UARS Decay Rate Slows; U.S. May Be at Risk After All

NASA has pushed back by a few hours the time when its Upper Atmosphere Research Satellite (UARS) is expected to reenter, which changes the locations where the debris may fall.

Yesterday, NASA forecast that the satellite would reenter this afternoon or early evening. Its track would not take it over North America at that time so the United States was not at risk.

Since then, the satellite changed its orientation or configuration, slowing the decay rate slightly and pushing reentry later into the evening or early Saturday according to NASA’s latest update, posted as of 10:30 am EDT today. NASA now reports that it cannot rule out the possibility that debris might land in the United States:

“Solar activity is no longer the major factor in the satellite’s rate of descent. The satellite’s orientation or configuration apparently has changed, and that is now slowing its descent. There is a low probability any debris that survives re-entry will land in the United States, but the possibility cannot be discounted because of this changing rate of descent. It is still too early to predict the time and location of re-entry with any certainty, but predictions will become more refined in the next 12 to 18 hours.”

The chances of any debris causing “a” human casulaty anywhere on Earth is one in 3,200 according to NASA, but calculations by The Weather Channel clarify that the chances that any particular individual — you –will be hit is more like one in 20 million. The Earth is 70 percent covered by water, so there is a good chance it will not hit land at all.