Astronomy is the study of celestial bodies. Or, basically, the universe. Planets, stars, nebulae, asteroids,comets etc.
If you're unfamiliar with astonomy, the most interesting topics tend to be travel,goldilocks planets and generally strange planets/stars.
here's a video on strange planets:
http://www.youtube.com/watch?v=jOBjlZz5ZHk&feature=related (it's a long documentary btw.)
Let's start with the discussion of Gliese 581a,b,c,d,e,f,g
(If you're unfamiliar with astronomical charting, It's done in a system of (region name) (number of system) (celestial body) So Gliese 581 a is the star in it's system. Gliese 581 b is the first discovered planet. Gliese 581 c is the second discovered planet, etc.
Gliese 581 is a star system about 22 light years from our solar system.
On the left is the sun, on the right is Gliese 581. Gliese 581 is a red dwarf star.
It contains 2/3 of the top-6 planets listed for habitability. Here is a chart of the habitable or "goldilocks" zone of our solar system and the Gliese 581 system:
Note on that diagram the location of Earth, Gliese581g and Gliese581d.
Let's discuss astronomy now.
/engage discussion
