NASA
Monitoring The Collapse Of The Thermosphere:
"Something Is Going On That We Do Not
Understand"
NASA-funded researchers are monitoring a big event in
our planet's atmosphere. High above Earth's surface
where the atmosphere meets space, a rarefied layer of
gas called "the thermosphere" recently
collapsed and now is rebounding again. "This is
the biggest contraction of the thermosphere in at
least 43 years," says John Emmert of the Naval
Research Lab, lead author of a paper announcing the
finding in the June 19th issue of the Geophysical
Research Letters (GRL). "It's a Space Age
record." The collapse happened during the deep
solar minimum of 2008-2009—a fact which comes as
little surprise to researchers. The thermosphere
always cools and contracts when solar activity is low.
In this case, however, the magnitude of the collapse
was two to three times greater than low solar activity
could explain. "Something is going on that we do
not understand," says Emmert.