Direct Image of an Exoplanet 155 Light Years Away - 0 views
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This week, an international team of researchers
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announced the discovery of an exoplanet
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155 light years
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world is estimated to be 11 times the mass of Jupiter — placing it just under the lower mass limit for brown dwarf status
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orbits its host star 2,000x farther than the distance from Earth to the Sun once every 80,000 (!) years
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The primary star, GU Psc A, is an M3 red dwarf weighing in at 35% the mass of our Sun and is just 100 million years old
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researchers targeted GU Psc after it was determined to be a member of the AB Doradus moving group of relatively young stars, which are prime candidates for exoplanet detection
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The fact that GU Psc B was captured by direct imaging at 155 light years distant is amazing
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The team was able to discern this curious planet by utilizing observations from the W.M. Keck observatory, the joint Canada-France-Hawaii Telescope, the Gemini Observatory and the Observatoire Mont-Mégantic in Québec.
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there are not a lot of exoplanets that were detected ‘directly’ so far
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The few planets for which we have an actual image are interesting because we can analyze their light directly, and thus learn much more about them
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researcher Marie-Ève Naud and her co-advisor Étienne Artigau
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also one of the “coolest” planets that have been directly imaged, showing methane absorption
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it is certainly the most distant exoplanet to a main-sequence star that has been found so far
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This distance makes GU Psc b very interesting from a theoretical point of view, because it’s hard to imagine how it could have formed in the protoplanetary disk of its star
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current working definition of an exoplanet is based solely on mass (<13 Jupiter masses), so GU Psc b probably formed in a way that is more similar to how stars formed
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how are astronomers certain that PU Psc b is related to its host and not a foreground or background object?
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As the host star, GU Psc is relatively nearby; it displays a significant apparent proper motion
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relative to distant background stars and galaxies.
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On images taken one year apart with WIRCam on the Canada-France-Hawaii Telescope, we observed that the companion displays the same big proper motion, i.e. they move together in the plane of the sky, while the rest of the stars in the field don’t
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most planet hunting techniques using direct imaging involve state-of-the-art adaptive optics systems, but we used ‘standard’ imaging without any exotic techniques
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To find this planet, we used very sensitive ‘standard’ imaging,
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we chose carefully the wavelengths where planets display colors that are unlike most other astrophysical objects such as stars and galaxies