Few Details in ESA’s Report on Phobos-Grunt Re-Entry

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A week and a half after the re-entry of Russia’s Phobos–Grunt probe, experts have now made an official statement on their determination of where the spacecraft entered Earth’s atmosphere. But their report offers no information regarding if any pieces of the craft made it to Earth and where any remaining debris might be. Consequently, recovery of any pieces, including the Phobos-LIFE biomodule is highly unlikely.

“While this was an uncontrolled reentry, the location of the potential impact area was largely over ocean, with a correspondingly low probability of any detrimental effects,” said Prof. Heiner Klinkrad, Head of ESA’s Space Debris Office in Darmstadt, Germany.

The Inter-Agency Space Debris Coordination Committee (IADC) reports that Phobos–Grunt re-entered on January 15, 2012 at 17:46 GMT, at an altitude of 80 km at 46°S and 87°W, near the South American coastline. About 7 minutes later, the report says, the spacecraft’s altitude was 10 km.

“Within the expected uncertainties, the prediction has been largely confirmed by observations,” ESA’s press release stated.

And that is all the information the IADC has provided, with no details on whether those observations were from observers on the ground or from satellite and radar facilities.

In fact, most of the initial information verifying that Phobos-Grunt was no longer in orbit came from ground observations of not seeing the spacecraft in orbit over Europe after 18:00 UTC on January 15 when it was supposed to have a visible pass.

IADC members include NASA, Roscosmos, the European Space Agency, European national agencies and the space agencies of Canada, China, India, Japan and Ukraine. The group primarily used orbit data from the U.S. Space Surveillance Network and the Russian Space Surveillance System to determine Phobos-Grunt’s path to destruction. Radar systems in Germany and France also provided orbit calculations.

Phobos-Grunt orbiter and lander. Credit: ESA

Before re-entry, predictions from the various agencies differed widely, and initially after the probe was said to have re-entered, there was confusion on when and where the re-entry took place. Roscosmos initially released a statement claiming that the probe had fallen safely in the Pacific, off the coast of Chile, but later there were reports that fragments of the spacecraft had fallen in the south Atlantic Ocean. Officials said the confusion was due to the large number of uncertainties in the spacecraft’s orbit and the space environment affecting the satellite.

Indeed, everyone involved in re-entry calculations acknowledges the problematic nature of trying to monitor things in real-time, such as atmospheric density in the specific location the object is traveling. Most of the time, the details can only be deduced after the time of re-entry, and any unknowns can alter the projected re-entry and impact point by wide margins.

And so it is not entirely surprising that the IADC cannot offer much information beyond the initial entry point and time for Phobos-Grunt.

Although much of the Phobos-Grunt spacecraft was expected to disintegrate upon re-entry, Roscosmos said perhaps 20 to 30 fragments weighing a combined 200 kg (440 lb.) might survive and fall somewhere over a vast strip of the Earth’s surface between 51.4 deg. north and south of the equator.

The cause of the spacecraft’s malfunction has not yet been determined, and Roscosmos has indicated that a full report on the failure will be published on January 26, 2012, although an interim report said to be available by January 20 did not appear. The investigation is being conducted by Yuri Koptev, former head of the Russian Space Agency.

Shortly after launching from the Baikonur Cosmodrome on Nov. 9, 2011, the probe became stuck in low Earth orbit after its upper stage engines repeatedly failed to ignite to send the ship on an unprecedented sample return mission to Mars’ moon Phobos. Later, ESA tracking stations were instrumental in establishing short-lived contact with the probe, leading to hopes the spacecraft could be saved. But subsequent contact was not able to be made, and without contact and inputs from the ground, the spacecraft’s orbit disintegrated.

However, the story of Phobos-Grunt’s malfunctions and demise has included some wild claims ranging from accidental radar interference to outright sabotage, along with intimations of conspiracy theories.

Several times after the malfunction, Russian space officials suggested that US radar emissions may have accidently disabled the spacecraft; at first from a station in Alaska, and then — after it was pointed out that Phobos-Grunt had never flown over that location — another Russian official said it was perhaps radar from a military installation on Kwajalein Atoll in the Marshall Islands.

But these claims were later dismissed by a Russian scientist, Alexander Zakharov from the Russian Academy of Science Space Research Institute, who was involved with the development of Phobos-Grunt. He told the Russian news agency Ria Novosti that the radar theory is “far-fetched,” and suggested instead that issues with the spacecraft itself were likely to blame.

“You can come up with a lot of exotic reasons,” Zakharov told RIA Novosti. “But first you need to look at the apparatus itself. There are problems there,” and he indicated there may have been some known problems with the second stage of the rocket.

Later, after re-entry, links to Phobos-Grunt tracking data on the Space Track website were removed, fueling speculation of a conspiracy to hide in formation of where the probe fell. Space Track is a public website that ordinarily details such events, and is operated by U.S. Strategic Command. The military also did not publish any confirmation of the probe’s fall, which is not the usual protocol.

But later, the US Strategic Command said a human error had accidentally misfiled the information (in the 2011 files instead of 2012). Shortly after the error was discovered, the information was re-posted to the site and is accessible at this time.

The Planetary Society’s Living Interplanetary Flight Experiment (LIFE) capsule, on board the Phobos-Grunt spacecraft. Credit:The Planetary Society

Meanwhile, hopes dim for finding the capsule for the Phobos-LIFE biomodule which included organisms in a small capsule to test the “transpermia” hypothesis –- the possibility that life can travel from planet to planet inside rocks blasted off one planetary surface by impact, to land on another planetary surface. The biomodule would have flown to Phobos and then returned to Earth with the sample return capsule of the Phobos-Grunt spacecraft.

“Because we can’t predict the details of the re-entry, we can’t predict whether the Phobos LIFE biomodule will survive, and certainly we can’t predict whether it will land somewhere it could be recovered,” said Bruce Betts from The Planetary Society, which sponsored the LIFE mission. “In the unlikely event the Phobos LIFE biomodule is recovered, we would want to study the organisms inside. Though not the long deep space experience we had hoped for, there still will be scientific value to study of the organisms even after just two months in low Earth orbit.”

Sources: ESA, ZaryaInfo.com, ieeeSpectrum/Jim Oberg, Ria Novosti. Special thanks to Robert Christy for the lead image, from his website Zarya.info

Contact Established with Phobos-Grunt Spacecraft — Can the Mission Go On?

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Editor’s note: Dr. David Warmflash, principal science lead for the US team from the LIFE experiment on board the Phobos-Grunt spacecraft, provides an update on the mission for Universe Today.

In an exciting development in the ongoing story of the Phobos-Grunt mission, a tracking station at Perth, Australia established contact with the Russian spacecraft on November 22 at 20:25 UT. This was the first signal received on Earth since the mission to Mars’ moon was launched on November 8, 2011.

Teams from ESA, who made the initial contact, are now working closely with engineers in Russia to determine how best to maintain communications with the spacecraft. As controllers begin the task of figuring out how to use this achievement to enable sending the spacecraft new commands, discussion is ongoing on whether the launch window will still be open for the craft to complete the mission.

The hopes are now is that at the very least engineers can prevent the spacecraft from plummeting back to Earth – and with guarded optimism that the mission could proceed in some manner.


Before contact was made, some reports said that if contact was made by November 24, the mission could proceed as planned, while other experts were saying that the launch window to complete the sample return mission closed on November 21.

But yet, a mission leaving from Earth orbit well into December might still succeed.

Engineers tuck Phobos-Grunt into the rocket fairing. Credit: Roscosmos

Built to travel to Phobos, the larger of Mars’ two moons, the centerpiece of the unmanned spacecraft is a small capsule in which 200 grams of regolith (surface material consisting of dust and crushed rock) is to make a return flight to Earth. To launch the capsule on a flight that would return it to Earth in 2014, the spacecraft was scheduled to land on Phobos in February 2013 after entering orbit around Mars in October 2012.

A launch window is a period during which travel from one celestial body to another is possible, given a spacecraft’s propulsion capabilities and the alignment of the celestial bodies as they move through space. In the future, advanced propulsion technologies could allow for trips between Earth and Mars to depart at any time, but for now spacecraft must wait for the optimal moment. For trajectories from Earth to Mars, launch windows occur roughly every 26 months, as do launch windows for inbound flights to Earth from Mars.

The launch window for an Earth-to-Mars trajectory actually would allow Grunt to reach Mars and Phobos, if the spacecraft is readied for departure within two or three weeks from today. In such a case, however, the collection of regolith on the Phobosian surface would take place after that window has closed for the capsule to launch back to Earth. This is why people are saying that the window for Phobos-Grunt will close this Thursday.

But, as stated earlier, the window could still be open through mid-December. To see why, let’s take a glimpse of the Grunt’s science payload and other components . Sitting in front of what the Russian Space Agency is calling the sustainer engine, whose job is to propel the spacecraft from Earth to Mars, is a 110 kilogram probe called Yinhuo-1. China’s first Mars probe, Yinhuo-1 is to orbit the Red Planet for two years, performing various scientific studies. Moving forward from Yinhuo-1, brings us to the interplanetary module, Grunt’s descent stage.

Costing 5 billion rubles, or about 160 million US dollars, the interplanetary module is equipped with a descent engine and legs for landing on the Martian moon, machinery for scooping the regolith sample, and about 50 kilograms of extremely advanced scientific equipment whose value to the mission does not depend on whether the regolith sample makes it back to Earth.

Finally, there is the ascent stage and the return capsule that will lift off with it for the flight to Earth. In addition to accommodating the regolith that will be deposited inside, the capsule holds the Planetary Society’s LIFE biomodule, a study of the effects of the interplanetary space environment on organisms during a long-term voyage through space.

Before and after the departure of the return capsule, the instruments of the interplanetary module will be at work, performing celestial measurements, studying solar wind, and conducting geophysical studies -experiments whose results will help planetary scientists to understand the origin of our Solar System. The science package also will perform elemental, chemical, mineralogical, and thermal analysis of the regolith, look for traces of gases from Mars, and search for organic matter, the stuff of life.

ESA's Perth station, which made contact with the Phobos-Grunt spacecraft, is located 20 kilometres north of Perth, Australia. Credit: ESA

If Grunt were to make a one-way trip to Phobos, all of these studies could be performed, while Yinghuo-1 could be deployed around Mars, as is supposed to happen during a round-trip voyage. If it were determined that the capsule really had no chance of making it from Phobos back to Earth, the capsule might even be jettisoned in high Earth orbit before the sustainer stage completes the final burn to escape Earth’s gravitational pull. This might return the LIFE biomodule to Earth after a long trajectory through deep space that would satisfy the objectives of the experiment. Then, we could recover our biomodule and study the organisms as planned.

On the other hand, controllers might consider sending the return capsule to Phobos despite the closure of the launch window for a return flight. After landing on the Martian moon atop the interplanetary module, the ascent stage need only wait until the next launch window opens 26 months later for arrival on Earth in 2016.

The contact now made with the spacecraft may open up even more possibilities for saving the mission. ESA said in a press release that the signals sent to Phoboos-Grunt commanded the spacecraft’s transmitter to switch on, sending a signal down to the station’s 15 m dish antenna.

Data received from Phobos-Grunt were then transmitted from Perth to Russian mission controllers via ESA’s Space Operations Centre, Darmstadt, Germany, for analysis.

Additional communication slots are available on November 23 at 20:21–20:28 GMT and 21:53–22:03 GMT, and ESA teams are working closely with Russian controllers to determine how best to maintain communication with their spacecraft.

See the ESA press release here.

Can Phobos-Grunt Still be Saved? Scientists Hold Out Hope as Deadlines Loom

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Editor’s note: Dr. David Warmflash, principal science lead for the US team from the LIFE experiment on board the Phobos-Grunt spacecraft, provides an update for Universe Today on the likelihood of saving the mission.

Although the launch window for a round-trip to Mars closed yesterday (November 21, 2011) with Russia’s Phobos-Grunt probe still circling in low Earth orbit, a one-way flight to the Red Planet will be possible for another few weeks. As Russian engineers frantically try to contact the silent probe, scientists from the Yinghuo-1 and LIFE experiments are holding out hope that they could still complete their missions, or a perhaps even a modified version of their experiments.

Launched November 9 to collect a surface sample from the larger of Mars’ two moons, Phobos, the 13-ton spacecraft was to be boosted from its initial parking orbit low in Earth’s skies within hours after reaching space, when the engine of its Fregat upper stage failed to ignite. Thought to have reverted to safe mode, Phobos-Grunt has been flying straight and periodically adjusting her orbit using small thruster engines. While this maneuvering has extended the amount of time that the probe can remain in space before reentering Earth’s atmosphere, ground controllers have been struggling to establish a communication link.

The Phobos-Grunt mission profile. Credit: Roscosmos

Had the malfunction occurred just one step further into the flight –after a first burn of the Fregat was to raise the apogee (the highest point) of the spacecraft’s orbit to an altitude of about 4,170 kilometers– the timing and geometry between Earth-bound transmitters and the spacecrafts antennae would have made signaling the craft a straight forward task. But with Grunt orbiting much lower (thus moving much faster with respect to the ground), and with an antenna that could receive the signal obstructed partially by a fuel tank that was to be jettisoned after the first Fregat burn, controllers have only a couple of minutes at a time to attempt communication. Since the spacecraft was not designed for this scenario, getting her attention may be depend on prospect of getting the signals toward her at some unlikely angle. In other words, restoring control over Phobos-Grunt may be a matter of luck.

But if luck is a factor in recovering the spacecraft, then the extension of her expected time in orbit due to thruster firings may prove helpful. The more time that controllers have to attempt contact, the better the chances that they’ll get lucky at some point before the craft reenters the atmosphere.

If this should happen, however, where should the probe travel? As of yesterday, it no longer will be able to go Mars, land on the surface of Phobos, scoop a 200 gram sample into the specially-designed return capsule, and still have a window for the capsule to be launched on a trajectory back to Earth. Last week, a lunar mission was discussed as a possibility.

But as a story released yesterday by the Russian news service Ria Novosti notes, the launch window to Mars for a craft that does not need to return to Earth remains open. In the case of NASA’s Mars Science Laboratory with its rover “Curiosity,” for example, the launch window to Mars is open until December 18.

This means that –if communication with Grunt is established– the Phobos-Grunt could be launched on a trajectory to Mars. This would not support the objective of return a sample from the Phobosian surface. However, since China’s Yinghuo-1 probe is piggybacked on the spacecraft for delivery into orbit around Mars, its mission at least would not be affected by the lack of a return flight.

The Planetary Society’s Living Interplanetary Flight Experiment (LIFE) capsule, on board the Phobos-Grunt spacecraft. Credit:The Planetary Society

Then, there is the Planetary Society’s Phobos-LIFE. The objective of this project is to study the effects of the interplanetary environment on various organisms during a long duration flight in space beyond the Van Allen Radiation Belts, which protect organisms in low Earth orbit from some of the most powerful components of space radiation. If the biomodule containing the LIFE organisms travels one way to Mars, it will not help the experiment. But it may be possible to jettison the return capsule when the spacecraft is in a high orbit around Earth, before the final burn sending it toward Mars has been completed. If this happens, the return capsule –which would not be needed anyway for a one-way Mars mission– might be set on a trajectory that takes it beyond the Van Allen belts for many months, or longer, but that eventually takes it back to Earth. If so –and as usual, I emphasize the “IF” – the capsule could make the reentry and landing that it was designed to do, we could recover our biomodule and study the organisms as planned.

Phobos-Grunt’s Mysterious Thruster Activation: A Function of Safe Mode or Just Good Luck?

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Editor’s note: Dr. David Warmflash, principal science lead for the US team from the LIFE experiment on board the Phobos-Grunt spacecraft, provides an update for Universe Today on the likelihood of saving the mission.

The Phobos-Grunt probe is still stuck in orbit around Earth. However, periodically the spacecraft experiences a mysterious slight boost in its orbit.  Following the first episode where this occurred, commentators speculated as to the cause.  The activation of the spacecraft’s thrusters – the small engines that are designed to steer the craft and make small adjustments  — was an obvious answer.

Is spacecraft trying to save itself?

The spacecraft is not responding to any communications, and engineers at the Russian Space Agency Roscosmos have decided that the craft had reverted to a safe mode after the engine of the Fregat rocket stage that was to propel her from a low to a higher orbit around Earth failed to ignite. While in safe mode, the craft had oriented herself to the Sun, using the thrusters to adjust her roll, pitch, and yaw. But to change the parameters of the orbit, she’d need to accelerate, so there was speculation that the needed thrust had come from leaks and venting of gases in a direction favorable to increased orbital stability.

After a second episode during which the altitude increased again, according to Ria Novosti editor-columnist of the journal “News of Cosmonautics” Igor Lisov has reported that a source in the space industry had explained that the probe “Corrects her orbit” every now and then.

Corrects her orbit? Does this mean that the probe knows where she is?

Probably not.

With information coming from Roscosmos being so scarce, reporting on the mission that began was launched on November 9, 2011 has depended on a few official statements from the agency, augmented by speculation from various space experts. Being in safe mode, Grunt simply is waiting for instructions –instructions that controllers are having difficulty delivering, because initial communication was not supposed to take place with the probe at such a low orbit.

If Grunt’s safe mode includes a program that fires thrusters every so often to keep the craft from entering the atmosphere in the event of a malfunction just after reaching low Earth orbit, no statements from Roscosmos have mentioned it, thus far. Whatever the reason, if it continues to occur, we can expect that the predicted date of atmospheric entry will be moved back again, just as it was moved from late December/early November to mid-January after the first orbital correction episode.

The Planetary Society’s Living Interplanetary Flight Experiment (LIFE) capsule, on board the Phobos-Grunt spacecraft. Credit:The Planetary Society

What might this mean for the mission? First of all, perhaps it could buy more time for controllers to establish communication –although Roscosmos has stated that December is the limit for correcting the problem, despite the fact that the probe will be in space at least until mid January. The second thing it could do would be to keep the Planetary Society’s LIFE experiment in space a little longer, which would have benefits only if the Grunt return capsule containing the LIFE biomodule separates from the rest of the craft and makes the reentry and landing that it was designed to do at the end of the flight. This possibility and the potential scientific value is discussed in my previous update, Might the LIFE Experiment be Recovered?

As for the question of why a craft that merely is supposed to find the Sun while in safe mode fires thrusters in a direction that improves the orbit, perhaps it is just good luck, or perhaps it really is part of the safe mode. Until Roscosmos provides more information of what may have caused this, the reason for the orbital correction remains a mystery.

Update on Phobos-Grunt: Might the LIFE Experiment be Recovered?

Phobos-Grunt

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Editor’s note: With Russian engineers trying to save the Phobos-Grunt mission, Dr. David Warmflash, principal science lead for the US team from the LIFE experiment on board the spacecraft, provides an update of the likelihood of saving the mission, while offering the intriguing prospect that their experiment could possibly be recovered, even if the mission fails.

With the latest word from Roscosmos being that the Mars moon probe, Phobos-Grunt is “not officially lost,” but yet remains trapped in low Earth orbit, people are wondering what may happen over the next several weeks. Carried into space early Wednesday morning, November 9, Moscow time, atop a Zenit 2 rocket, Grunt, Russian for “soil”, entered what is known in space exploration as a parking orbit. After the engine of the Zenit upper stage completed its burn, it separated from another stage, known as Fregat, which now still remains attached to Phobos-Grunt. Ignition of the Fregat engine was to occur twice during the first five hours in space. The first Fregat burn would have taken the spacecraft to a much higher orbit; the second burn, about 2.5 hours later would have propelled the probe on its way to Mars and its larger moon, Phobos. From this moon, a sample of soil would be scooped into a special capsule which would return to Earth for recovery in 2014.

Grunt is still in a low orbit, because neither Fregat burn occurred. While the spacecraft is believed to be in safe mode and even has maneuvered such that its orbital altitude has increased, controllers have been unable to establish contact to send new commands. If communication cannot be established, it will re-enter the atmosphere.

In addition to the sample return capsule, Grunt carries an instrument package designated to remain on the Phobosian surface, plus a Chinese probe, Yinghuo-1, designed to orbit Mars. The mission also includes the Planetary Society’s Living Interplanetary Flight Experiment (LIFE) , for which I serve as principal science lead of the US team. Carried inside the return capsule into which the Phobosian soil is to be deposited, LIFE consists of a discoid-shaped canister, a biomodule, weighing only 88 grams. Inside are 30 sample tubes carrying ten biological species, each in triplicate. Surrounded by the 30 tubes is a sample of soil with a mixed population of microorganisms, taken from the Negev desert in Israel to be analyzed by Russian microbiologists.

The Planetary Society’s Living Interplanetary Flight Experiment (LIFE) capsule, on board the Phobos-Grunt spacecraft. Credit:The Planetary Society

Organisms carried within the LIFE biomodule include members of all three domains of Earth life: bacteria, archaea, and eukaryota. The purpose of the experiment is to test how well the different species can endure the space environment, akin to microorganisms moving in space within a meteoroid ejected from Mars by an impact event. If organisms can remain viable within rock material that is transferred naturally from Mars to Earth, it would lend support to the Mars transpermia hypothesis –the idea that life on Earth may have began by way of a seeding event by early organisms from Mars.

We know of microorganisms that could survive the pressures and temperatures associated with the ejection itself. We also know that during atmospheric entry, only the most outer few millimeters of rocks are heated on their way to Earth; thus, anything alive in a rock’s interior at this point should still be alive when the rock hits Earth as a meteorite. If life forms also could survive the journey itself from Mars to Earth, a Martian origin for Earth’s life would be a major possibility. It also would mean that life originating on its own anywhere in the Cosmos could spread from each point of origin, thus increasing the number of living planets and moons that may exist.

Numerous studies of the survivability of many of the LIFE species have been conducted in low Earth orbit, but much of the challenge to life in space comes from highly energetic space radiation. A large portion of space radiation is trapped by a system of magnetic fields known as the Van Allen radiation belts, or the geomagnetosphere. Since very few controlled studies of microorganisms, plant seeds, and other life have been conducted beyond the Van Allen belts, which reach an altitude of about 60,000 kilometers (about 1/7th the distance to the Moon), the Planetary Society arranged to have the LIFE biomodule carried within Grunt’s return capsule.

Over last weekend, the spacecraft surprised everyone by maneuvering on its own, raising its orbit. Due to this, the estimated reentry date was moved back from late November to mid January, meaning that the LIFE biomodule will be in space for more than nine weeks. An intriguing possibility that looms as controllers consider how the mission might end is that the Grunt sample return capsule will break off from the rest of the craft intact. If this happens, it could assume the stable atmospheric entry, descent, and landing that were expected after the return from Phobos. If this happens and the capsule comes down on land, we could recover the LIFE biomodule and test the state of the organisms packaged within it. The result of yet another biological test in low orbit, it would not be the experiment of our dreams. But, amidst the loss of a mission into which so many engineers and scientists have invested their dreams, a little bit could mean a lot.