◌  Kepler 4b

21 August 2010

There is a star called KIC 11853905 at RA 19^h 02^m 27.68^s, δ +50° 8′ 8.7″ – behind the Little Dipper by about two of its lengths – that dims by one thousandth every 84 hours and 31 minutes or so. This is what it looks like if we stack graphs of successive dimmings:

This is how we know there’s a planet orbiting that star. It’s called Kepler-4b, and its radius is about 3.8× Earth’s, but it’s a gas giant; at its surface you would weigh only about half again as much as you do here. It’s the smallest discovered (non-secret) extrasolar planet.

In the next few years we should have curves like this for several rocky, Earth-sized planets. In the next decades we’ll be able to figure out their atmospheres and, eventually, if we spend the money, if they’re there, we could see weather and continents. I would not be surprised if we learn in my lifetime that something is metabolizing outside our solar system.

Thanks to Cory’s post on CP 1919 for reminding me to look at this data. Thanks to Nasa for the data. This is a pretty quick and dirty visualization, with some eyeballing to account for intra-cycle trends; I’ll do a neater job when they get around to releasing the good stuff.