Published : Tuesday, May 16, 2017 | 5:21 AM
Scientists working at Pasadena’s Jet Propulsion Laboratory were featured in last Sunday’s episode of “60 Minutes” on CBS, as they talked about how the Mars rover Curiosity was providing clues about how life could have existed on that planet first, then travelled to Earth at some previous time in history, becoming the basis for life here.
It was Rob Manning, Chief Engineer at JPL, who advanced that possibility, as he spoke with 60 Minutes correspondent Bill Whitaker.
“Could have been that Mars was habitable before Earth was,” Manning said in the episode. “And life got its foothold on Mars and took its journey to Earth and we’re all Martians.”
Whitaker visited JPL and reported from offices and laboratories where scientists and engineers were analyzing data collected by the Mars rover and working on a Curiosity “twin” – a replica of the rover – to repair, by remote control, some glitches on the rover as it made its way across barren fields on the red planet.
“From Mars, Curiosity can barely see Earth more than 30-million miles away,” Whitaker says at the beginning of the segment on Curiosity. “But Curiosity is seeing Mars as never before — leaving its mark — its tracks — and sending back postcards of sand dunes — 20-feet tall, extending for miles; ancient stone lakebeds that have been dry for billions of years; and time-lapse pictures of a Martian sunset. Like any vain photographer, Curiosity poses for ‘selfies’ along the way as she works to solve Mars’ most challenging mysteries.”
Whitaker also spoke with Katie Stack Morgan, a JPL research scientist with interests in Martian sedimentology, stratigraphy, and orbital geologic mapping. As a geologist, Morgan helps decide what pictures Curiosity should take and where it should go.
“There’s a pebble right here and it’s actually quite round,” Morgan says as she showed Whitaker images taken by Curiosity of the Martian surface. “And if you think about pebbles that you find in a stream on Earth, they tend to be very round as well, because as they move in the stream pebbles are hitting other pebbles. And they round off all the little corners. That’s how we know this deposit was formed in rushing water. This is the first evidence we have from the surface that water flowed across the surface of Mars.”
Curiosity can zap rocks with a laser beam up to 23 feet away and analyze what they’re made of. It is also the first rover that can drill for samples of Martian soil and then analyze them in its built-in lab.
One of the earlier samples helped scientists at JPL conclude water used to flow on the surface of the planet – Curiosity’s most significant finding so far.
Mars is also telling JPL scientists how different it was on Earth when the two planets were evolving. On Mars, the rocks that Curiosity discovers on the surface are very, very old, they said, unlike on Earth where the surface is constantly changing, and what could have been on the surface centuries ago now underground.
“Most of Earth is constantly recycling, as the plates on the surface move around,” the geologist Morgan says. “But here on Mars we don’t really have evidence for plate tectonics. This is the Mars rock record, of Mars history preserved at the surface. And that’s a really unique opportunity to explore a time in the solar system that may not be preserved on the surface of Earth.”
One of the challenges that NASA had as the agency planned to land Curiosity on Mars was the rover’s size and weight. It couldn’t bounce onto Mars, cushioned by giant airbags, the way smaller rovers had. So what lead engineer Adam Steltzner and his team did was come up with a bizarre plan to pack Curiosity into a flying saucer, fire rockets to slow its descent and then use long cables to lower it onto Mars.
“The team recognized that if we failed we would find no comfort or solace from the general public,” Steltzner tells Whitaker in the episode. “Because the man on the street says, ‘That looks crazy. I could have told you it was crazy.’ And so I developed this little statement I would make before I would even start. It goes like this: ‘Great works and great folly may be indistinguishable at the outset.’”
Then he goes on to relate how the JPL team were just sitting in the control room, biting their fingernails, as they waited for word if the rover ever did succeed on landing.
When it did, the control room, Steltzner said, erupted in glee.
“The team celebrated. And then sometime in the wee hours of the morning I went home, crawled into bed with my wife and wept because I was spent. I was overwhelmed,” Steltzner said.
Morga goes on to explain how Curiosity gathered images and sent them back to Earth for analysis, along with the data that came out rock and soil the rover digged up and analyzed by itself.
At one point, Curiosity’s communications systems seemed to be breaking up, and so Manning and his engineers had to work on the “twin” rover that’s at JPL to find a solution.
“We had had…The rover had some sort of memory problem,” Manning relates. “The pilot (one of two identical computers on the rover; the other is called the copilot) is supposed to have enough self-diagnosis and be smart enough to say, ‘I’m not doing very well. I’m not feeling well. I’m gonna let the copilot take over.’”
Eventually, by working on the “twin,” Manning and his team are able to put the backup pilot in charge, and then were able to repair the pilot and put it back in control of Cusiority.
Near the close of the episode, Whitaker asked why Mars is almost a dead planet, and the discussion turned to if ever Earth could go the same path if Mars were once a planet of life with a habitable atmosphere.
“It cooled, it lost its magnetic field, the solar wind blew away its atmosphere. And so it dried out. It became a prune of its former self,” lead engineer Steltzner says. “We are still a plum; it’s a prune. But it does teach us of how delicate the balance of our environment is. And so it should heighten our appreciation of what a beautiful, warm, wet hug living here on Earth really is.”
Curiosity is the largest and most capable rover ever sent to Mars. It launched November 26, 2011 and landed on Mars on August 5, 2012. The mission set out to answer the question: Did Mars ever have the right environmental conditions to support small life forms called microbes?
Early in its mission, Curiosity’s scientific tools found chemical and mineral evidence of past habitable environments on Mars. It continues to explore the rock record from a time when Mars could have been home to microbial life.
For more information about Curiosity, visit www.mars.nasa.gov/msl/mission/overview.