This will be my first time keeping a (research) blog, and the aim
is to keep it both informative and personal. In a couple of days I will be
going to McMurdo station, Antarctica to start a month long field season that
will start in McMurdo station, and ultimately end in University Valley, one of
the coldest and driest places on earth. What brings me there is an ASTEP funded
project, which will be testing the IceBreaker drill, a prototype drill which is
designed to pierce into the frozen soils of Mars. University Valley is one of
the most Mars-like places on Earth, and so that's where the drill is going to
be tested! Lucky for me (a microbiologist) its also a really great spot to look
for extremophiles which are pushing the limits of life.
What I'm interested in are the psychrophillic (also called
cryophillic) microorganisms that are found in this harsh environment.
Psychrophiles are organisms that not only survive, but thrive in really cold
environments.
Life needs water to survive, and one result of freezing
temperatures is a lack of liquid water (since water turns to ice). Cold adapted
bacteria need to cope with a lack of water as well as cold (high salt
concentrations too...but more on that another time).
How cold can they go?
The lowest temperature at which microbial growth has been recorded
is -15 C, found in a microbe called Planococcus halocryophilus OR1, which was isolated from permafrost (ground which doesn't go
above freezing) in the Canadian High Arctic. Active, respiring microbial
cells have been measured in samples down to -20 C in Siberian permafrost samples. These are examples of extremophiles which are making a living in the
cold.
University Valley, Antarctica will be a harsh place to be, year
round temperatures that never go above 0 C, and next to no precipitation in the
form of snow. Whats more, in University Valley, sublimation processes dominate,
so water either exists as ice, or directly sublimates into vapour, there is no
liquid water in the surface soils! Not a nice place to live, even if you are a
tough bacterium. What this results in, is an area with dry, desert sand
on the surface, and frozen ice-cemented ground underneath. Because temperatures
don't go above freezing, these are two types of permafrost! This is really
neat, because this is only observed in one area on earth, and is similar to
what was observed at the Pheonix landing site on Mars. If we can find life
thriving in this environment on Earth, it may mean its possible for similar
life to occur on Mars.
I am a microbiologist looking for life in University Valley, but the science team who will be going to University Valley is a diverse group of scientists who will be trying to answer different science questions (in addition to testing the IceBreaker drill), like, where did the ice-cemented ground come from? why is the ice still there since sublimation processes dominate? how old is the ice?
Very excited to work with these people, and very excited to look for microbes in this Mars-like environment!
I am a microbiologist looking for life in University Valley, but the science team who will be going to University Valley is a diverse group of scientists who will be trying to answer different science questions (in addition to testing the IceBreaker drill), like, where did the ice-cemented ground come from? why is the ice still there since sublimation processes dominate? how old is the ice?
Very excited to work with these people, and very excited to look for microbes in this Mars-like environment!
