Rolling up to the crater’s edge, the Opportunity rover Shot in a landscape unlike anything any Earthling had ever seen.
A vast, meteorite-blasted expanse of volcanic stone and iron oxide extended for 15 miles, ringed by rugged mountains under a dusky orange sky. In months ahead, the enterprising robot would uncover signs that warm, liquid water had altered these ancient stones – proof that the conditions for life once existed on Mars.
“That view was among the most spectacular things I’ve ever seen,” recalled Ashley Stroupe, the engineer that was driving the spacecraft the day it came at Endeavour Crater on Mars in August 2011.
And although she had been sitting a hundred million miles off, in Mission Control at the Jet Propulsion Laboratory in Pasadena, California, at that instant Stroupe felt like the astronaut she had grown up always wanting to be. Opportunity had enabled her, and her fellow scientists, along with her fellow humans, to encounter another planet.
Opportunity’s historic mission, that uncovered signs of Mars’ watery past and transformed our comprehension of the Red Earth, has finally come to an end after 15 years, NASA announced Wednesday.
The cause was strategy failure precipitated by power loss during a catastrophic, planetwide dust storm that engulfed the Mars rover last summer.
“But at the exact same time, we’ve got to bear in mind this has been 15 decades of incredible adventure.”
Opportunity’s mission was planned to last just 90 days, but it worked for 5,000 Martian”sols” (that are about 39 minutes longer than an Earth day) and traversed over 28 treacherous miles – 2 documents to NASA.
“It will be a very long time,” Callas predicted,”prior to any other assignment exceeds that length or distance on the surface of another world.”
Before 2000, when NASA announced its ambitious plan for the Mars Exploration Rover (MER) mission, only three spacecraft had ever successfully operated on the Red Earth. Of these, only one – the little Sojourner rover that accompanied the 1997 Pathfinder mission – transferred around on the surface. It never travelled more than 100 meters and lasted less than three months.
The pictures these travellers sent back were cryptic and bleak. Though scientists had theorized about the prospect of finding life on the Red Planet, initial investigations revealed a world with no liquid water, barely any atmosphere and a deadly daily dose of radiation.
Now, roughly two-thirds of missions destined for Mars had failed, often in costly and awkward ways. In 1999 alone, a unit conversion mix-up and a missing line of computer signal doomed an orbiter and 2 landers, costing at NASA a combined $200 million (roughly Rs. 1,400 crores).
The bureau’s chief scientist, Ed Weiler, called the failures”a call” For decades, NASA had chased a”better, faster, cheaper” mining strategy, attempting to utilize a diminishing budget to send a few tiny missions into space. What would this desolate world possibly teach us would be worth the expense?
NASA would require a $800 million risk to find out.
Soon after the crashes, Cornell University planetary scientist Steve Squyres got an unexpected phone call. He had been trying to persuade NASA to send a complex robotic geologist to Mars for more than a decade. Now the agency wanted to know could he have his thought ready to start by 2003?
Ready, set, go!’ And when we had to be on top of the rockets at Florida,” Squyres explained. “People say ,’Oh my goodness, it is a wonder the rover lasted so long on Mars,’ and I want to go,’it is a wonder that they got to the launchpad.'”
The new plan was to place a package of scientific tools developed by Squyres and his colleagues atop two rovers known as Spirit and Opportunity. The task of building these portable robotic geologists proven to be herculean. Dimensions changed, parachute tests failed, launches were delayed by poor weather and battery glitches.
Squyres recalled a sticky summer night in 2003, following the scrubbing of yet another launch, when he took a stroll on the shore near Cape Canaveral to clean his head.
On the East, he watched Mars – just a small red dot – rise over the glittering black Atlantic. It was hard to imagine how the rovers would get there, Squyres said. Mars seemed so forbidding, so alien, so impossibly far off.
“I had been in the control room” at JPL, Squyres recalled. He whined,”Which, interestingly, is a place where we don’t have any control at all.”
The logistics of the MER rover landings were formidable, bordering on absurd. Within half an hour of entering Mars’ thin carbon dioxide atmosphere, the spacecraft had to slow from 12,000 miles to just about 0. Right before impact, a cocoon of air bags scattered round the spacecraft, allowing it to bounce safely on the surface of the Red Planet.
For a moment, the spacecraft’s radio connection was dropped as it shuddered to a standstill. And then a sign appeared on the computer screen in front of EDL supervisor Rob Manning. He flung out his arm and leaned back in his seat.
Planetary scientist Abigail Fraeman, then 16, had been invited to JPL within a Planetary Society application for high school pupils. She can still muster every detail of that night. The tones that rang out as every system was discovered healthy. The images that Opportunity sent from its landing site of a smooth dark plain so vibrant and sharp she felt she could reach out and touch it. The explosion of elation that swept through the science team as investigators realized what they’d landed on: layers of exposed bedrock that would reveal clues about Mars’ geologic history stretching back billions of years.
“I realized that I wanted to be among those people who may jump up and down,” Fraeman said. “I needed to become somebody who could comprehend the importance of what those pictures were telling us.”
Fraeman wound up going to college for physics and geology, then making her PhD in planetary geoscience. Since 2016, she has served as the deputy project scientist for the Opportunity mission.
Opportunity’s first great accomplishment came within two weeks of its arrival on the Red Planet. The layered outcrop on which the rover had landed – the one that made the scientists enclosing Fraeman jump for joy – contained evidence that water once flowed through the stones crystals, sulfur compounds, little spherical items that scientists dared to blueberries, along with rock patterns that seemed like sediments laid down with a flowing current.
This evidence constituted a”giant leap” toward discovering if Mars ever hosted life, Weiler told The Post.
That discovery was bolstered by dozens more like it. Opportunity went to locate hematite, an iron mineral generally associated with water, and a strand of gypsum, which likely shaped from mineral-rich water moving through stone.
“It really changed the way scientists perceive Mars,” said Squyres, that has been principal investigator for the instruments aboard Spirit and Opportunity since the beginning of their assignment. “It’s a cold and desolate world today, but in the remote past, in the time that the rocks explored by Spirit and Opportunity were formed, it was a very different universe. It was a world that was more Earthlike, a time when life has been emerging on Earth.”
“Therefore it makes you seriously think about,” he continued,”when it happened on Earth, which it did, would it have happened beneath the warmer, wetter conditions that once existed on Mars?”
Opportunity, he said,”could not answer that question. But we helped framework it.”
Those discoveries helped build the case for following missions to Mars, for example, Curiosity rover, which landed in 2012 and is still exploring the Red Planet, and a 2020 mission which will collect rock samples for eventual return to Earth.
Opportunity’s scientific achievements were only possible because it had been such an engineering success, said NASA’s acting manager of planetary science Lori Glaze. The rover was adaptable, tenacious and diligent, and its drivers never failed to receive it to its aims.
“Being able to really roll up to an outcrop and examine it, to appear close with your hand lens, do the chemistry dimensions… it allows you to really feel as though you’re there,” she explained. “That absolutely changed the way we go about performing planetary exploration”
The MER mission’s cultural legacy is just as wide-reaching. Middle school science courses monitored the rovers’ progress across the Martian landscape. A Twitter account shared selfies and snarky remarks in the spacecraft’s voice.
When Opportunity went silent last summer, more than 10,000 fans sent the spacecraft electronic”postcards” wanting it well.
“Wake up little friend!” One read.
Even the scientists that operated the spacecraft couldn’t help but anthropomorphize them. Stroupe, the JPL engineer, jokes Spirit and Opportunity had”the dynamic of being equal siblings.” Spirit, which landed on Mars first, faced much tougher terrain and suffered several breakdowns, culminating in the rover’s eventual loss of contact in 2010.
Since the”younger child,” Stroupe said,”what kind of came easy to Oppy.” The engineer laughed. “I mean, she found signs of water until we even drove off the lander!”
The charmed rover barely escaped becoming trapped in a sand dune at 2005, survived a worldwide dust storm in 2007, and undertook the longest-ever traverse performed by means of a rover – the three-year journey from its landing site at Victoria Crater to Endeavour Crater, 13 kilometers away.
She calls for Spirit and Opportunity”the initial Martians” – the first things to live and work more on another planet than they ever did on Earth.
And as a procedures and systems engineer for NASA’s Mars missions, accountable for driving robots round unforgiving alien terrain,”I really do feel somewhat like I’ve naturalized double citizenship,” Stroupe added.
A sticker in her office acknowledges,”My other vehicle is on Mars.” She uses an app on her phone to track the 24-hour, 39-minute Martian day. When she closes her eyes to sleep, rusty landscapes and dust-filled skies are the background for her fantasies.
In May 2018, scientists at JPL received a worrying weather record from NASA’s Martian satellites: A large dust storm was brewing just a few hundred miles from Opportunity, blocking out the solar-powered rover’s perspective of sunlight.
The spacecraft had survived such storms earlier. However, at more than 14 years old, it wasn’t any longer as hardy as it had once been. A fault in one of Opportunity’s memory banks resulted in reduction of long-term memory. Issues with the rover’s wheels and robotic arm seemed like spacecraft arthritis. In case Opportunity experienced another protracted power loss, it may not recover so readily.
By June, the dust storm had grown into a planet-encircling event, among the most ferocious NASA had ever seen. It seemed likely that Opportunity could undergo a low-power fault, putting itself to sleep before the skies cleared. Efforts to make contact with the spacecraft went unanswered.
When the storm finally began to subside, in September, NASA adopted a”sweep and beep” plan for waking the rover, sending commands multiple times per day. Except for a couple of false alerts from other spacecraft – NASA’s Mars Reconnaissance Orbiter transmits on an identical frequency – scientists discovered nothing back.
If the storm had deposited dust Opportunity’s solar panels, then the forthcoming windy season – which runs from November to January – might help sweep them blank.
“The hardest part was the not knowing,” Stroupe said.
After sending more than 835 recovery commands to the spacecraft, including a last-ditch app that would fully reboot Opportunity’s clock, expect started to dwindle. Every day that passed, Callas stated, it became less likely that NASA would ever get a response to its hectic calls.
The very last sign was sent from JPL on Tuesday night.
“We have exhausted all of the excellent ideas [for waking the rover]… and we announce the assignment as being whole.”
A meeting with all the mission’s scientists and engineers this week felt almost like a funeral, Zurbuchen said. Researchers cried not just for the passing of their rover, but for the disintegration of a 15-year-old team.
However, Squyres was resolute as the mission drew to a closefriend.
“I always knew it was about to finish,” he explained. “And boy, if that is the ending… getting killed by one of the most ferocious storms we have ever seen. Well, you can walk away from this with your head held high.”
NASA’s next rover mission, which will seek outward signs of early life, will start in 2020.
“It’s going to be there,” Zurbuchen said,”just like a monument, or even a shipwreck.”
It is a mark of where humankind has been.