02/15/11 – Ephemeris – Kepler discoveres lots of planets
Tuesday, February 15th. The sun will rise at 7:43. It’ll be up for 10 hours and 27 minutes, setting at 6:10. The moon, 3 days before full, will set at 6:20 tomorrow morning.
Two weeks ago NASA announced the discovery of a possible 12 hundred and 35 planets around other stars discovered by the Kepler spacecraft mission, which has been staring at a single patch of the Milky Way for nearly two years. It found 5 earth-like planets in the habitable zones of their stars. It’s finding planets by their passage in front of their stars, something astronomers call transits. A very useful technique but only a few percent of star systems are so perfectly oriented to our line of sight to produce these transits. Most of these finds have to be verified by the Doppler wobble method of the planet’s effects of the motion of the star itself. Kepler even found a six planet system all orbiting within a few million miles of their star.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Bob Moler's Ephemeris Blog 