Theworld may be abuzz these days with the release of the movie "Harry Potterand the Order of the Phoenix," but there is a real magical Phoenix in the news.
ThePhoenix Mars Mission, the first in NASA's "Scout Program", is set tolaunch the first week in August 2007 for a 10 month journey to the northernplains of Mars. Mars Scouts are low cost, competitively selected missions thatare intentionally outside the mainstream of NASA's Mars Exploration Program andare the scrappy underdogs of the space world. Phoenix certainly fits thisdescription, and for those who are always tempted to root for the underdog, Phoenix is a great cause.
Afterthe very public failures of two NASA missions (Mars Climate Orbiterand MarsPolar Lander) in 1999, NASA set out to completely restructure the MarsExploration Program (MEP). Scott Hubbard (currently Carl Sagan Chair for theStudy of Life in the Universe, SETI Institute) was sent to NASA Headquartersand dubbed NASA's "Mars Czar" in the press when he was chosen to headthe reorganization. Hubbard designed a program of alternating landers andorbiters to take advantage of each two-year launch opportunity to Mars (whenMars is in the right position in its trip around the sun to be more easilyreached from earth), and to have enough time between similar type missions totake advantage of lessons learned. The strategy has worked very well, and theMars Exploration Program (MEP) has been amazingly successful since therestructuring.
TheMars Scout Program was created when Hubbard and the science community soughtopportunities for missions outside the main stream of the MEP. This program wasspecifically established to provide an opportunity to capitalize on advancingtechnologies and innovations as well as to give the broader scientificcommunity the ability to explore Mars. Even though Mars Scouts were intended tobe low cost, relatively straightforward missions, few things about spaceexploration are ever simple or easy. The Phoenix mission development is noexception. Most of the Phoenix mission is the rebirth (hence, the name Phoenix) of the Mars Polar Lander (MPL) that crashed onto Mars in 1999. As always, duringthe development of any space mission lotsof hardware was built for all the tests and redundancies required to safelyfly a space mission. In addition, a follow-on mission to MPL had been planned,and then cancelled, which left a further legacy of hardware. Some of theinstrumentation was usable on Phoenix, which made it ideally suited to uncoverthe clues to the geologic history and biological potential of the Martianarctic.
Thestory of MECA, (Microscopy, Electrochemistry, and Conductivity Analyzer) whichincludes a wet chemical analyzer with a dual-use microscope, is a great exampleof how science instruments could be reused for a later mission. TheCo-Investigator for the microscope, John Marshall, of the Carl Sagan Center at the SETI Institute, felt strongly that Phoenix needed the microscope to fullyunderstand the processes that have influenced the northern terrain, but therewas a funding crisis and MECA was going to be cancelled. Marshall needed$250,000-and fast-to rescue the microscope. He cornered Scott Hubbard, thenDirector of NASA Ames Research Center, the man who had signed off on the ScoutProgram to begin with, and convinced him to find the money. In 48 hours, the$250,000 had been scraped together and MECA was saved.
Phoenix's mission is to use arobotic arm to dig through the protective top soil layer to the water ice belowand, ultimately, to bring both soil and water ice to the lander platform forsophisticated scientific analysis. But, like most scientific endeavors, findingwhat you are looking for is just the first step. Next you need to understandhow it, in this case, soil and the water mixed with it, got there and how ithas affected, and been affected by, its environment. The science team wants tounderstand the origin of the soil. Was it brought by wind? By water? Affectedby water and ice? What processes has it gone through? No single instrument cantell the whole story.
Thinkof the investigation as a several step process. MARDI, the Mars Descent Imager,will take pictures on the way to the Martian surface to give context. Are welanding on bedrock? Is this soil volcanic, blasted here by an ancient eruption?After landing, the solar arrays will be deployed, the MARDI images will be sentand the host of instruments will start whirring to action. Then, a Robotic Armwill reach out and deliver samples to either the TEGA (Thermal and Evolved GasAnalyzer) or MECA instruments. Now comes the turn for John Marshall'smicroscope. MECA consists of two microscopes, an optical microscope and anatomic force microscope (AFM) sharing some common parts, and complimenting oneanother. The optical microscope looks down to the level of silt and dust, andthe AFM looks further still, down to superfine dust.
AnotherPhoenix instrument, TEGA, a combination high-temperature furnace and massspectrometer instrument, will carry the story even further by looking at thechemistry of the icy soil to determine ratios of various isotopes of hydrogen,oxygen, carbon, and nitrogen, providing clues to origin of the volatilemolecules, and possibly, biological processes that occurred in the past.
NASA'sPhoenix Scout isn't a bit of fantasy, but it has, metaphorically, at least,risen from the ashes and its full suite of instruments was saved by a hair'sbreadth. Skill and passion, patience and hard work, lessons learned, care andexpertise will all come together very soon to make something that is its ownkind of magic – a space exploration mission.