Near midnight of August 5, the Mars Science Laboratory spacecraft will enter the Martian atmosphere at some 13,200 miles per hour. It has at most seven minutes to lose all that speed or the Curiosity rover it’s carrying will face a very hard landing.
There’s an awful lot riding on this mission, so millions of people around the world will be holding their collective breaths as the moment of entry arrives.
Why all the sudden interest in Mars? Three basic reasons.
AN ANCIENT CRATER
If all goes well, the one-ton rover will land in the ancient and scientifically enticing Gale Crater. Its primary goal: Searching for the building blocks of possible Martian life, and the habitats where it may have once thrived.
NASA has successfully sent six landers or rovers to Mars, but none have been to a site nearly as promising. We already know that Gale Crater was covered in water long ago, that minerals that can be formed only in water are present, and that potentially habitable clays are also there. Add the geology waiting to be read on the exposed sides of the three-mile high mountain at the crater’s center, and you have a planetary scientist’s dream location.
LONG WAY SINCE VIKING
Gerald Ford was president and we were celebrating the nation’s Bicentennial in 1976—the only other time that spacecraft looking for signs of Martian life has landed on the planet.
To the disappointment of many, NASA ultimately concluded that the instruments on the twin Viking landers did not find any signs of life. The take-home message from Viking effectively shut down the Mars program for several decades and took Martian life-detection and astrobiology off the table.
But we know a lot more about Mars now. We know that it was once significantly wetter and warmer, that water ice remains collected under the surface and may even run in warm seasons, that minerals created only in the presence of water are common, that the gas methane (on Earth, overwhelmingly produced through biology) erupts periodically from some Martian locales.
The case for the existence of ancient, or even present, primitive microbial life is increasingly strong, and the ability of NASA instruments to detect the makings of that life has also grown enormously since Viking.
The nation has spent some $2.5 billion for the Curiosity mission—for its three portable chemistry labs, its laser rock zapper, its super high-tech cameras, its ability to roam and even climb part of that nearby mountain (called Mount Sharp).
If it succeeds in finding those Martian building blocks of life, or other promising signs of former extraterrestrial life, Curiosity will be among humankind’s greatest achievements. It will give an enormous boost to the otherwise flagging American Mars program.
But if it crashes at landing or its instruments fail – well, NASA scientists and engineers, as well as the legion of Mars aficionados around the world, don’t want to even think about what that might do to future Mars exploration.
Talk about pressure, talk about drama. The stakes could hardly be higher.
Marc Kaufman is a journalist with The Washington Post and author of National Geographic’s “Mars Landing 2012: Inside NASA’s Curiosity Mission.” He is also the author of “First Contact: Scientific Breakthroughs in the Hunt for Life Beyond Earth,” published by Simon & Schuster.