I want to partially terraform Venus, enough to make it feasible to mine minerals etc,. there. To do this I need to do a few things but for this question I'm focusing on stripping away at least some of the atmosphere either by design or by fortuitous accident.
Would a large asteroid or manmade object passing close to Venus' atmosphere on a one way trip to the Sun, made of a very dense material I just made up which is 100 times the density of Osmium be able to pull some or most of the atmosphere away from Venus. How big would it need to be, and how fast relative to Venus would it need to be moving? I don't want it pulling Venus out of orbit into the Sun as well.
Am I even correct in assuming a dense material has that sort of gravity power?