In space, no one can hear you scream, 'COCKROACH!'
 Q:
I know it's just a joke: astronauts cleaning bugs off their windshield on
a space walk. But it got me wondering. Do astronauts ever really see
bugs in space? Kori, Brantford, Canada
April 1, 2007. Astronaut Sunita Williams, her hair floating in free fall,
finds bacteria on the International Space Station. The Lab-on-a-chip
reader gives a strong positive reading from handrail swabs. Photo courtesy of NASA.
A: I asked
Mike Gentry and
James Hartsfield of the Johnson Space Center
in Houston about squished bugs on the shuttle 'windshield.'
"I'm not aware of any instance where insects have been seen, but we did have
an instance on STS-121 [Shuttle Discovery, July 2006] where bird droppings
were seen on the wing," emailed Hartsfield.
The birds released their droppings before the shuttle launched, but the
astronauts spotted them in space from a video taken to inspect the wing.
So, no dead insects that we've noticed, just bird droppings. But maybe,
by "bugs", you mean microscopic organisms — bacteria and fungi native to Earth.
Then, yes, astronauts really find bugs in space, and they can be a menace.
Astronauts, like all of us, have a collection of bacteria and fungi on and in their bodies. So bugs accompany the astronauts into
space. Astronauts can now detect them with a nifty
gadget (the Lab-on-a-chip Application Development-Portable Test System, called LOCAD-PTS for short).
The hand-held lab (see figure) can analyze a sample in about fifteen minutes (which
beats waiting the current 3-day growing-a-culture-in-a-petri-dish time).
We successfully tested LOCAD-PTS only this past April.
Microbes like a humid, moist environment. Sometimes they thrive in
human habitats orbiting in space. In fact, the environment on the Russian Mir station was so much to the bugs
liking that fungi colonies actually ate porthole glass, and destroyed
electronic equipment. Cosmonauts could barely see out of their porthole,
as an unknown film crept across the glass. Fungi
and bacteria colonies visible to the naked eye were the culprits. These tiny organisms
didn't actually eat glass; they ate skin cells and other human detritus.
Human organic discharge (from breathing, for example) entered the station atmosphere and eventually
collected on station
surfaces, says Natalia D. Novikova, head of a research group
at the Institute for Biomedical Problems in Moscow. Creeping
fungi ate the human byproducts, and excreted highly-corrosive waste products,
which etched porthole glass, its titanium mounting and also a control block for a communications
device. Acid waste from fungi can dissolve steel, glass and plastics.
 During twenty years of research on the Mir Station, Novikova's group found
107 species of fungi. The space bugs originated on Earth, but
mutated wildly in Mir's radiation level. So, in a real and scary sense,
they became 'space bugs.' Radiation in space is about 500 times more
intense than on Earth's surface.
Japanese researchers found colonies of Earthling microbes 7 miles (12 km)
above Earth at the upper edge of our lower atmosphere. The microbes
adapted to dry, thin air and intense ultraviolet radiation at seven miles high.
They are different from Earth surface bacteria. By the way, the
International Space Station's orbit is about 200 miles (330 km) up.
Artist’s
rendition of the Phoenix landing scheduled for April 2008 on the Martian arctic
plain. Pulsed rocket engines fire during the last few seconds of descent.
Drawing courtesy of NASA/JPL-Caltech/University of Arizona.
So far, astronauts and cosmonauts have only encountered Earth microscopic
organisms in space.
We have yet to see our first alien bug. But we're looking. On
Aug. 4, we launched the Mars probe, Phoenix, whose job is to find water, then
life or, at least, organic compounds. In April 2008, the probe will land
near the Martian North Pole ice cap, and start digging for bugs.
Further Reading:
Endosafe®-PTS™ completes journey to the International Space Station, Charles
River Laboratory
Outer space disinfection, Institute for Biomedical
Problems
Dividing bacteria
Cells Alive
Distribution of extremophiles in space environment, JSForum
Space fungus: a menace to orbital habitats, Space.com
No foolin' — Lab-on-a-chip works! science@NASA
Phoenix Mars Mission,
NASA
Looking for life on Mars, Marine Biological Laboratory
Are we
ready for alien bugs? Discover Magazine
(Answered Aug. 13, 2007)
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