Tag: mars

Sending Invasive Species to Mars

George Dvorsky summarizes a new study showing six types of bacteria found in Siberia are able to survive, and even thrive, under Mars-like conditions.

The researchers took these cultures [from Siberian permafrost] and exposed them to similar conditions found on Mars, including a severe lack of oxygen, extreme cold temperatures, and very low pressure (about 150 times lower than the Earth’s, about 7 millibars). The experiment was run over the period of 30 days. Over 10,000 isolates were exposed to these conditions — and they all died.

Except six.

And in fact, these six surviving microbes actually did better under these conditions. Surprised by the result, the researchers took a closer look at the survivors, and following a genetic analysis concluded that they all came from the same genus: an extremely hardy extremophile called Carnobacterium.

— Dvorsky (2012): Scientists show that microbes from Earth can survive conditions found on Mars in io9.

So now we have to wonder if we’ve already, inadvertently, sent life to Mars.

Landing the Mars Rover: 7 Minutes of Terror

NASA gets dramatic. But the drama is oh so appropriate when you see what they have to do to land a rover on Mars. There are so many steps to the landing — heat shields, atmospheric friction, parachute, rockets — that it’ll be amazing if it works, and the video is a wonderful “strike the imagination” introduction to the physics of forces.

Why are Earth’s Sunsets Red While Mars’ are Blue?

The area around the Sun is blue on Mars because the gasses in the thin atmosphere don't scatter much, but the Martian dust does (it scatters the red). Image via NASA.

The dust in Mars’ atmosphere scatters red, while the major gasses in Earth’s atmosphere (Nitrogen and Oxygen) scatter blue light. Longer wavelengths of light, like red, will bounce off (scatter) larger particles like dust, while shorter wavelengths, like blue light, will bounce of smaller particles, like the molecules of gas in the atmosphere. The phenomena is called Rayleigh scattering, and is different from the mechanism where different molecules absorb different wavelengths of light.

Ezra Block and Robert Krulwich go into details on NPR.

Blue sky in the upper right, but the dust scatters the red light.

Terraforming Mars

Image Credit: NASA/JPL-Caltech

Jason Shankel has an article on how we could go about changing the surface of Mars into something humans can live on. He does an excellent job of condensing the not insignificant literature on terraforming the red planet.

Starting with an explanation of Mars’ geologic history, Shankel addresses Martyn Foggs’ list of critical challenges:

  1. The surface temperature must be raised
  2. The atmospheric pressure must be increased
  3. The chemical composition of the atmosphere must be changed
  4. The surface must be made wet
  5. The surface flux of UV radiation must be reduced

— Shankel (2011): How We Will Terraform Mars on io9.com.

The Martian Surface as seen by the rover Opportunity. Image Credit: NASA/JPL-Caltech/Cornell/ASU

The article is expansive in its detail, provides a wonderful primer on the red planet, and demonstrates an excellent application of planetary system science (as opposed to Earth system science) to what would be an enormous geoengineering project. For example, to warm up the planet, Shankel starts with several approaches:

so how do we warm up the Martian poles? Several approaches have been suggested, from spreading dark material on the poles to lower their albedo, to industrial ice farming to good old fashioned thermonuclear detonations.

— Shankel (2011): How We Will Terraform Mars on io9.com.

He then goes into detail. Lots of detail, in a quite readable form.

A desert in Algeria. Image by islapics via Wikimedia Commons.

Gypsum on Mars

Suspected gypsum vein on Mars. Image taken by the Opportunity Rover. Image credit: NASA/JPL-Caltech/Cornell/ASU.

NASA thinks their rover has found veins of gypsum on Mars. If they have, it will be an excellent indication that there was once standing water on Mars — gypsum is usually precipitated in evaporating lakes — and will excite the search for life on Mars.

What gypsum veins on Earth look like: white gypsum veins from Somerset, UK. Image by Ashley Dace. (via Wikipedia)

Signs of Water on Mars?

Water is necessary for life as we know it, which is why the search for life on other planets and moons in the solar system has been focused first of all on finding water. NASA now reports signs of water on Mars. Salty water perhaps, and even now there is no direct evidence that it is water and not some other fluid, but this is the first evidence of there being liquid water on Mars today.

The video above explains, and the BBC has a good article.

Life on Mars

Discover Magazine has a great article summarizing the evidence for life on Mars. It’s long because it goes into a lot of detail examines quite a variety of possibilities, but it ties quite nicely in with the questions we are asking about what is life and where it can be found.

The article also mentions a study titled, “The Limits of Organic Life in Planetary Systems” produced by the National Research Council for NASA. It can be found for free online, with an associated podcast that much more accessible to middle schoolers. The report is extremely open to the possibility that extra-terrestrial life exists, and could exist even without water and might even be silicon based.