Spirit on the Lake

Mars Opportunity Cloud Cover
NASA’s Mars Exploration Rover Spirit looked back with its navigation camera during the rover’s 332nd martian day, or sol (Dec. 8, 2004), and captured this image. Spirit had driven about 110 meters (120 yards) during the preceding six sols.Click image for larger view.
Image Credit: NASA/JPL

Six years ago, then NASA Associate Administrator Wesley Huntress, Jr., stated , "Wherever liquid water and chemical energy are found, there is life. There is no exception." Few opportune years like 2004 have presented astrobiology with as many remarkable vistas and fresh perspectives on this fundamental triad of water, chemical energy and life.

Consider this year’s accomplishments of those dedicated to searching for life in the universe.

Landing on Mars not once, but twice. Then finding evidence for water on opposite sides of the red planet. Picking up what appears to be methane signals in the martian atmosphere, one of the residues that might prove one day to be the product of underground biology. Scientists began to discuss seriously what colonization strategies make sense.

Setting off to explore the even richer atmosphere of the Earth-like moon, Titan. Spiraling into orbital capture around Saturn and photographing its majestic rings.

Flying through the tail of a comet and heading home after collecting the first extraterrestrial samples from such dusty iceballs. Launching the Deep Impact probe to smash into a comet and watch how the dust and ice get kicked up.

Filling the astronomy catalogs with well over a hundred new planets, including what may prove to be the first visible exoplanet. Finding some nearby candidates that might occupy temperate locations or safely orbit Sun-like stars.

Witnessing the once-per-century passage of our neighboring Venus across the face of the Sun. The MESSENGER probe took off on its decade long tour of the inner solar system to orbit Mercury.

Mars Opportunity Cloud Cover
Spirit rover tracks near Columbia Hills. Click image for larger view.
Image Credit: NASA/JPL

Discovering the largest planetoids beyond Pluto among those outer nurseries where only comets visit.

The editors of Astrobiology Magazine revisit the highlights of the year and where possible point to one of the strongest lineups ever for beginning a new turn of the calendar. Between the marathon still being run by the twin Mars rovers and the expected descent to Saturn’s moon, Titan, next year promises no letdowns.

Number four on the countdown of 2004 highlights was the Mars Spirit rover and its exploration of Gusev Crater.

Concretions in a similar setting at Gusev as also observed at Meridiani.
Image Credit: NASA


One of the primary goals of the rover missions was to learn once and for all if liquid water ever existed on the red planet. Of the twin rovers, the Opportunity rover has found clues to briny lakes or even a sea on the opposite side of Mars compared to where the Spirit rover currently sits perched near a summit. The Spirit rover was the first successful lander to touchdown since 1997, when the Pathfinder mission began exploring Mars on wheels. Spirit holds the distance record for miles covered since landing in Gusev Crater and beginning its tour of the Columbia Hills.

"With Spirit, the immediate plan is to continue to work our way up through the Columbia Hills," said principal investigator, Steve Squyres of Cornell. "We’re very much in discovery mode in that mission. With the Opportunity rover in Eagle crater, in our first six to eight weeks, we were in discovery mode, where every day there was some new revelation about the rocks. And that helped us to form a set of hypotheses that we could use at Endurance crater to systematically test."

"Where we are with Spirit right now is sort of like where we were with Opportunity at Eagle crater," continued Squyres. "We had all that basalt out on the plains, and Spirit did its thing there, and it took us about 160 sols just to get to the Columbia Hills. But since arriving there each new rock, each new outcrop, is some new piece of the puzzle."

What Next?

– Mars Reconnaissance Orbiter (MRO) launch, Mars Orbiter to collect high-resolution, 1-meter, images in stereo-view of Mars
– European Venus Express, Venus Orbiter for two-year nominal mapping life [486 days, two Venus year]

New Horizons, Pluto and moon Charon flyby, mapping to outer solar system cometary fields and Kuiper Belt
Dawn, Asteroid Ceres and Vesta rendezvous and orbiter, including investigations of asteroid water and influence on meteors
Kepler, Extrasolar Terrestrial Planet Detection Mission, designed to look for transiting or earth-size planets that eclipse their parent stars [survey 100,000 stars]
Europa Orbiter, planned Orbiter of Jupiters ice-covered moon, Europa, uses a radar sounder to bounce radio waves through the ice
– Japanese SELENE Lunar Orbiter and Lander, to probe the origin and evolution of the moon

– Japanese Planet-C Venus Orbiter, to study the Venusian atmosphere, lightning, and volcanoes.
– Mars Scout mission, final selections August 2003 from four Scouts: SCIM, ARES, MARVEL and Phoenix
– French Mars Remote Sensing Orbiter and four small Netlanders, linked by Italian communications orbiter

BepiColumbo, European Mercury Orbiters and Lander, including Japanese collaborators, lander to operate for one week on surface
Mars 2009, proposed long-range rover to demonstrate hazard avoidance and accurate landing dynamics

Related Web Pages

2003: Year in Review
Solar System Exploration Survey
Mars Opportunity Rover
Mars Spirit Rover
Mars Express
Mars Methane
New Planets
Saturn Cassini
Venus Occultation
Planet Ten: Beyond Pluto?