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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.
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.
Phobos-Grunt very safe for you. Breath smoke in air, re-entry good. Healthy public “nominal” chirp chirp…
I was wondering just how the Phobos reentry capsule was to be located at the end of the mission. From the russianspaceweb Phobos-Grunt page:
“The final critical aspect of the Phobos-Grunt mission would be the reentry of its capsule with soil samples into the Earth atmosphere in August 2014. From the outset, Russian developers decided not to rely on any active landing systems, such as radio-beacons, to locate and recover the tiny vehicle. They cited the mass limitations of the capsule and the dangers of relying on electronic gear, which would have to function flawlessly after a multi-year journey to the Martian orbit and back.”
“Instead, ground-based radar and optical observations would be the sole means of tracking the vehicle during reentry and of pinpointing the site of its touchdown. As a result, mission developers quietly chose the Sary Shagan test range in Kazakhstan as the primary landing site for the Phobos-Grunt mission. A birthplace of the Soviet anti-missile defense systems, Sary Shagan still serves as a key test base for Russian anti-missile interceptors and associated radar. After the end of the Cold War, the center retained some of the systems designed to detect high-velocity objects in the atmosphere and in near space.” [ http://www.russianspaceweb.com/phobos_grunt_scenario.html ]
So no location-beacons. I can see how an uncontrolled reentry of the entire vehicle would greatly complicate locating the reentry capsule, if it did manage to fall back to solid ground! Hopefully ground tracking can help narrow the likely impact zone some or enough control of the vehicle can be established to bring it down in a more controlled manner.
I really hope something like the Planetary Society’s experiment can be salvaged from this mission.
The bad news is that if Phobos-Grunt maneuvered outside of plan, it is now likely a failure. Unless it was the first orbit maneuver, raising the parking orbit.
[UPDATE: It is not quite as dire, it seems: the craft is orbiting too fast and near for “grunt” [sic!] stations to keep up and to transmit sufficiently low power. Despite what early reports says, it seems this scenario hasn’t been sufficiently planned for, and that they now scramble to contact a potentially healthy craft.]
At least it will make grunt (or water). :-/
A possibility, but likely not major.
If I remember correctly, the reason Mars-Earth transpermia was conceived was the then problem of finding fast enough pathways for abiogenesis. Mars, aggregating earlier, seemed like a good bet to extend the time period and increase the abiogenesis volume. We now believe Mars formed ~ 3 Ma after the protoplanetary disk originated (ado), while Earth may have formed ~ 30 Ma ado.
But another line of thinking has been a rapid abiogenesis. Miller concluded that his soup scenarios with free living proto-cellular systems (akin to Szostak’s lipid protocells) required, and could meet, the ~ 12 Ma average time before a volume of sea water is sterilized by circulating through a hydrothermal vent. I have often pointed to the new observations of likely early rapid biochemistry that may validate quick abiogenesis from a vast volume (essentially the whole surface, oceans and crust of a planet).
The success rate of that process would be balanced by the chain of abiogenesis, success rate of transpermia and transit time. The only observation of transit time I know of is ALH84001 at ~ 16 Ma, which is low enough.
So let us look at the Earth-Mars timeline.
– Mars formed ~ 30 Ma earlier than Earth, and with the quick scenarios it had life before Earth. Since we had a high rate of impactors, transpermia could have been successful and Earth could have been seeded by Mars.
That would happen at roughly the time the temperature lowered so that Mars protocells could survive among already happening Earth abiogenesis. If the Martian protocells could compete with Earth’s less mature ones is an iffy question, however. I would think Earth’s protocells were adapted to the local environment, and would make immigrants extinct. (See more below.)
– The sterilizing impact that formed the Earth-Moon system happened anytime from ~ 30 Ma ado (old isotope data) to ~ 180 Ma ado (new isotope data). Likely then the scenario would have to play all over again, now with more mature Mars protocells.
It comes down to how fast the Earth re-cooled. But we have evidence of a vast liquid water reservoir at ~ 190 Ma ado (4.35 Ga bp Jack Hill zircons). Maybe old hypotheses of ~ 10 Ma for Earth crust formation will have to be reopened.
LHB at ~ 350 – 750 Ma ado (4.2 – 3.8 Ga bp) seems survivable in new models. It is also consistent with gene family clock dates, see below.
Adding it up using the latest observations: it may be that we had ~ 180 Ma old martian protocells (~ 10 Ma transit time) trying to adapt to an environment where a vast and competing abiogenesis event happened.
Protocells would not adapt well, due to lack of a genetic system, so it seems unlikely that immigrants would make it, to take up and fill out the full extent of the adaptation problem mentioned above.
The earliest gene families may be from ~ 230 Ma ado (own estimate from the Archaean Expansion model of gene families). If ancestor protocells were of Earth origin, protocells would have evolved genes in ~ 40 Ma at most, a fairly reasonable period. If they were of Mars origin, they would have taken ~ 220 Ma to do so (less the transit time in deep frozen state), which seems exorbitantly long.
For these two reasons, problems of protocell adaptation and problems of these particular transpermia protocells acquiring a genetic system in the latest timeline (again pointing to adaptation problems), I think it is fairly safe to say Mars to Earth transpermia is a long shot.
That analysis is in part sensitive to observations that have yet to be adopted and reconciled. On the other hand, if you try smaller rates and longer times for abiogenesis and transpermia events you will run into problems of squaring with running the gamut of posited observations.
What does “Ma” mean?
Million Annum -> a million years.. I think.
Yes. Apparently it is the ISO standard for years. I gave up on the other symbols, since everyone used different definitions.
Sorry for the confusion, but I’m trying to keep a rein on my own…
Thanks for explaining the Ma term.
I agree with your comment. Panspermia would require so many chance occurences and so much time, I think it is a very long shot. To believe that a rock that contains life got smashed so hard it leaves Mars’ orbit, which alone would sterilize most things, then has to make a journey of millions of km across a dangerous vacuum (which could take hundreds, thousands or millions of years), to some how land on Earth and not be destroyed by the reentry or the crash and to land in a medium that would support that life’s regeneration is a big stretch of the imagination. Occums’ razor would suggest that this is by far the least likely option for life. Much more likely to originate on Earth.
Floating a bunch of microbes out in space for a few weeks or months is a far cry from the scenario I described above. I’m not sure that you can extrapolate from this experiment to conclude that our life came from Mars or anywhere else.
Usually I grin and grunt a bunch anyway.. but this grunt takes on special meaning. Akin to a groan…
Now, the LIFE experiment was to be in deep-space for a period of about 3 years. But the journey for a rock traveling from Mars to Earth may have taken tens or hundreds or thousands of years, thereby exposing any organisms in the rock to an amount of radiation far far more than what the microbes in the LIFE experiment would have been subjected to.
What is the “usefulness” of the data collected from this experiment then? If the microbes and water bears survive a 3 year trip in deep space, does that really tell us anything about transpermia?
You make a good point. It’s obviously not possible for the current generation to test the real travel time of millenia so we are doing the next best thing on a shoestring budget.
The experiment still does tell us a lot about transpermia because if the organisms survive then we at least have a PLAUSIBLE stamp (ala mythbusters) on the hypothesis. If it FAILS and the organisms can’t even make it 3 years, then maybe we have an early data point against transpermia.
I find it interesting that when people talk about panspermia they always say “life on Earth may have started from Mars” but I would think the reverse is also likely.
The LIFE experiment is silly and dangerous. It can teach us nothing (we already know that dormant microorganisms can survive in the conditions of space for short periods, and it says nothing about long term survival in an asteroid), but what it could have done was contaminate the surface of Mars if the probe crashed. In fact, it’s hard to see what the purpose of sending samples with unknown content like “soil from the negev desert” is EXCEPT to contaminate. I find it surprising that NASA’s office of planetary protection greenlighted the LIFE experiment, and am frankly happy that the probe failed now instead of at Mars.