vinnylo
aka peepers is a 28.49 year old boy, has been a member since July 10, 2007, has scored 36,405 submissions, giving an average score of 1.81, helping 515 designs get printed.
I think you should lose the text on the earth sun and moon.
If you want them there, then how about adding on the other parts as well. Something like:
earth and moon = night
earth and sun = day
moon and sun = eclipse
Use a different typeface, and if you are to include more type, use both a serif and sans serif. Also use two different sizes (one for the serif and other for sans serif) Try out some of these:
perpetua
adobe song
hoefler text
gotham
eurostyle
Add some complexity to the earth, and sun... like there is on the moon. Maybe even utilize photos to gain texture and detail which adds richness and depth and the obvious(realism).
When you present it, dont have it on that grungy backdrop Its not being printed on a stone or piece of old paper. I think this confuses some people and could jeopardize a positive vote.
I agree, the grunge backdrop makes it look very dark, and it is kinda the opposite of what you are going for. Also, my lack of science knowledge is astounding, but I'm not sure how the three elements come together and make life.
You might be trying to cram too many ideas here: Venn diagram + CYMK + an astronomy-related fact that's hard to explain graphically and not so many people are aware of.
I do hope you find a way though coz I like it ;)