ISS Expose-E seems to support the idea of panspermia
(Note to Mods, I’ve not used images so as not to infringe copyright laws and used Italics to emphasize quotes taken from other references on the net
and provided the source material)
Ok first off I’ve used the search function to find out if this has been brought to the board in the past, I can find many references to
‘panspermia’ but with recent results uncovered on the ISS I’d like to reopen the topic, what I want to bring to the board today is all based
around science fact, not the theory that little green men from the planet zeeboro-centintee seeded life on Earth.
What is panspermia?
The theory that micro-organisms or biochemical compounds from outer space are responsible for originating life on Earth and possibly in other parts
of the universe where suitable atmospheric conditions exist.
source
What is the Expose-E experiment?
Exposure Experiment (Expose) is a multi-user facility having a box-shaped structure accommodating experiments in the following disciplines: photo
processing, photo-biology and exobiology.
source
In layman’s terms the experiment comprises of a suitcase sized box with compartments divided into two layers of three experiment trays, each holding
four square boxes. Some of these boxes hold an array of biological or biochemical samples in small compartments. These are then exposed to varying
degrees to the harsh environment of space, including hard vacuum, extreme temperature changes and radiation. One experiment had gas inside the box
with an optical filter imitating the solar spectrum and the atmosphere of Mars.
Expose-E, was launched in February 2008 aboard Space Shuttle Atlantis and carried back to Earth by Space Shuttle Discovery in September 2009. A total
of 664 biological and biochemical samples were exposed to open space for 18 months.
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In the Expose experiment they used a variety of organisms, some of these included lichens, water-bears, brine shrimp and larvae of the African midge
Polypedilum vanderplank.
I’ll concentrate on two of the experiments that I find very fascinating.
Water Bears (or ‘Tardigrades')
Tardigrades, or Water Bears, or Moss Piglets are a small phylum of around 1000 known species of truly amazing animals that capture the hearts of
all that get to know them. (435 species are know from Europe) They are related to arthropods, probably originating from a similar proto-arthropod
ancestor. They have an external cuticle, though it is built up from a protein compound called an albuminoid rather than from the chitin that comprises
the insect cuticle.
source
Truly amazing little critters, some species can survive temperatures as low as -200 for more than 20 days and others can survive temperatures as high
as 125C well above the boiling point of water. Makes my head boggle thinking about the conditions some of these small phylum can survive in. They
survived in perfect health upon their return to Earth with some even going on to reproduce.
Xanthoria Elegans (Common Names: Elegant Sunburst, Elegant Orange, Elegant
Orange Wall Lichen, and Rock Orange)
Bright orange foliose lichen on rock. Surface somewhat coarse. Underside pale, with very few hapters. Apotheciate. All orange pigment K+ instantly
deep wine red.
source
This amazing lichen can be found in some of the most inhospitable places on Earth, they have the capability to ‘switch off’ if they find
themselves in conditions unsuited to their environment, once they return to a better suited environment they carry on living, the lichen has been used
for many things here on Earth including, lichenometry (dating of exposed rock) and can provide lichen extracts for cancer-preventing effects, (the
extract of X. elegans shows significant ability to enhance the activity of quinone reductase, an enzyme that breaks down certain potential
carcinogens, rendering them less harmful)
The Lichen survived the exposure on the ISS and went on to be described by some scientists that “they are the best survivors we know,”
So here we have two examples of life that can survive in the harshness of space, some even go on to reproduce, the problem with the panspermia theory
so far isn’t the survival in space, it’s the entry process into Earth’s atmosphere, this problem is being thought about and the possibility of
life surviving this process deep inside a space rock has been put out there by René Demets, a biologist working in the ESA.
Quote:
“The loose end in this theory is now arrival at a planet, because no living thing can survive the fiery entry through an atmosphere, But
possibly deep inside a space rock the conditions are better. Therefore we’re now thinking of an astrobiology experiment involving a return to
Earth”.
source
I for one eagerly await this experiment and it’s results, because my own personal belief is life was seeded on Earth from other planets, some of the
facts I’ve found on the net and brought before the board here back that theory i.e. life can survive in space, the next step is to confirm the entry
process is possible, if it is possible we have a very good case for 'panspermia' not being a theory anymore, it’ll be a possibility backed by
science fact.
[edit on 4-2-2010 by Majestic RNA]