As NASA's Curiosity rover reaches the first anniversary of its successful landing on Mars, the $2.5 billion mission's team members are looking back at groundbreaking discoveries about the Red Planet's habitability in ancient times — and looking ahead to a marathon trek in the year ahead.
In the 12 months since Curiosity touched down on the night of Aug. 5-6, 2012, the rover has sent back more than 190 gigabits of data, including more than 70,000 images of various sizes. It has fired more than 75,000 laser shots to study the composition of Martian rocks and soil. And it's already achieved its main science goal.
"What we found was surprisingly good, and surprisingly in line with the mission's objective of looking for habitable environments in early Mars history," Ashwin Vasavada, deputy project scientist for the Mars Science Laboratory mission, told NBC News. "The complication is that we underestimated the time it took to do these tasks with the rover by a large fraction — maybe by a factor of two."
That means the six-wheeled, SUV-sized rover will be hustling to get to its prime destination, a 3-mile-high (5-kilometer-high) mountain known as Aeolis Mons or Mount Sharp. Over the past year, Curiosity has traveled about a mile (1.6 kilometers). Over the next year, it's scheduled to go five times that far.
"The default is to drive as far as we can ... any science we do is filled in around the edges," Vasavada said. That being said, the science team is already scanning through orbital imagery, looking for spots along the way that can help flesh out the story of ancient Martian habitability.
The story so far has exceeded expectations. In advance of Curiosity's launch in 2011, the rover team targeted Gale Crater because of Mount Sharp: A close analysis of its layers of rocks could reveal billions of years' worth of geologic history, something that past missions to Mars just couldn't do. But scientists also took note of a fanlike feature that spread out inside the crater. The fan suggested that water once flowed down from higher elevations. If Curiosity came down anywhere close to that formation, the team was prepared to take a detour before sending the rover to Mount Sharp — and that's just what happened.
"Luck favors the prepared," Vasavada said.
What lies ahead
Based on their initial analysis of the area's geological composition, scientists determined that Curiosity was traveling through an ancient streambed. Months later, the rover drilled into rocks in a locale known as Yellowknife Bay and analyzed the gray dust that came from within. Scientists saw the chemical signature of interaction with water that had a neutral pH balance — just the kind of water that could have sustained garden-variety microbes long ago.
How long ago? Probably billions of years ago, before Mars lost much of its atmosphere and surface water. Vasavada said the science team is currently in the process of deciphering the time sequence for habitability.
"It's a question of putting the habitable environment that we found at Yellowknife Bay into the geologic story of Gale Crater — right now we're lacking some of the pieces of the puzzle," he said.
The next year is all about filling in gaps in the puzzle, and getting ready for the next big pieces to fall into place at Mount Sharp. It might take more than a year to fit those pieces together, but Curiosity's original two-year mission has already been extended indefinitely. And thanks to its radioisotope-based power plant, the rover could conceivably keep going for decades longer.
"We're just going to go as long as NASA lets us," Vasavada said.
Based on the good vibrations coming from NASA Headquarters in Washington for the anniversary, that could be a long, long time.
"Successes of our Curiosity -- that dramatic touchdown a year ago and the science findings since then — advance us toward further exploration, including sending humans to an asteroid and Mars," NASA Administrator Charles Bolden said in a congratulatory news release. "Wheel tracks now will lead to bootprints later."
To celebrate the anniversary, the space agency has scheduled an hours-long broadcast on Tuesday, starting with a recorded panel discussion looking back at the landing and the first year of Curiosity's mission (10:45 a.m. to noon ET).
NASA Headquarters will present a live program from noon to 1:30 p.m. ET. NASA officials and crew members aboard the International Space Station will celebrate the rover anniversary and look ahead to the future missions to an asteroid as well as to Mars and its moons. Social-media users can submit questions via Twitter and Google+ by using the hashtag #askNASA.
To tune in the webcast, click on NASA TV or Ustream. And to follow the conversation online about Curiosity’s first year on Mars, watch for the hashtag #1YearOnMars or follow @NASA and @MarsCuriosity on Twitter.
More about Mars:
- Take a billion-pixel tour of Mars
- Curiosity rover is heading for the hills
- NBC News archive on Curiosity's mission
Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding +Alan Boyle to your Google+ circles. To keep up with NBCNews.com's stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.