Answers Your Questions
| From: Dan Crosbie, of Wheatland,
To: Wayne Hale, flight director
Question: Why was the altitude of the ISS being increased?
Answer: Any object in low-Earth orbit is subject to orbital decay, caused in part by collisions with the molecules of the extremely thin upper atmosphere. This will, if unchecked, eventually result in the object deorbiting (Skylab, for example). The atmosphere expands and contracts in response to solar activity, so the orbital decay rate can vary. To counter this decay, the shuttle is called upon to reboost the station back into a higher orbit.