Optical Gravitational Lensing Experiment

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OGLE telescope at the Las Campanas Observatory
Artist's impression of the planet OGLE-2005-BLG-390Lb discovered by the OGLE Team
OGLE-IV Galactic Bulge fields with cadence, from OGLE-IV sky coverage.

The Optical Gravitational Lensing Experiment or OGLE is a Polish astronomical project based at the University of Warsaw that is chiefly concerned with discovering dark matter using the microlensing technique. Since the project began in 1992, it has discovered several extrasolar planets as a side benefit. The project is led by Professor Andrzej Udalski, who is a co-author of the discovery of OGLE-2005-BLG-390Lb.

The main targets of the experiment are the Magellanic Clouds and the Galactic Bulge, because of the large number of intervening stars that can be used for microlensing during a stellar transit. Most of the observations have been made at the Las Campanas Observatory in Chile. Cooperating institutions include Princeton University and the Carnegie Institution.

The project is now in its fourth phase. The first phase, OGLE-I (1992–1995), was the project pilot phase; for OGLE-II (1996–2000), a telescope was specially constructed, placed in Las Campanas Observatory and dedicated to the project. The 8-chip mosaic CCD camera was built in Poland and shipped to Chile. OGLE-III (2001–2009) was primarily devoted to detecting gravitational microlensing events and transiting planets in four fields: the Galactic Bulge, the constellation Carina,[1] and toward both Magellanic Clouds. As a byproduct of the constant monitoring of hundreds of millions of stars, the largest catalogs of variable stars were constructed, and the first exoplanets discovered using the microlensing technique were detected. In 2010, following engineering work in 2009, the fourth and current phase, OGLE-IV, was started using a 32-chip mosaic CCD camera. The main goal for this phase is to increase the number of planetary detections using microlensing, enabled by the new camera.

Recently OGLE team in cooperation with scientist mostly from USA, New Zealand and Japan proved that small, Earth-like planets can exist in great distance from stars around which they revolve despite there being other star near them.[2][3]

Planets discovered[edit]

At least seventeen planets have so far been discovered by the OGLE project. Eight of the planets were discovered by the transit method and six by the gravitational microlensing method.

Planets are shown in the order of discovery. Planets in multiple-planet systems are highlighted in yellow. Please note that list below may not be complete.

Star Constellation Right
ascension
Declination App.
mag.
Distance (ly) Spectral
type
Planet Mass
(MJ)
Radius
(RJ)
Orbital
period

(d)
Semi-major
axis

(AU)
Orbital
eccentricity
Inclination
(°)
Discovery
year
OGLE-TR-10[4][5] Sagittarius 17h 51m 28s −29° 52′ 34″ 15.78 5000 G2V OGLE-TR-10 b 0.63 1.26 3.10129 0.04162 0 84.5 2002
OGLE-TR-111 Carina 10h 53m 01s −61° 24′ 20″ 16.96 5000 G OGLE-TR-111 b 0.53 1.0 4.01610 0.047 0 88.1 2002
OGLE-TR-132 Carina 10h 50m 34s −61° 57′ 25″ 15.72 7110 F OGLE-TR-132 b 1.14 1.18 1.689868 0.0306 0 85 2003
OGLE-TR-56 Sagittarius 17h 56m 35s −29° 32′ 21″ 16.56 4892 G OGLE-TR-56 b 1.29 1.30 1.211909 0.0225 0 78.8 2003
OGLE-TR-113 Carina 10h 52m 24s −61° 26′ 48″ 16.08 1800 K OGLE-TR-113 b 1.32 1.09 1.4324757 0.0229 0 89.4 2004
OGLE-2003-BLG-235L
/MOA-2003-BLG-53L
Sagittarius 18h 05m 16s −28° 53′ 42″ 19000 K OGLE-2003-BLG-235Lb 2.6 4.3 2004
OGLE-2005-BLG-071L Scorpius 17h 50m 09s −34° 40′ 23″ 19.5 9500 M OGLE-2005-BLG-071Lb 3.5 3600 3.6 2005
OGLE-2005-BLG-169L Sagittarius 18h 06m 05s –30° 43′ 57″ 19.4 8800 M? OGLE-2005-BLG-169Lb 0.041 0.345 2006
OGLE-2005-BLG-390L Sagittarius 17h 54m 19s −30° 22′ 38″ 21500 M? OGLE-2005-BLG-390Lb 0.018 2006
OGLE-TR-211 Carina 10h 40m 15s −62° 27′ 20″ 5300 F OGLE-TR-211 b 1.03 1.36 3.67724 0.051 0 ≥87.2 2007
OGLE-TR-182 Carina 11h 09m 19s −61° 05′ 43″ 16.84 12700 G OGLE-TR-182 b 1.01 1.13 3.9791 0.051 0 85.7 2007
OGLE2-TR-L9 Carina 11h 07m 55s −61° 08′ 46″ 2935 F3 OGLE2-TR-L9 b 4.5 1.61 2.4855335 0.0308 2008
OGLE-2006-BLG-109L Sagittarius 17h 52m 35s −30° 05′ 16″ 4900 OGLE-2006-BLG-109Lb 0.71 1825 2.3 2008
OGLE-2006-BLG-109L Sagittarius 17h 52m 35s −30° 05′ 16″ 4900 OGLE-2006-BLG-109Lc 0.27 5100 4.8 0.11 59 2008
OGLE-2012-BLG-0026L 17h 34m 19s 17:34:19.0 −27° 08′ 34″ 4080 OGLE-2012-BLG-0026Lb 0.11 3.82 2012
OGLE-2012-BLG-0026L 17h 34m 19s −27° 08′ 34″ 4080 OGLE-2012-BLG-0026Lc 0.68 4.63 2012
OGLE-2011-BLG-0251 17h 38m 14s −27° 08′ 10″ 8232 M OGLE-2011-BLG-0251 b 0.53±0.21 2.72±0.75 or 1.5±0.5 2013

Notes: For events detected by the gravitational microlensing method, year stands for OGLE season, BLG means that an event detected is in the Galactic BuLGe, and the following 3-digit number is an ordinal number of microlensing event in that season. For events detected by the transit method TR stands for TRansit and the following 3-digit number is an ordinal number of transit event.

See also[edit]

References[edit]

External links[edit]

Coordinates: 29°00′36″S 70°41′56″W / 29.010°S 70.699°W / -29.010; -70.699