But he also adds that re-entries are very much an inexact science. Even with the worldwide radar and telescope data that is at the U.S. government's disposal, it is virtually impossible to precisely predict where and when space debris will impact, says Nouis. U.S. Space Command will watch as Russia performs the maneuvers to send Mir back to Earth and then predict a 30-minute window when parts of Mir will hit the planet. If the aim were off, there's a slight chance that parts of the station could hit land. Emergency Management Australia has announced it is ready for the chance that something could go wrong.
Most objects are pieces of rockets or satellites.
Despite the frequency of space debris entering the atmosphere, there is no documented case of space debris causing injury to people on Earth, according to U.S. Space Command. Most objects burn up in the intense heat caused by the re-entry with only a small percentage making it to Earth. The odds that a person might be struck by a space debris are small, according the U.S. Space Command. Objects that survive the heat of the Earth's atmosphere are more likely to hit water rather than land, which covers only about 25 percent of the Earth's surface. ABC News Internet Ventures.