The Wiki is your friend. But Saturn is your nearest accessible planet, unless you want to go to the Derelict.

Kk, how do I get to saturn? Also, what is the Derelict? Sorry about all of these questions. I am such a noob.  xD

You need to beat the boss on Mars - this chart is really useful: http://warframe.wikia.com/wiki/Planets

Derelict are high-level Infested missions, most of which have a chance of gaining Corrupted mods (if you are carrying the correct key to unlock the vault - so don't do these solo). You need nav coordinates to craft a starchart key to go to the derelict. Just as a note, derelict is a terrible way to farm resources, people mainly go for the corrupted mods and for the Nekros warframe.

Ok, thx for the help! I am on my school computer bc its the only place I check my emails. I never check my emails at home, since I'm busy doing school work or gaming. xD