NASA's only mission in the asteroid belt is dying after 11 years in space – but that could trigger the future discovery of extraterrestrial life, Business Insider

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An illustration of NASA's Dawn spacecraft flying towards Ceres using its ionic thrusters.

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NASA / JPL-Caltech

• NASA launched an ion – propelled probe called Dawn to the asteroid belt in 2007.
• In 2015, Dawn reached Ceres –a dwarf planet the size of Texas that could hide a salty ocean and maybe a foreign life.
• The spacecraft is almost empty and its mission can end between mid-September and mid-October.
• Researchers expect Dawn to remain in orbit for 20 to 50 years, but after that, it may fail Ceres.
• On Friday, NASA hosted a live discussion of Dawn's discoveries and the end of the month.

NASA's only robot exploring the asteroid belt is about to die, the space agency said in a live event on Friday.

However, a last-minute maneuver made it possible to create surface maps of a dwarf planet, information that could be used to send a sample return mission to the far-away world.

The Dawn spacecraft was launched in 2007 and became NASA's first mission to use ultra-efficient ionic thrusters on a multi-year journey into the deep space. The robot ended up in the asteroid belt, the mysterious and expansive area between Mars and Jupiter, where he studied the two largest objects in the region: Ceres and Vesta.

Dawn reached Vesta in July 2011. Vesta is the second largest object in the asteroid belt. the researchers think it is a "time capsule" for planet formation because it has failed to develop after the birth of the solar system.

After a year of exploration at Vesta, Dawn propelled herself to a Texas-sized dwarf planet called Ceres, where she arrived in March 2015. Since then, Dawn has made a number of major discoveries on the ice of a width of 592 miles. the ball, including an ice volcano, shiny salt deposits, and other elements that suggest that a giant ocean could hide under the crater crust of the world – perhaps one that could harbor exotic microbes.

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A false-color view of the dwarf planet Ceres.

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NASA / JPL-Caltech / UCLA / MPS / DLR / IDA

NASA has since used most of Dawn's remaining fuel to slip into an orbit that zooms within 22 miles of the surface of Ceres about once a day.

These nearby overflights are about 10 times closer than the orbits of the International Space Station above the Earth and have resulted in the clearest and sharpest images of the dwarf planet.

"This orbit was like putting on your glasses if you do not see very well. Suddenly, all these details are explained, "Carol Raymond, Dawn's senior research scientist and NASA's Jet Propulsion Laboratory researcher, told reporters Friday. "This will give us an idea of ​​what's going on with the plumbing system below the surface."

However, these images and other unprecedented data have a cost: a death for Dawn before the end of the year.

Why Dawn is now doomed

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A mosaic image of Cerealia Facula: a site with a collection of salt deposits in the crater of Occator, the largest site impact on Ceres.

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NASA / JPL-Caltech / UCLA / MPS / DLR / IDA / PSI

The use of Dawn's fuel to reach such a close orbit essentially blocked the spaceship around Ceres.

"The current orbit should be stable for 50 years," said Mark Sykes, director of the Planetary Science Institute and scientific mission Dawn, in an email. "There is no desire to change the orbit – and no juice."

Dawn uses her "juice" to stay powered and talk to NASA. So using the last thruster will silence the probe forever.

"He will struggle for a short time, but he will be helpless," wrote Marc Rayman, chief of mission and chief engineer of Dawn, August 22. "Unable to point its radio antenna solar panels back to Earth, the seasoned explorer will shut up and no longer explore.His expedition will be completed.

This expedition was to last nine years, but it's been almost 11 years. The team, although sad about the disappearance of the probe, has its blessings, especially because Dawn continues to take high-resolution images of the surface every 27 hours.

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NASA's Dawn spacecraft photographed landslides on the edge of the Occator crater on Ceres, a dwarf planet in the asteroid belt.

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NASA / JPL-Caltech / UCLA / MPS / DLR / IDA

Rayman said Friday that Dawn could shut up in about a month.

"We can not determine this with exquisite precision," he told Business Insider during the press event, adding that it is more likely that the thruster (and that "it" is more likely he stops talking to the Earth) October. "

Once the probe runs out of fuel, it should not lower and sink into Ceres for at least 20 years. In fact, Rayman added that the team has calculated the numbers and that their analysis shows that Dawn has more than a 99% chance of staying in its current orbit for half a century, and probably more than that.

NASA wants to bring back a sample of Ceres on Earth

Rayman says that the minimum of 20 years without collision was an essential requirement of the Dawn mission.

This is because NASA's global protection office – which is trying to prevent the contamination of other worlds by microbes of the Earth – thinks that this should give the agency time to perform another mission for explore the surface of Ceres.

Such a hypothetical mission could look for signs of life without worrying about Dawn's debris – and contamination by Earth microbes stuck to the robot.

"Ceres represents a place in the solar system that interests us for future astrobiological exploration," Rayman said. "If NASA chooses to mount a follow-up mission to conduct a subsequent astrobiological exploration, it will be long enough not to be compromised by Dawn."

Jim Green, chief scientist of NASA, said the agency had assembled working groups to develop a plan to send a robot to the surface of Ceres, possibly near a vent , from the dwarf planet to Earth.

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What planetary scientists think it sounds like Ceres, a dwarf planet in the asteroid belt. The crust is probably made of ice and, below, may be a layer of brackish mud. Its core can be water or metal.

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NASA / JPL-Caltech / UCLA / MPS / DLR / IDA

"We will be asking ourselves over the next decade if any of these missions will actually return to Ceres," Green said on Friday.

The stakes are high because researchers are discovering more and more water and organic compounds elsewhere in the solar system – ingredients that can sustain rudimentary forms of extraterrestrial life.

"We know there is an active geological cycle that brings soil materials to the surface," said Carol Raymond. "It gives us the opportunity to taste the internal material of Ceres."

As Dawn continues to accumulate high resolution images of the surface, the argument in favor of collecting a sample of Ceres could grow.

"The holy grail of any global scientific mission is a return of sample, but it's also very difficult," said Raymond. "With an object like Ceres, you really want to know where to take samples."

This story has been updated with new information. It was released at 1:27 pm EDT on September 7, 2018.