and by the Microlensing Observations in Astrophysics group (MOA), hence the double designation.[1]
The source star in the gravitational lens is a main sequence star of spectral type G located around 8.8 kiloparsecs (29,000 light years) away in the galactic bulge. The lens star is an orange dwarf star of spectral type K, which is accompanied by a giant planet.[2]

Contents
Lens system
Planet
References
External links

Lens system


'OGLE-2003-BLG-235L/MOA-2003-BLG-53L' is the lens star. In 2004, analysis of the light curve produced as it passed in front of the source star allowed detection of an exoplanet orbiting the star with a mass 0.0039 times that of the host star (this would put it in the jovian mass range). The star was originally assumed to be a red dwarf star, since they are the most common type of star in the galaxy.1
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 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 masses, more massive than the average star in the galaxy.2 This enables an estimate of the distance to the lens star, which puts it at around 5.8 kiloparsecs (19,000 light years) away.


Planet

'OGLE-2003-BLG-235Lb' is an extrasolar planet discovered in 2004 by the OGLE and MOA collaborations. Its high mass indicates that it is most probably a gas giant planet similar to Jupiter. It is located around 4.3 AU away from its parent star.2


References


1. OGLE 2003-BLG-235/MOA 2003-BLG-53: A planetary microlensing event, Bond et al., , , Astrophysical Journal, 2004
2. Identification of the OGLE-2003-BLG-235/MOA-2003-BLG-53 Planetary Host Star, Bennett, D. P., Anderson, J., Bond, I. A., Udalski, A., Gould, A., , , The Astrophysical Journal, 2006

External links



Notes for star OGLE235-MOA53

Hubble site document 2006/38

HST image of planetary host star

★ SPACE.com: Hidden Star of Known Planet Found (Ker Than) 08 August 2006 01:01 pm ET

This article provided by Wikipedia. To edit the contents of this article, click here for original source.

psst.. try this: add to faves