Thursday, April 7, 2011

The Hunt For New Planets

The Extra Terrestrial Planets
They have been among the hottest things in astronomy for more than a decade. But let's face it. Giant Jupiters, fried Neptunes, inflated fat Saturns, pairs of giants in resonant orbits - these are just lead-ups to the main act. What we really need to know about are Exo-Earths. By an "Earth," astronomers generally mean a planet that's small enough to have a solid, rocky surface but big enough to hold a considerable atmosphere, and maybe with the possibility of "liquid" water. In other words, a place where life as we know it might arise and remains. Perhaps even, with a lot of luck, a place where humans could someday walk around on it's surface with nothing more than an oxygen tube, or even without.

Wednesday, April 6, 2011

Is This an Alien Planet

Most methods for finding extra-solar planets favor worlds very close to their stars. Direct imaging, on the other hand, favors those far away - at least when it looks for an object's own infrared heat glow, rather than reflected starlight. Young giant planets should still be glowing from the heat of their formation. This Gemini Observatory infrared image shows the young star 1RXS J160929.1-210524 and a suspected planet-mass object 2.2 arc seconds from it. This separation amounts to at least330 astronomical units (8 times Pluto's average distance from the Sun) at the star's distance of 500 light-years.