APOD 4.05

This skyview is of Gliese 581, a star system only 20 light years away in Libra. What is amazing is that there are 3 confirmed planets orbiting this planet, with one being the most Earth-like ever discovered. This "Super Earth," as it is being called, is about 5 times as massive as the Earth, and has a diameter of about 1.5 that of Earth's. It's orbit is about 14 times less then that of the Earth's, which makes it orbit once every 13 days. Gliese 581 is a red-dwarf, which makes its habitable zone much smaller, but the "Super Earth" resides in it, which means its mean surface temperature is 0 - 40 C, making liquid water possible.

APOD 4.4

Planet HD 209458b is so close to its parent star that it is evaporating. Its atmosphere is expanding away from it. Scientists believe they have detected water vapor in the atmosphere, from spectroscopic evidence. If this is true, this would be the first confirmed instance of planetary water outside of our Solar System. This could mean the possibility of life outside of our Solar System.

Galaxy Links

http://en.wikipedia.org/wiki/Galaxy
http://www.damtp.cam.ac.uk/user/gr/public/gal_lss.html
http://www.astr.ua.edu/keel/galaxies/agnintro.html
http://www.berkeley.edu/news/media/releases/2006/01/09_warp.shtml
http://www.nasa.gov/mission_pages/galex/galex-20061205.html