Gemini Planet Imager takes its first pictures

The Gemini Planet Imager (GPI) has released its first image of an exoplanet.  GPI, a special camera that works with the 8.1-meter Gemini South telescope in Chile, was designed to observe exoplanets, or planets outside of our solar system.  A big problem for directly imaging exoplanets is that they orbit stars; you just can't see them because they are so faint compared to the whopping bright star sitting right next to them.  The GPI uses fancy techniques to block out light from the host star and sharpen images by correcting for turbulence in the Earth's atmosphere.  The result? Amazing images like the one below of exoplanet Beta Pictoris B, a planet orbiting a star about 63 light years away.  

GPI first light image of Beta Pictoris B.  The large circle is the star, the smaller one is the planet. (Image credit: Processing by Christian Marois, NRC Canada)

GPI first light image of Beta Pictoris B.  The large circle is the star, the smaller one is the planet. (Image credit: Processing by Christian Marois, NRC Canada)

GPI observes planets in infrared light; this is because planets glow mostly in infrared due to their (relatively) low temperatures (the human body also emits mostly at infrared wavelengths).  It will observe mostly Jupiter-sized planets that orbit their stars at about the distance Jupiter orbits the Sun.  It's a revolutionary instrument, because to date, we've only taken images of a handful of exoplanets.  GPI will increase this number by a lot!  

GPI also offers us a new way to detect exoplanets.  In contrast to instruments like Kepler, which detected planets by looking for dips in the light output of a star from a planet crossing in front of it, GPI can just point at a star and see in the image taken whether a planet is there.  In the next year, it will start a survey of 600 young stars to see how many giant planets orbit them.  This offers us an incredibly direct way to get at the fraction of stars that have Jupiter-like planets orbiting them.  It will be exciting to see how GPI advances our knowledge of exoplanets! 

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