How GPI Works to See Planets

I sometimes compare the challenge of directly detecting a Jupiter orbiting a nearby star to finding a glowing needle in a haystack.  Oh, and by the way, the haystack is on fire.

It’s about as hard as seeing a candle a foot away from a spotlight (1 million candlepower) at a distance of 100 miles.

Why is doing this so difficult?  There are three primary reasons:

Peering at Planets

Astronomers and engineers recently completed building the Gemini Planet Imager (GPI) to study distant solar systems. GPI will obtain high-resolution images of extrasolar planets by blocking the light of stars and detecting the faint thermal glow of orbiting planets.

Near-infrared image of Beta Pictoris b, an extrasolar planet approximately 60 light years away. The light of the host star, Beta Pictoris, is blocked in this image to reveal the much fainter light of the planet. Image processing by Christian Marois, NRC Canada.