Fly to Knowhere. It's easy to find- just second star to the right, and straight on 'til the giant decomposing skull.
Enter through the eye socket. On the ledge you'll see the Knowhere map kiosk.
Once inside, smash what you can smash. The smashables stage left will yield pieces that can be built into a web-yankable cabinent. Yank it.
These pieces yield a grav booster, which can be activated for some fixable debris centerstage.
Fix it to gain entry to the mission proper.