NASA’s rover Opportunity finds water on Mars…
SCIENTISTS have called NASA’s Opportunity rover gimpy and arthritic, but hailed its new discoveries about early water on Mars made almost 10 years after it was launched toward the Red Planet.
The unmanned solar-powered vehicle has just analysed what may be its oldest rock ever, known as Esperance 6. It contains evidence that potentially life-supporting water once flowed in abundance, leaving clay minerals behind.
“This is powerful evidence that water interacted with this rock and changed its chemistry, changed its mineralogy in a dramatic way,” said principal investigator Steve Squyres of Cornell University.
He described the research as “some of the most important” of the decade-long mission because it showcases a very different chemistry than most of the previous discoveries about water on Mars, which is now quite dry.
Scientists believe that a lot of water once flowed through these rocks through some sort of fracture, leaving an unusually high concentration of clay.
The rover’s rock abrasion tool, alpha particle X-ray spectrometer and microscopic imager provided the details to Earth-based scientists, who can learn about the Red Planet’s history without bringing its rocks to Earth.
Opportunity and its twin rover Spirit launched in 2003 and landed in January 2004 for what was initially meant to be a three-month exploration. Both discovered evidence of wet environments on ancient Mars.
“What Opportunity has mostly discovered evidence for was sulfuric acid,” Squyres told reporters, outlining the major difference detected in the Esperance rock’s formation. “This is water you could drink,” he said.
The oldest rocks, like Esperance, have a neutral pH, signalling that early Martian water was “probably much more favourable in its chemistry, in its pH, in its level of acidity for things like prebiotic chemistry, the kind of chemistry that could lead to the origin of life.”
Squyres said the six-wheeled Opportunity rover “has kind of a gimpy shoulder” and that analysis of Esperance took seven tries over many weeks as the rover endured a dust storm, a lumpy terrain and a period when Mars went behind the Sun and out of contact with Earth.
Now, Opportunity is slowly making its way – about 50m per day) – toward an area 1.5km away known as Solander Point that contains 10 times as many geological layers for study as the area where Esperance was found.
It hopes to arrive by August 1.
Spirit launched on June 10, 2003 and finally stopped working in 2010. Opportunity left Earth on July 7, 2003. Both rovers landed on Mars in January 2004.
“Opportunity is remarkably good health for her age, especially if you measure that in dog years,” said John Callas, project manager for Opportunity at NASA’s Jet Propulsion Laboratory in Pasadena, California.
“The rover’s health is essentially unchanged since we last reported. There has been some arthritis in a few mechanisms for some time but the drive system is performing well.”
In all these years, the rover has travelled 36km on the surface of Mars. But for the rover, that is the car-equivalent of lasting two million miles without an oil change, scientists said.
The main ageing concern is what Callas called occasional “flash memory amnesia,” or a wearing out from over use of one of the flash memory cells. Bigger problems loom with Mars’ hostile environment and harsh temperature changes, he said.
“The rover could have a catastrophic failure at any moment. So each day is a gift,” said Callas.
The Opportunity rover now costs about $14 million per year to operate, NASA scientists said.
Its much bigger cousin, the $2.5 billion nuclear-powered Curiosity rover, arrived on Mars in August 2012 for an anticipated two-year mission and a further hunt for traces that life may once have existed.
In Wind Tunnels and Flight Tests, NASA’s Next Manned Spacecraft Are Taking Shape…
Boeing, SpaceX and the Sierra Nevada Corporation have achieved major milestones in their space programs, testing the vehicles they hope will carry astronauts into orbit and reestablish NASA’s manned space program. NASA is providing a total of more than $1 billion in funding to the three companies to develop a new spacecraft. The agency has said it most likely will select a single design and hopes to begin flying astronauts to the International Space Station by 2017.
The three companies are hip-deep in NASA’s commercial crew integrated capability program, competing for lucrative government contracts to shuttle astronauts to and from the International Space Station and other destinations in low Earth orbit.
Boeing recently tested its CST-100 spacecraft and the integrated Atlas V launch vehicle in NASA’s transonic wind tunnel at Ames Research Center in California. The tests, which Boeing deemed a success, were the first with the spacecraft and launch vehicle integrated, and concluded more than two months’ work at the tunnel. The scale model of the Atlas V and CST-100 were heavily instrumented to gather data on the aerodynamic forces experienced by the rocket and spacecraft during launch.
“The CST-100 and Atlas V, connected with the launch vehicle adapter, performed exactly as expected,” Boeing vice president John Mulholland said in a statement. “[The tests] confirmed our expectations of how they will perform together in flight.”
SpaceX and Sierra also continue making progress. SpaceX recently completed its pad abort test review with NASA, demonstrating where and how astronauts will escape should something go wrong during launch.
More impressively, SpaceX recently performed the first firing of its Falcon 9-R rocket prototype. The new design upgrades the firepower to nine Merlin 1D engines, with eight of them arranged around a central engine instead of a three-by-three square. Company founder Elon Musk says the new rocket,tested in Texas, generates around 1.5 million pounds of vacuum thrust and claims that number will be 60 percent higher with future improvements.
Sierra Nevada stands alone in shunning a capsule in favor of a lifting body design. It borrows from earlier NASA designs and can, like the space shuttle orbiters, return to a runway. The Dream Chaser, which recently arrived at NASA’s Dryden Flight Research Center, soon will begin flight testing, beginning with simple tows down the runway to make sure the landing gear and brakes are working properly. Sierra Nevada plans unmanned drop tests from a helicopter later this summer, providing data for the glide and approach phases of the flight.
The company also announced that initial testing began this week of the rocket motors that will be used on the Dream Chaser. The initial boost of the Dream Chaser will happen while it is perched atop an Atlas V, but once the vehicle separates from the first stage, a pair of hybrid rocket motors will boost the spacecraft into final orbit and rendezvous with the International Space Station. The solid rubber fuel rocket motors are similar to the one used on Virgin Galactic’s SpaceShipTwo.