Color shot from Phoenix landing site. Courtesy of NASA.
The Mission
Rising from the ashes of the failed Mars Polar Lander in 1999, Mars Phoenix is NASA’s most recent mission to land on the “Red Planet.” The goal of Phoenix is simple: find out if there are or ever were the necessary ingredients on Mars for the development of primitive life. The mission will not look for life directly, it will search the soil of the Northern polar latitudes on Mars for primarily water and basic organic compounds. The discovery of either or both would be indicative of life, but would not yield direct evidence of its existence, past or present.
Phoenix is joining the aging Spirit and Opportunity rovers on Mars. The rovers landed in 2004 and Spirit, the first rover to land, is on Sol 1564 of its planned 90 Sol mission. A Sol is the time it takes Mars to rotate once on its axis, so it is the equivalent of a Martian day. Phoenix has a life expectancy of 90 Sols as well, although its lifespan is not dictated by the quality of the equipment on board, but rather the severity of the Martian winter which is expected to cause irreversible damage to Phoenix.
On tab for Phoenix this week is to get its robotic arm operational and for scientists on Earth to locate the site that Phoenix will sample first. The sampling procedure on Phoenix will involve the use of a scoop on the end of the robotic arm that will dig a trench 3 feet into the Martian permafrost. Soil from the sample will then be poured into an oven on the lander where it will then be heated to over 1000 degrees, vaporizing the soil. Instrumentation inside the oven will then measure the gases put off by the soil to determine it’s composition. There are only eight of these one-time use ovens, so only 8 samples will be taken for the duration of the mission.
The rest of the mission will be spent measuring different meteorological conditions at the site. The lander is at a latitude similar to Alaska and Greenland on Earth, so the weather is likely to be colder than on other regions of the planet where weather observations have been made. Currently, the only meteorological data gathered on Mars from the surface to date has been along equatorial regions.
My Opinion
Mars Phoenix is the next logical step in the exploration of Mars. Some might ask why we don’t just get a surface sample and return it to Earth or why it is even important to be exploring the polar region. First, for a sample return, we need to have a good idea of where we want the sample from.
Current conservativeestimates place a robotic sample return mission for Mars at around $3-4 billion. That price could be much higher. To put that into perspective, Phoenix cost $420 million, both Mars Exploration Rovers cost $820 million, and the up and coming Mars Science Laboratory is expected to cost around $2 billion, primarily due to the landing system necessary to land the 1,800 lbs rover. It is also important to remember that NASA’s FY 2008 budget is $17.3 billion dollars (0.6% of the $2.9 trillion budget). A Mars sample return is a significant investment.
Secondly, the polar region is critical in this build up to a sample return. It is only in the polar regions of Mars that substantial evidence exists to support the existence of water beneath the surface. Water is a fundamental building block of life, so this is an important region to explore. Plus, on Earth, even in the frozen Arctic and Antarctic regions, life forms called extremophyles have been found frozen in the ice. If life can exist under these conditions here on Earth, they cannot be ruled out on Mars.
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Useful sites for Mars Phoenix information:
NASA/JPL site: http://www.jpl.nasa.gov/news/phoenix/main.php
NASA site: http://www.nasa.gov/mission_pages/phoenix/main/index.html