So I was watching some videos on terraforming and I had this idea that sounds good but I am sure has a problem with it somewhere cause otherwise everyone would mention it.

When it comes to terraforming Mars the consensus is that we gotta cause some martian warming to thicken the atmosphere. Never mind making it breathable, we can do that later. We first need something thick enough to vaccum succ us dead in a few dozen seconds.

Plenty of suggestions about how to do this. Mirrors, mateor strikes, atom bombs etc. But one I never see mentioned is methane and water.

It's a well known fact that Titan has a few trillion gallons of methane and other hydrocarbons inside it's thicc atmosphere and oceans of it. Methane and hydrocarbons like that are very powerful greenhouse gasses. Europa is also known to have a huge ass ocean under it's ice that is full of water, likely salty but we don't know yet. Water vapour is also very good at storing thermal energy and quite good at greenhouse effect. Why not use those?

The idea would be to create large satellites and park them in orbit of said moons. Then they would be filled with either methane or water. These spaceships would be very bare bones: A simple engine, some basic metal sheet/foil and a hollow center to be filled with the stuff. The idea would be to make them huge, like a kilometre across at least. They could be filled with the stuff. These simple spaceships would then be put in a collision course with Mars and sent away.