Kepler’s Return: Planet-Seeking Telescope Going Into Orbit
It’s funny. I was watching Science Channel HD last night, and after a Killer Asteroids show, a show came on about Planet Hunters. And then this morning, I find out that the Kepler Telescope is being launched today. Weird. It’s like the Universe is trying to tell me something…like write about planet hunting.
After years and years of using Earth-based telescopes to find planetary cousins, NASA is moving the base of operations (well, the “eye” of operations) to an Earth orbit in order to get past the cloudy, hazier Earth atmosphere. One of the obstacles that planet-hunting scientists have is that atmosphere, and much like the Hubble Telescope, imaging of distant objects gets waaay better off-planet.
The Kepler Telescope has been designed with planet hunting in mind, and in particular Earth-alikes. Named for the guy who formulated the laws of planetary motion, Johannes Kepler. The key to finding a planet is patience, obviously, but also a keen eye. As planets are not stars, seeing them is a bit tricky. Astronomers have to look for “wobbles” in a star’s light, as seen from our perspective. The wobble or slight dip in the star’s brightness signifies that something is moving (or has, as looking at lights in space is like looking back in time) across the star’s face. Earth would be just a wobble across our Sun to those living across the Milky Way.
So, NASA is sending up the Kepler to look for wobbles…for three and a half years. In fact, a true wobble won’t be detected for those three years. The Kepler will be looking at a specific patch of sky up to 3,000 light years away in the vicinity of the constellations Cygnus and Lyra.
Kepler will stare at the region for at least 3 1/2 years, measuring the light from 100,000 stars every half hour with a 95 million-pixel camera to watch for the slight dip in a star’s brightness that signals a planet moving across it as seen from Earth. It’s the equivalent of trying to spot a flea crawl across a car headlight from miles away, NASA has said. –Space.com
Once a wobble is found, and found again the next two years, to find another Earth-like planet, the planet has to be within a certain distance from whatever star it calls its Sun. Too close, like that little planet found last month by the European’s COROT space telescope, and the planet may be way too hot. Too far, and it could be too cold. Usually, the presence of water is the benchmark for Earth-iness. Of course, the size of the exosolar “sun” also matters, as a larger sun will provide more heat to planets farther away, and vice versa.
Kepler launches tonight (March 6) at 10:49 EST with a back-up window again at 11:13pm EST. If you are along the East Coast, try to get out and find the newest addition to the firmament as it heads towards orbit.
Kepler, Earth, NASA, telescope, space, Hubble telescope, space exploration, Cygnus, Lyra, planet hunting, planets, Milky Way, Sun, COROT, stars, universe, Science Channel
