A new probe to a Martian moon may win back respect for Russia’s unmanned space program.
- By Anatoly Zak
- Air & Space magazine, September 2008
Imagine a world-class athlete who hasn’t practiced for several years, but suddenly gets a chance to compete at the Olympics. Or an opera singer walking on stage at La Scala without a rehearsal. These would be good metaphors for Russia’s Phobos-Grunt mission. (“Grunt,” pronounced “groont,” is Russian for “soil.”) Planned for launch in October 2009, the probe may become the first to land on Phobos, the larger of Mars’ two moons, and the first to bring a sample of its soil back to Earth, so scientists can try to determine whether Phobos was once an asteroid. And it will mark the revival of Russian planetary science after two decades of decline.
Even during the years of the space race with the United States, when Soviet space budgets were hefty, the nation’s Mars ambitions frequently met with failure. Of the 20 Soviet or Russian missions aimed at the Red Planet, not one fully succeeded. Other countries have had their troubles too. Five of NASA’s 19 Mars missions have failed. Japan’s only attempt, launched in 1998, failed to achieve orbital insertion. In 2003, the European Space Agency’s sole effort has imaged the planet from orbit, but the lander vanished in the Martian atmosphere.
In late 1996, Russia made its last attempt to leave Earth orbit: Mars-96, a complex mission consisting of an orbiter, two landers, and two surface penetrators. Unlike the Soviet Union, which always launched planetary exploration spacecraft in pairs, Russia could afford only a single spacecraft. With funding always in doubt, many of the project’s participants worked for months without pay. Mars-96 finally reached the launch pad at the Baikonur Cosmodrome in Kazakhstan.
On November 16, 1996, Vasili Moroz, a leading scientist at the Russian Space Research Institute, or IKI, the Russian equivalent of NASA’s Jet Propulsion Laboratory, watched the launch from mission control near Moscow. The blastoff of the Proton rocket seemed flawless. A mission commentator gave optimistic reports on the various stages of the climb to orbit. “As we learned later,” said Moroz, who died in June 2004, “the commentator was reading a previously prepared list of the orbital insertion sequence rather than reacting to real events. We thought everything was fine, and even had a little drink to celebrate…. Of course we shouldn’t have done that.” Shortly thereafter, Moroz dropped by a ballistics calculations room where an operator reported that a propulsion system failure had left the craft in a doomed orbit around Earth. It soon plunged into the atmosphere over the Pacific Ocean.
“The loss of Mars-96 was extremely difficult to survive,” says Vechaslav Linkin, another IKI veteran. “Imagine: busy, busy work and then suddenly it is all over. We started losing employees. Some found work abroad. I lost several very talented guys, the developers of the software for the Mars rover.”
But in the new millennium, fortunes started to change. Skyrocketing oil prices boosted Russia’s energy-focused economy. Eventually, money trickled down to the space institute. By 2007 its budget was fully funded, and the loss of talent was stanched. “We now get many young specialists,” says Lev Zelenyi, who has led IKI since 2002. “With the brain drain of the 1990s, we kind of lost a middle generation who could now transfer their experience to young specialists. It is almost like during the war. We have a kind of generation gap.”
With the worst behind them, Russian scientists young and old are poised to study Mars and Phobos in a single mission. Unlike sister moon Deimos, Phobos, named for the Greek god of fear, the mythical son of Ares (whom the Romans called Mars), circles the Red Planet in a relatively low orbit, and is therefore the easier of the two moons to access.
“It is not the most interesting asteroid in the solar system,” says Francis Rocard, manager of solar system programs at Centre National d’Etudes Spatiales, France’s space agency. CNES has supplied a gas analysis package to study the molecular composition of Phobos’ soil. “But we will have access to it, and we will probably confirm that it is effectively a captured asteroid.” Rocard hopes the probe will find Martian material on Phobos; if so, it would have got there the way some of it reached Earth: by ejection of Martian materials during impacts of asteroids or big meteorites.
The spacecraft, which is being assembled near Moscow at NPO Lavochkin, successor to the Soviet Lavochkin Design Bureau, should reach Mars in late July or early August 2010. It will orbit the planet for almost nine months before landing on Phobos. There it will be subjected to power and communications blackouts, when Mars and Phobos block the sun and Earth.
“Phobos ends up in the shadow of Mars,” explains Aleksandr Zakharov, deputy director of IKI. “In the worst situations, this shadow lasts for almost an hour out of an eight-hour orbit.”
Immediately after the touchdown, Phobos-Grunt will load a soil sample into a return rocket. In case of a breakdown of communications with mission control, it can enter an emergency mode to collect samples and still send them home in the return rocket. Normal collection could last from two days to a week.
“There are a number of complications in taking that soil,” Zakharov says. “We are working in near-weightlessness, and to test this on Earth is practically impossible. Therefore, we go into all kinds of tricks.”
Scientists hope that Phobos-Grunt will beam to Earth a panoramic view of Phobos’ surface to help scientists select targets. For collection, engineers had hoped to use a variation of a drill the Soviet Luna probes employed to return samples of Earth’s moon in the 1970s. But in the low gravity on Phobos, which has an average diameter of less than 14 miles, the spacecraft will weigh less than a pound. The action of a drill might overturn the lander, depending on how hard a surface it encounters. So IKI developed a small robotic arm to scoop spots around the craft.
“Obviously, [the scoop] loses the ability to drill deep into the surface, as Luna did,” Zakharov says. “However—and I was personally involved in the analysis of it—the drills by Luna to the depths of more than one meter showed that there is not much difference in the chemical composition of the soil with increased depth. Therefore, it seems [drilling] is not really necessary.”
The scoop can penetrate about an inch below the surface. “What’s really critical here is to take rocks,” says Zakharov. “Because the surface regolith was reprocessed many times, it is very possible it reflects the history of something other than Phobos itself.”
The robotic arm can collect rocks up to about half an inch in diameter. It ends in a pipe-shaped tool that splits to form a claw. This encloses a piston that will push the soil sample into an artillery-shell-shaped container. A light-sensitive photo-diode in the claw will help scientists confirm that the device did scoop material. They hope also to see images of trenches the claw leaves on the surface. The manipulator should perform 15 to 20 scoops yielding a total of three to five and a half ounces of soil.
“Nobody knows what Phobos’ soil is going to be like,” Zakharov says. “It might be perfect beach sand. But we hope—and something is whispering to us—that it will be a combination of sandy soil and small rocks.” IKI scientists studied images from the NEAR probe, which NASA landed on the asteroid 433 Eros in 2001, and concluded that the soil on Phobos may be similar. The team also created a model of Phobos’ soil, based on samples of Earth’s moon, and found that it likely sticks together well enough to stay inside the claw during the transfer to the return container. “We hope that in the lack of gravity, this sticking effect will be even stronger,” says Zakharov.
The return rocket will sit atop the spacecraft, and will need to rise at 22 mph to escape Phobos’ gravity. To protect experiments remaining on the lander, springs will vault the rocket to a safe height, at which its engines will fire and begin maneuvers for the eventual trip to Earth.
The lander’s experiments will continue in-situ on Phobos’ surface for a year. To conserve power, mission control will turn these on and off in a precise sequence. The robotic arm will place more samples in a chamber that will heat it and analyze its spectrum. This analysis might determine the presence of easily vaporized substances, such as water.
In addition to its promised scientific harvest, Phobos-Grunt is rejuvenating old alliances between Russian scientists and their colleagues abroad. Such cooperation reached its finest hour in 1984, when the Soviet Union launched the Vega 1 and 2 probes to Venus. By releasing balloons into that planet’s atmosphere and a flyby of Halley’s Comet, Vega returned volumes of scientific data, forging worldwide scientific cooperation. The spacecraft carried science payloads produced in more than half a dozen countries, and the comet approach included a flotilla of probes from Japan and Europe.
“After this mission,” Linkin remembers, “there was an impression that we can achieve so much through cooperation.”
Unfortunately, the success was followed by one failed and one only marginally successful mission to Phobos, plus the fiasco of Mars-96, which deprived scientists around the world of data and research, and eroded their decade-long trust of the Russians. “There was an emotional aftermath from the Mars-96 failure,” Linkin says. “Everything always fails on your side,” his foreign colleagues complained to him.
But these scientists are connecting again. In December 2005, the French and the Russians started discussing cooperation on Phobos-Grunt. Before long, French instruments were on board.
Then, in 2006, the Russians announced that the Chinese would add a 243-pound spacecraft, Yinghuo-1, to Phobos-Grunt to study Mars’ atmosphere. This maxed out the capabilities of the planned Soyuz rocket and required a switch to a more powerful and expensive Zenit booster.
Others are piggybacking too. Perhaps the most unusual passenger on Phobos-Grunt comes from the U.S.-based Planetary Society. Its Living Interplanetary Flight Experiment, or LIFE, will send 10 types of microorganisms and a natural soil colony of microbes on the three-year round trip. “This would be the first time live organisms take an interplanetary flight”—on a controlled experiment, at least—says Louis Friedman, the society’s executive director. The results may fuel the debate about whether meteorite-riding organisms can spread life throughout the solar system.
Some fear that the eight-ton Phobos-Grunt—expected to carry up to 20 experiments—has ballooned into a Noah’s Ark of science. Friedman advises having a little patience with the Russians’ approach. “We might find it strange,” he says, “but their philosophy is, if the new task is not affecting the main goal of the mission, it can be added. They take all these changes much more easily than we do. In the ’80s they were planning to drop balloons in the atmosphere of Venus. Then they decided to take the same spacecraft to Halley’s Comet almost at the last minute, and they did it successfully.”
Others are less certain. “The Phobos-Grunt mission is very ambitious,” says CNES’s Rocard, “and I think the Russians are not very confident in their own technology. They are not sure they could actually bring back the samples. That is why they want some scientific return by remote-sensing Mars, or in-situ experiments on Phobos.” He speculates that a hidden rationale for Phobos-Grunt’s broad nature is winning support within the Russian scientific establishment. “This is an internal problem in Russia. If they make too narrow a selection [of experiments], there will always be scientists who are not happy. They would keep criticizing the mission. My feeling is 20 instruments are too much. In the U.S. they put six instruments [on a typical planetary probe].”
A major milestone comes at the beginning of next year, when IKI is scheduled to deliver the science instruments for installation on the spacecraft.
“We have a good chance that Phobos-Grunt will fly,” says Zelenyi of the 2009 launch date. He adds that Phobos-Grunt could still go to Mars with its full payload in 2011. That year, the planet’s orbit won’t synch with Earth’s the way it will in 2009, so the mission would require the more powerful Zenit. “It would not be a tragedy,” he says.
Successful or not, Phobos-Grunt will pave the way for a caravan of Russian probes to Mars and other planets, Russian space officials insist. But a success would boost the nation’s planetary science program and its standing in the world. Russian scientists know that very well. They took this gamble before.
For updates on the status of Phobos-Grunt, visit the author's website at RussianSpaceWeb.com.