Астронет: Астрономическая картинка дня Тихоходка на мхе http://variable-stars.ru/db/msg/1378828/eng |
Credit & Copyright: Nicole Ottawa & Oliver Meckes / Eye of Science /
Science Source Images
Explanation:
Is this an alien?
Probably not, but of all the animals on Earth, the
tardigrade might be the best
candidate.
That's because
tardigrades
are known to be able to go for decades without food or water,
to survive temperatures from near
absolute zero
to well above the boiling point of water,
to survive pressures from near zero to well above that on
ocean floors,
and to survive direct exposure to dangerous
radiations.
The far-ranging survivability of these
extremophiles was
tested
in 2011 outside an orbiting space shuttle.
Tardigrades are so durable partly because they can repair their own
DNA
and reduce their body water content to a few percent.
Some of these
miniature
water-bears
almost became
extraterrestrials recently when they were launched toward to the Martian moon
Phobos on board the Russian mission
Fobos-Grunt, but stayed terrestrial
when a rocket failed and the capsule remained in Earth orbit.
Tardigrades are more common than humans across most of the Earth.
Pictured here in a color-enhanced
electron micrograph, a millimeter-long tardigrade crawls on
moss.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.