Drilling For Extreme Life
For the past 20 million years, Lake Vostok has been sealed beneath the Antarctic ice sheet. This winter, after nearly 22 years of work, Russian researchers will use mechanical and thermal drills to punch through the final 100 feet before liquid water. Microbes found in Vostok could inform the search for life on the Jovian ice moon Europa, for which a mission could launch in the next decade, and other moons in our solar system thought to contain bodies of liquid water, such as Enceladus and Ganymede.
Drilling For Extreme Life: How It Works
THE SITE
Vostok Station once recorded the lowest temperature on Earth: –128ºF. Fortunately for researchers, average temperatures in the austral summer hover around –33º.The Russian team will commence drilling in December. Once scientists reach liquid water, they will allow water to rise up the borehole and freeze over the winter. They will return to Vostok Station in December 2012 to test the core for life.
THE DRILL
A thermal drill tethered to a power cable from the surface will penetrate the final 30 feet of ice. When the drill approaches the water surface, pressure and water sensors will trigger an expandable borehole packer to seal off the channel, preventing drilling fluid from contaminating the lake and allowing scientists to control how quickly the water will rise.
THE LAKE
Lake Vostok, one of the world’s largest lakes by volume, contains more than 1,000 cubic miles of water. At its farthest depths, some 14,000 feet below the surface, pressure reaches up to 438 atmospheres. If drilled improperly, the pressurized water could race up the borehole, causing an explosion powerful enough to destroy Vostok Station.
Bringing Mars Home, Part One
To determine whether life lives or has lived on Mars, scientists will most likely need to bring a sample of the planet back to Earth. The threestage NASA-ESA Mars Sample Return mission, scheduled to run from 2018 to 2027, will involve rovers, a launcher, and an orbiter equipped with an Earth Entry Vehicle (EEV) that will carry the rocks to Earth for testing.
PHASE ONE, 2019-2021: COLLECT AND CACHE
Following launch in 2018, a rover will arrive on Mars in January 2019 and will spend nearly two years collecting rocks with a rotary coring drill. After placing as many as 40 cores in a three-inch-wide cylindrical cache, the mobile ’bot will return to its landing site and place the container on the ground.
Bringing Mars Home, Part Two
PHASE TWO, 2025-2026: FETCH AND LAUNCH
A lander carrying the fetch rover and Mars Ascent Vehicle (MAV) will touch down on Mars in September 2025. Over the next three months, the rover will retrieve the cache—up to a nine-mile round-trip journey—and package the rocks in an 11-pound Orbiting Sample (OS) sphere stored inside the MAV. By the following May, the MAV rocket will launch and release the OS into orbit.
Bringing Mars Home, Part Three
PHASE THREE, 2026-2027: RENDEZVOUS AND RETURN
An orbiter will arrive at Mars in the summer of 2023. The craft will use optical and radio-frequency tracking systems to monitor the OS launch and will rendezvous with the samples in around May 2026. The orbiter will capture the OS in a basket and transfer it to the onboard eeV—a three-foot-wide, impact-resistant, heat-shielded craft—before setting out for Earth. On descent to Earth in late 2027, the EEV will decouple from the orbiter and crash-land on the planet. The quarantined samples would then be safely recovered.
Spotting Distant Life
To view life on other worlds, scientists will need to use a space-based telescope to scan for biosignatures in an exoplanet’s atmosphere while blocking out starlight that could skew results. The New Worlds Observer, a design developed at the University of Colorado, pairs an ultraviolet-optical-infrared telescope with an external starshade.
THE STARSHADE
The 160-foot-wide starshade moves independently to position itself between the telescope and the star. Its 16 “petals” diffract light away from the center of the shadow it casts onto the observatory.
THE TELESCOPE
The observatory’s 13-foot aperture will collect enough ultraviolet and infrared light reflecting off the planet to distinguish it from interplanetary dust. Future telescope designs will also probably incorporate an internal coronagraph, a device on the instrument that will blot out starlight that slips past the shade.
Searching For New Earths
In 1995 a Swiss team scanning the Milky Way discovered 51 Pegasi b, the first known exoplanet orbiting a sunlike star. Since then, scientists using ground-based and space telescopes have found more than 500 exoplanets in the galaxy. Currently only one, Gliese 581 d is considered a potential Earth analogue—it may even have oceans—but the number will grow. Kepler, a photometric telescope that points toward the constellations Cygnus and Lyra, could find as many as 3,000 new worlds by the end of the decade.
Do Good, Find Aliens
In April, after the National Science Foundation and the state of California cut funding for radio astronomy, the Allen Telescope Array (ATA) at Hat Creek Radio Observatory, the SETI Institute’s primary listening post, went dark for the first time in nearly four years. The ATA scans deep space for alien radio signals, which some scientists say could be our best chance of finding intelligent life.
To replace the estimated $5 million it will cost to get the ATA back online full time for two years, SETI introduced a new program called SETIStars in June. For $15, donors can sponsor three-minute blocks of telescope data. In March, SETI launched the beta version of another program, a citizen-science application called setiQuest Explorer. Amateur alien hunters will be able to analyze radio-telescope data for signs of contact on their computers, tablet or mobile phone. The institute’s public outreach is paying off. By August, SETIStars had generated more than $200,000, enough to turn the ATA back on, at least for a little while.
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