The timing of a large NASA satellite's uncontrolled re-entry through the atmosphere has been narrowed to Friday, though officials say it's too early to predict exactly when or where it will occur.
An update today from the U.S. Strategic Command's Joint Space Operations Center, which tracks orbital debris, specifies Friday as the anticipated re-entry day. Earlier updates had projected Friday plus or minus a day, given uncertainties about the track of the six-ton decommissioned satellite.
As of this morning, the 35-foot-long, 15-foot-diameter Upper Atmosphere Research Satellite was flying between 120 miles and 130 miles above the planet.
NASA expects 26 pieces of the spacecraft to reach Earth somewhere between 57 degrees north or 57 degrees south of the equator, an area that includes most of the populated world.
The anticipated re-entry on Friday U.S.-time does not mean debris will land in the U.S. The predicted re-entry time and location "are becoming more refined."
Updates will follow 24 hours, 12 hours, six hours and two hours before the planned reentry. Find them here.
Click here for a USA TODAY story with more background.