Posted on 03/26/2020 7:35:10 PM PDT by BenLurkin
NASA's DART (Double Asteroid Redirection Test) mission is scheduled to launch on July 22, 2021. It's a demonstration mission to study the use of kinetic impact to deflect an asteroid. It'll head for the tiny binary asteroid system called Didymos, (or 65803 Didymos.) This double asteroid system poses no threat to Earth.
The larger of the pair, named Didymos A, is about 780 meters (2560 ft.) in diameter, while the smaller one, Didymos B, is only about 160 meters (535 ft.) DART will crash itself into the Didymos B. It's close to the typical size of an asteroid that threatens Earth.
DART has a lot of space to cover to reach Didymos. After launching in July 2021, it will reach its target in September 22nd, when the binary asteroid is within 11 million km (6.8 million miles) of Earth. And to get there, it'll rely on a powerful ion engine called NASA's Evolutionary Xenon ThrusterCommercial (NEXT-C).
The engine comes in two primary components: the thruster and the power processing unit (PPU.) NEXT-C is getting ready for the mission with a series of tests, both performance and environmental. The thruster was put through vibration, thermal vacuum and performance tests before being integrated with its PPU. It was also subjected to simulated spaceflight conditions: the extreme vibration during launch, and the extreme cold of space.
NEXT-C is ... about three times more powerful than the NSTAR ion drives on NASA's DAWN and Deep Space One spacecraft.
NEXT can produce 6.9 kW thrust power and 236 mN thrust. The engine has produced the highest total impulse of any ion engine: 17 MN·s. It also has a specific impulse, which is a measure of how efficiently it uses propellant, of 4,190 seconds, compared to NSTAR's 3,120.
(Excerpt) Read more at phys.org ...
Not until you smack into it with a spaceship it doesn't.
Yeah, trust me and my Viper pool que, you don’t hit the ball with the right amount of English, and you’re gonna redistribute the landscape on that felt. LOL
So, if NASA was to redirect the asteroid and it caused Planet X in an alternate galaxy to be destroyed would there be hell to pay when the Mother ship arrived to extract vengeance?
Will the mission director reluctantly say, “Missed it by THAT much!”
Specific impulse of 4,190 sec is remarkable.
The Space Shuttle main engine (SSME) specific impulse is 452 sec in vacuum.
The Apollo Command and Service Module SPS main engine had specific impulse of 314 seconds, but that was because they used hypergolic fuel with somewhat lower energy density than liquid hydrogen and liquid oxygen used by the SSME. That was because the SPS absolutely had to start.
*ping*
Khan wound up marooned on Didymos B. I smell trouble.
This double asteroid system poses no threat to Earth currently but, after the experiment, all bets are off
"She can ride on my nuke any day!"
"She can ride on my nuke any day!"
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