First light images emerge from Gemini Planet Imager

llnl.gov

97 points·nkvl··9 comments

Incredible image for an Earth-based telescope. I wonder what we could get from space?

It would probably be worse from space, actually. This was imaged at the diffraction limit of the telescope (~λ/D where D is the diameter of the mirror) and Gemini has an 8-meter mirror. We're not going to put an 8-meter IR telescope in space for a long time. Even JWST is only 4 meters.

Is visible light interferometry possible with multiple small reflectors in orbit?

It is, but the limit is your ability to cram it all that in a single rocket. It's why the James Webb needs foldable mirrors (JWST is made of small mirrors stuck together basically).

There have been a few proposals for in-space interferometers, but budgeting shot them down for the most part. In hindsight they may have been cheaper given the ballooning costs of JWST.

That's very interesting, didn't know that. Thanks.

Truly awesome! I am curious what part of the light spectrum did they use to take the picture? If it was said in the article then I missed it.

The Gemini Planet Imager operates at "near-infrared" wavelengths (Y - K bands), according to Wikipedia. The telescope is designed to detect light generated by the heat of young planets, so infrared is the best bet, I think.

Y band is 1 μm, K band is 2.2 μm [1]. Almost all current adaptive optics systems work in the infrared.

[1] http://en.wikipedia.org/wiki/Photometric_system

The star is 237 lightyears from earth. Incredible.

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