September 1991 photo shows the Upper Atmosphere Research Satellite (UARS) in the grasp of the remote manipulator system end effector above the payload bay of shuttle orbiter Discovery during STS-48 pre-deployment checkout procedures. Credit: NASA
NASA’s Upper Atmosphere Research Satellite, or UARS, is expected to re-enter later this month.
According to a NASA-posted UARS update, as of Sept. 12th, the orbit of UARS was 145 mi by 165 mi (235 km by 265 km).
Re-entry is expected during the last week of September, according to NASA and the Joint Space Operations Center of U.S. Strategic Command at Vandenberg Air Force Base, Calif., which works around the clock detecting, identifying and tracking all man-made objects in Earth orbit, including space junk.
The UARS anticipated fall to Earth is almost six years after the end of a productive scientific life.
Although the spacecraft will break into pieces during re-entry, not all of it will burn up in the atmosphere. The risk to public safety or property is extremely small, and safety is NASA’s top priority.
Because the satellite’s orbit is inclined 57 degrees to the equator, any surviving components of UARS will land within a zone between 57 degrees north latitude and 57 degrees south latitude.
It is impossible to pinpoint just where in that zone the debris will land, but NASA estimates the debris footprint will be about 500 miles long.
The UARS satellite, launched in 1991 from the Space Shuttle, was the first multi-instrumented satellite to observe numerous chemical constituents of the atmosphere with a goal of better understanding atmospheric photochemistry and transport.
By Leonard David