Can living organisms survive a terribly harsh, years-long trek to Mars’ moon Phobos and then back to Earth? That's the question asked by the Planetary Society's Living Interplanetary Flight Experiment (LIFE) as it prepares to leave for the Red Planet later this month.
“It’s a wonderful experiment,” says Bill Nye, Planetary Society CEO. “This is the next logical step in answering the fundamental questions: “Where did we come from?” and “Are we alone?”
The Phobos LIFE biomodule is hitching a ride on the Russian Phobos Sample Return Mission, also known as Phobos Grunt. ("Grunt" is the Russian word for soil.) Liftoff from Kazakhstan on a Zenit 2 rocket may happen as soon as November 8, when the launch window opens.
The Society is sending this simulated meteoroid to test an important aspect of the transpermia hypothesis--that life may be able to travel between planets inside space rocks, blasted from one planetary surface to another.
Inside the patented Phobos LIFE “biomodule,” along with a larger soil sample container, are thirty tiny tubes, each just three millimeters across. They contain millions of non-pathogenic organisms from all three domains of life: bacteria, archaea, and eukaryota. The eukaryota include hundreds of plant seeds, and scores of little critters called Tardigrades. Seen under a microscope, these animals somewhat resemble their nickname--Water Bears. They are the most complex organisms making the round trip, which will last approximately three years.
David Warmflash is the Phobos LIFE Science Principal Investigator. "We know that many of the species aboard Phobos LIFE are incredibly hardy," says Warmflash. "Many can be described as 'extremeophiles.' Some are quite complex, yet they can survive or even thrive in environments that are toxic for other complex organisms, such as humans. We can't wait to get them back in our labs to see how they've been affected by this especially challenging exposure."
Phobos LIFE will be the first test of organisms’ long-term survivability outside the Earth’s protective magnetosphere. Almost all other such tests of space survival skills have lasted a few days or weeks. The handful of longer experiments were conducted in Earth orbit, well within our planet's strong magnetic field. The magnetosphere deflects the majority of cosmic and solar radiation that makes interplanetary space so hazardous to complex life forms.
Scientists estimate that about one Mars meteoroid reaches Earth each month. More than thirty have been positively identified. Many of their trips to our home world are much longer than the journey that will be made by Phobos Sample Return, but some predicted trajectories are similar to the path of the spacecraft. The biomodule itself is an impressive engineering achievement. Weighing just 88 grams, and easily held in the palm of your hand, it can withstand a 4000 g impact (4,000 times the force of gravity) without any leaks in even the first level of seals. This is a vital design requirement. Phobos LIFE is mounted inside the sample return capsule, which will make its fiery descent to Earth without a parachute.
This amazing durability will also protect Mars from contamination by Earth organisms in the extremely unlikely possibility of an impact there. The spacecraft is carefully designed to land only on Phobos, and collect samples of the moon's surface, before the sample return capsule begins its long return voyage.
A real-life test of Phobos LIFE procedures using a subset of the organisms took place in May of this year, when the Shuttle LIFE experiment spent two weeks in Earth orbit aboard the STS-134 space shuttle mission. Analyses of these organisms continue.
After its landing in Kazakhstan, the still-sealed biomodule will go to the Manassas, Virginia labs of ATCC for unsealing opening and analysis. ATCC is the private, nonprofit, biological resource center and research facility where the Phobos LIFE organisms were packed away for their journey. The species samples provided by science team members in Russia, Germany, and Sweden will be returned to those labs for analyses, while the rest will be initially examined at ATCC then distributed for further study.
The Planetary Society's Bruce Betts is the Phobos LIFE Experiment Manager. "After years of preparation by our international team, it is exciting to be on the verge of launch,” says Betts. “It's so gratifying to see the worldwide enthusiasm for this very low cost yet highly ambitious effort."
Stellar Explorations, Inc. in San Luis Obispo, California provided engineering design and testing for the project. Also key to the effort are partnerships with Russian colleagues at the Space Research Institute and the Lavochkin Association. Additional mission participants are in Germany, Sweden, Japan and elsewhere around the globe. The complete Phobos LIFE mission team is listed here.
"In addition to the interesting science of the transpermia experiments, LIFE has a symbolic significance as the first directed sending of Earth life into interplanetary space," says Louis Friedman, the overall Principal Investigator for the experiment.