Some orbits are quicker than others. Cloudsat was recently retired, and was lowered to a graveyard orbit which decays a lot more quickly. As I understand it, our collective space programs have made a bit of a mess of operational orbits and we need to think about cleaning up debris while also mitigating any future additions to the debris field.
All orbits are decaying without periodic adjustments. If you disable a satellite, it will eventually burn up in the atmosphere.
Some orbits are quicker than others. Cloudsat was recently retired, and was lowered to a graveyard orbit which decays a lot more quickly. As I understand it, our collective space programs have made a bit of a mess of operational orbits and we need to think about cleaning up debris while also mitigating any future additions to the debris field.