The McMurdo Dry Valleys are an excellent place to study terrestrial geology, but they can also be studied as an analog for Mars. Today the surface of Mars is very geologically active compared to other planets. We can see dust storms, observe the changing shape of the polar ice caps and even image ice sublimating (going straight from its solid state to a vapor) from the surface of the planet. Today Mars is a very cold and dry planet. So when we want to study the geologic processes active on Mars today the McMurdo Dry Valleys serve as an excellent analog because of their low precipitation rate and extreme cold temperatures.
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Image of the surface of Mars, taken from the Viking 1 lander. |
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| Image of Wright Valley, taken through my snow goggles to give everything an orange color. |
On Thanksgiving Kate, Jen and I decided to walk down to the Onyx River. It flows through Wright Valley and is the longest river in Antarctica. Once we got down to the valley floor we spent some time watching the water flow in the river. It was nice to see something moving for a change. As we were getting up to leave we saw some dust devils form on the opposite side of the river. A dust devil is similar to a mini-tornado, but the winds do not have to be very strong and they are only able to pick up fine particles such as dust and sand. At first there was only one, but a few minutes later another dust devil formed. They only lasted for approximately 5 minutes before disappearing. The appearance of these dust devils gives another example of features found on Mars that have also been observed in the Dry Valleys.
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| Picture of Wright Valley and Onyx River, taken from the valley floor. Note the beautiful U-shape of the valley, indicating it has been carved by glaciers. Valleys cut by rivers are usually V-shaped. |
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| Dust devil on opposite bank of Onyx River. |
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| Dust devil filmed on Mars by the Mars Exploration Rover Spirit in 2005. |
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