In early February, looming from the top of a grassy hill, the dingy-brown building of the Carnegie Institution’s Geophysical Laboratory is Chevy Chase Heights’ very own House of Usher. Smack in the middle of a residential neighborhood, the wooden entrance sign appears abruptly at the bottom of the hill, just 20 feet from a pile of logs and tree stumps. A gray hooded sweatshirt hangs forgotten from one naked magnolia. The grass of the grassy hill is dead, and crunches when you trudge through it. One hundred and fifty of the nation’s best scientists work here, but only a handful of cars are parked along the edge of the driveway that winds up sharply to the front door. You can hear the slow punch of the buttons when the elderly secretary enters the door’s security code, and even the soft shuffle of her shoes on linoleum as she escorts you down the empty corridor. Desolate, cold, a vestige of past greatness—in short, it’s everything you might expect from a martian-life-detection lab.
The idea of martian life detection was challenged in 1996, when the young Brit Andrew Steele showed that meteorite ALH84001—though maybe also harboring martian life—was certainly contaminated with Antarctic bugs. But even after undercutting NASA’s triumphant find, Steele still believed we might one day find life on the Red Planet. Today
, he’s focused on making life-detecting instruments for both rover and manned missions to Mars, in a few of the microbiology labs of the creepy building on the hill.
Though a decade has passed since he trumped NASA’s claim, Steele still looks like a grungy twenty-something. He’s tall, lean, and slightly apish. His wavy blonde hair covers the letters printed on the back of his t-shirt, so you can’t quite read the name of the garage band that’s printed on it; his blue jeans are so faded they’re white. He’s dirty, but wears jewelry—rainbow bracelets on his wrist and a heavy Celtic cross around his neck. He walks lightly on old green sneakers. They’re probably the same ones he had in August, when he traveled to the other side of the world to test his gadgets. But the Arctic Circle is way too cold for t-shirts.
In August of 2003, 2004, and 2005, Steele and his colleagues went to the Norwegian island of Svalbard. Svalbard is not only very cold—dropping down to -12 degrees Celsius, even in August, when there’s 24 hours of daylight—but dusty, and dangerous. (His crew, armed with shotguns, had to switch between crushing up rock and watching for polar bears.) The island is the only place on Earth with a volcano made up of the same kind of rock that was sampled on the Viking missions. And most important, the volcano harbors microorganisms that Steele’s gadgets can try to detect.
The gadgets are called microarrays, matchbook-sized glass chips loaded with different kinds of antibodies. Each antibody recognizes life-specific molecules in a rock sample, like nucleotides (the building blocks of DNA), amino acids, proteins, or certain carbon isotopes, and glows when it finds them. Once all of the kinks are sorted out, Steele says the chips will be used on NASA’s next big rover project, the 2009 Mars Science Laboratory. The MSL, part of NASA’s larger Mars Exploration Program, plans to send a huge, nuclear-powered rover to Mars. In their two years of exploring, the six-wheeled, the golf-cart sized Spirit and Opportunity rovers have each traveled about three miles. The MSL is a tank by comparison; it will travel up to 90 miles per hour, roll over obstacles 30 inches high, and will have a full on-board laboratory for testing climate changes and geological samples.
But to gain a true understanding of the landscape and really probe for life, Steele says, you need men. “Rovers are pretty easy now, we could send rovers all over the place for about $900 million a shot,” he says. “But a human being is a thousand times more capable than any robot.” Rovers have to stay on a fairly horizontal plane, for instance, so they often don’t have the right visual perspective to find subtle-yet-important geological features (like bedrock). Also, their controllers on earth can’t manipulate them in real time; they’re eight minutes behind. But the biggest problem, according to Steele, is that they don’t have object recognition. “An elephant could run in front of it,” he says, “and it wouldn’t know the difference.”
To make his point, Steele cites one rover story NASA hasn’t yet released. A few months ago, a wire broke on Spirit’s arm. “So the engineers spent a few days fixing it, slowly working the arm to loosen the dust they thought got into the motors,” he explains, “and meanwhile, the scientists had nothing to do.” Since Spirit was immobile for a few days, the scientists decided to take high-resolution photographs of the landscape, instead of the usual low-resolution ones. And the result was amazing: Steele says the new photos gave them incredible detail of the surrounding geological features. “They said, ‘oh my god, those crossbeds are fantastic. This is just brilliant,’ but normally, the rovers would never have caught all of that detail. A human would have seen it right away.” And the detail, in this case, was crucial: “it was evidence,” Steele says, “of water-induced features in the rocks.”
So in addition to tweaking the rover machines, Steele’s also working on what he calls the next generation of gadgets: those that would help
astronauts explore the planet. “We’re making computing technology—like GPS and camera systems, and a barcode system that automatically labels samples,” he explains. This would have been nice during the Apollo missions because, as Steele says “the geezers don’t have time to get everything, on the moon they often forgot to record locations and label properly.” But with the new toys, he says, “the astronaut merely needs to bag it, tag it, and the rest is done.”
This emphasis on helping astronauts do their job spurs Steele to visit extreme environments like Svalbard over and over again. He plans to go back for the next three Augusts, until the MSL is launched. “It’s good for the scientists to think they’re on Mars. You think: where is my next meal coming from? It makes you realize you have to make the science as easy as possible for the astronauts, because they’ve got to concentrate on staying alive.”
But will American astronauts ever land on Mars? On January 14, 2004, following reports of the success of Spirit and Opportunity, President Bush made a speech outlining his new “Vision for Space Exploration.” Reminiscent of Kennedy’s 10-year moon challenge in 1960, Bush proclaimed that rovers were necessary, at first, to serve as “trailblazers,” and “the advance guard to the unknown.” But ultimately, he said, we need to go the next step:
“…the human thirst for knowledge ultimately cannot be satisfied by even the most vivid pictures or the most detailed measurements. We need to see and examine and touch for ourselves…”His exact plan called for the development of a new spacecraft, called the Crew Exploration Vehicle, by 2008, with plans to have the first manned mission no later than 2014. The Crew Exploration Vehicle (which NASA Administrator Michael Griffin pegged “Apollo on steroids”) will be a cone-shaped capsule that can carry three men to the International Space Station, four to the Moon, and six to Mars. Bush said the main purpose of the Crew project is to take astronauts beyond our orbit, “to other worlds.” Yet despite the hype of this announcement, Steele says the new plan has actually “crippled science” at NASA, because it has diverted so many funds away from those astrobiology groups “whose labs aren’t absolutely aligned with Crew.”
One such group is led by Iain Neill Reid, an astronomer at NASA’s Space Telescope Science Institute in Baltimore (the birthplace of the Hubble telescope). Though he had been focused on studying dwarf stars for many years, in 2003, Reid switched gears. “A few of us here just started looking at how we could work in Astrobiology,” he says, “partly because the emphasis was switching at NASA, but also because at that time there was a lot of effort going into thinking about the Terrestrial Planet Finder.”
The Terrestrial Planet Finder (TPF) program, conceived by the brains at NASA’s Jet Propulsion Laboratory, is new. It was only in 1995, after all, that astronomers used high-power telescopes to discover that solar systems besides our own even exist. Since then, astronomers have found over 100 planets orbiting other stars. But the idea of TPF is to look not just for any ol’ planet, but for planets like earth—i.e., habitable ones. Reid says the basic idea of TPF is to use two complementary “observatories” floating in space: a coronagraph, observing visible wavelengths, and an interferometer for infrared wavelengths. A planet like the earth, he says, is about 100 million times fainter than its star. You use the coronagraph to block the light from the star and make the planet more visible. The interferometer, meanwhile, does the same kind of eclipsing, but in a slightly different way, called
nulling out. “Essentially you’ve got two wave patterns from the light from the central star,” Reid explains, “and if you combine them in the right way they’ll cancel each other out.” Here’s the connection to Biology: If an astronomer finds a planet-like object circling a star, Reid says, “we could kind of tell the microbiologists ‘here’s what the conditions might be like,’ and they could tell us what could live there.”
So in 2003, Reid joined Frank Robb and a few other extremophile experts at the Center of Marine Biotechnology and submitted a proposal to the NASA Astrobiology Institute (NAI). “Our idea,” he says, “was to look at the galaxy as a whole, and ask if there are particular places in the galaxy that are more favored to life than others.” But the NAI Committee at the time, Reid recalls, said “well, this is really too ambitious, and we don’t think you can do it.” So for the next couple of years, they funded what they could themselves. “We had a small amount of research money here at Space Telescope, only like 50 or 60K, but it was enough to pay for a grad student and get equipment.” The shoestring operation was the basis of the proposal they submitted a couple of years later, in the next round of NAI applications.
In October of last year, Reid and Robb joined with more scientists from Princeton and the Carnegie Institution to refine their TPF-like project, and create a scaled-back version of what they had proposed the first time around. “We said we’ll just look at the solar neighborhood, and try and essentially put together a kind of stellar encyclopedia of all the stars within 25 parsecs of the sun,” Reid says, “We want to try and figure out, if you’re thinking about finding life, which ones would be the best to look at.”
At the same time, one member of the Carnegie group, Maggie Turnbull, took on a related project of particular interest to Reid: Earthshine. When light from the Sun hits the Moon and then reflects to earth, we seen Moonshine, and it’s usually very bright. Similarly, when light from the Sun hits the earth, is reflected onto the Moon, and then reflected back to the earth, we see Earthshine. Because some light gets absorbed at each reflecting surface, Earthshine is much dimmer than Moonshine, and we can only see Earthshine during certain Moon phases—like young crescents—when Moonshine is especially faint. If you observe the light of Earthshine, Reid says, you’re effectively seeing features of the earth. “Suppose you were an alien from another planet,” he further explains, “and you get this spectrum. The question then becomes, can you tell from the spectrum if there’s life on earth?” As Turnbull is finding out, Earthshine shows you certain atmospheric features in the earth, like the presence of oxygen, or the chlorophyll produced by plants. By observing the Earthshine spectrum at different points of the earth’s rotation—that is, by taking a telescope around the world and observing the Moon from different places—Turnbull wanted to map how the spectrum changes based on the predominant landscape. As Reid explains, “you can tell if most of light that hits the moon is coming from oceans or deserts,” Reid says. “And then, you need to take the next step: If I look at the light distribution from some other planet, how do I
know if there’s life there?”
Finding life on other planets using Earthshine means comparing the earth’s light spectrum to that of planets that have yet to be discovered. “It’s planning way into the future,” Neil admits, “but certainly you want to be able to build the right kind of instrument to do this work.” When TPF is finished, for instance, Reid points out that there will be a giant telescope, four or five meters across, launched into orbit to take data. He says some fundamental questions—like whether it would be better to look in optical wavelengths or infrared—must obviously b e sorted out before a single data point is recorded. “If you take this thing and shove it up there into orbit,” he says, “you really don’t want to have to go up and monkey around with it afterwards.”
Steele’s life-detection chips, Reid’s terrestrial-planet-finding telescopes, Turnbull’s Earthshine spectra—it all began, and continued, on the promise of financial support from Uncle Sam. But on February 6, 2006, almost two years to the day after the announcement of his Vision for Space Exploration, President Bush proposed a new $2.77 trillion budget plan calling for increased spending on the military and domestic security and substantial cuts in domestic programs, including NASA. “Astrobiology seems to have been cut by 50 percent,” Neill says. “So it's pretty much what we expected, although a bigger cut than Andrew had been expecting. We'll just have to persevere as best we can for the moment and see whether the wind will change again.”
Despite the large NASA cuts, Steele’s lab isn’t likely to shut down soon. “We’ve already been funded by Astrobiology Instrument Department for developing instruments until 2009, .so we’ve got another three years,” Steele says. And if they don’t fund him after that, Reid says Steele’s work is important enough to find sources outside of the Astrobiology Institute. “But it doesn’t make it any better,” Reid laments. “It means that you’re going to have to go back and scramble to get other funding and meanwhile the people that you’ve assembled, they’re not just going to hang around there and wait in the optimistic hope, on the off chance that you’re going to get funded again. It’s wrenching, but it’s just the way it works.”
Assuming he finds a way to carry on his work, so what if Steele’s instruments—either by rover or man—do find life on Mars? Steele responds, “If we find it—fantastic! Brilliant! Superb! Let’s go get it, let’s study the hell out of it, let’s classify it. But I’m actually more interested in if we
don’t find life on Mars, and then why there isn’t life there. What went wrong? For me, that’s the biggest reason for going.”
If life was found on Mars, would the earthlings in charge
then put more funding into Astrobiology? “Maybe, maybe not,” Reid says wryly. “We might get cut off for getting the wrong answer.”
Next week in Prague, a group of astronomers are planning to tell the
International Astronomical Union--the body that decides, officially,
what is or is not a planet--that there are not nine planets, but 12.
