A satellite the size of a school bus is expected to fall back to Earth sometime this weekend, NASA reports.
Upper Atmosphere Research Satellite, or UARS, is expected to re-enter Earth's
atmosphere late this month or early next month, almost six years after the end
of a productive scientific life, the space agency reported. Although the
spacecraft will break into pieces during re-entry, not all of it will burn up
in the atmosphere, the agency warned.
in a statement NASA claimed the risk to public safety or property is "extremely
small" and reiterated that safety is NASA's top priority. As of Friday
morning, the orbit of UARS was 100 miles by 105 miles. Re-entry is expected
late today or early Saturday, Sept. 24. The agency said solar activity is no
longer the major factor in the satellite's rate of descent and the satellite's
orientation or configuration apparently has changed, and that is now slowing
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," NASA said in a statement posted on its Website. "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."
UARS satellite, launched in 1991 from the space shuttle Discovery, was the
first multi-instrumented satellite to observe numerous chemical constituents of
the atmosphere with a goal of better understanding atmospheric photochemistry
and transport. The school bus-sized satellite, which is 35 feet long and 15
feet in diameter, weighs 13,000 pounds, and carries 10 instruments, also
provided key data on the amount of light that comes from the sun at ultraviolet
and visible wavelengths. UARS ceased its productive scientific life in 2005.
addition to numerous other scientific accomplishments, UARS data also marked
the beginning of numerous long-term data records for many key chemical species
in the atmosphere. This data is now being combined with more recent data sets
(especially from NASA's Aura satellite) to better understand how the atmosphere
reacts to the policies set down by the Montreal Protocol (an international
treaty to protect the ozone layer by phasing out production of substances
responsible for ozone depletion) as well as changes in climate drivers.
the beginning of the Space Age in the late-1950s, there have been no confirmed
reports of an injury resulting from re-entering space objects, nor is there a
record of significant property damage resulting from a satellite re-entry,
according to NASA. That didn't stop late-night TV comedian Stephen Colbert,
host of the satirical news program "The Colbert Report," from poking
fun at NASA's advisory. "Let's just pray it lands somewhere where it can't
do any damage-like Detroit," he quipped.