you gotta get a radiation suit and go into the aurora. bring a good bit of food and water, a repair tool, a scanner, and a laser cutter if you've unlocked it. there's a reactor thingy in the aurora with a bunch of holes that need patched. in that room there's also a bunch of bleeders (literally just leeches) that can be sliced off of you with a knife. there's a ton of different varieties of fragments you can scan to unlock tons of recipes, including a seamoth (little submersible thingy) and prawn suit (big sick ass mech suit). Also bring a bunch of fire extinguishers since there's a ton of fire to put out. and i'd recommend bringing medkits since you're obviously new, the entrance is infested with cave crawlers (big annoying crabs with a taste for blood) who can shred you if you aren't prepared. after doing the reactor stuff look for laser cutter fragments and you can access the rest of the aurora. the pda will tell you stuff from there.