Man's 1st attempt at planetary defense

RadishRose

RadishRose

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Connecticut, USA
Nasa's DART hits an asteroid some 7 million miles away. You don't see an explosion. You are the rocket and getting up close to the asteroid, of course that would be all you could see before the camera goes out. A bit anti-climactic, but still interesting.

Someday if we last that long, we may be able to repel a large asteroid from hitting Earth. The dinosaurs would have liked to have a this defense I guess.

They are now investigating to determine if the rock was knocked off course at all.

 

Here's a picture of the Dodge Dart Spacecraft......:unsure:
iu

Dodge Dart GT Convertible Daroo I Concept Car (1967)
 

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I haven't read any science on how they propose to do this kind of thing eventually, however minus explosives, the straight physics is a matter of known math of mass and momentum vectors. Would expect in the future we could place a large mass in a moon orbit and when necessary, power it towards possible smaller collision bodies. The mass could be mined from the moon and then transported into space with less energy than rocketing up from earth's heavy gravity. Alternatively, could tow an asteroid into such an orbit. In any case there is a limit to how large a body we might be able to move much less deflect. The further from Earth before a potential collision, the less energy/mass would be needed for deflection. However the speed at which many such bodies move relative to the Earth makes moving a mass near them a difficult issue.

A more practical idea may be to place a more mobile extra large rocket up in orbit and use that as a collision mass with speed. Maybe scientist had already thought through what I just mumbled through and that is why they just tried to collide with a rocket at high speed as a first step while expecting a deflection would be minuscule. In other words, any really heavy mass like rock would be difficult and slow to accelerate and hard to aim as well as do so earlier, farther from Earth where it would have more effect.
 
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David777 said:
I haven't read any science on how they propose to do this kind of thing eventually, however minus explosives, the straight physics is a matter of known math of mass and momentum vectors. Would expect in the future we could place a large mass in a moon orbit and when necessary, power it towards possible smaller collision bodies. The mass could be mined from the moon and then transported into space with less energy than rocketing up from earth's heavy gravity. Alternatively, could tow an asteroid into such an orbit. In any case there is a limit to how large a body we might be able to move much less deflect. The further from Earth before a potential collision, the less energy/mass would be needed for deflection. However the speed at which many such bodies move relative to the Earth makes moving a mass near them a difficult issue.

A more practical idea may be to place a more mobile extra large rocket up in orbit and use that as a collision mass with speed. Maybe scientist had already thought through what I just mumbled through and that is why they just tried to collide with a rocket at high speed as a first step while expecting a deflection would be minuscule. In other words, any really heavy mass like rock would be difficult and slow to accelerate and hard to aim.
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I'm not gonna pretend I understand your comments here....but in a way I sort of do. A little, tiny bit.

It will be interesting to follow up on what they learned. It seems impossible to me to be able to move such a huge thing.
 
While it's highly unlikely, in my opinion, that the asteroid's trajectory will be altered by the DART spacecraft slamming into it, Elon Musk no doubt made a healthy profit off the contract, and isn't that what really matters? :ROFLMAO:

Just kidding. SpaceX is a reliable aerospace contractor, unlike some of the other ones out there.

Perhaps blasting the asteroid to bits with nuclear weapons might save us from total anihilation.
 
NASA struggles to get a Moon shot off the pad. Meanwhile is successful in crashing a space craft into a rock. Were I an astronaut training for a manned Moon launch, that would not instill confidence in my chances of survival. Perception is everything.
 
The Bennu asteroid is a half of a kilometer in diameter.

Nuclear impulse could deflect massive asteroid

https://www.llnl.gov/news/nuclear-impulse-could-deflect-massive-asteroid

Unlike popular portrayals of a nuclear deflection mission — like the movie “Armageddon” — the nuclear deflection approach would consist of detonating a nuclear explosive some distance from the asteroid. This would flood one side of the asteroid with X-rays, vaporizing a layer of the surface, which would create rocket-like propulsion as vaporized material is ejected from the asteroid.

“The nuclear option would be the key to deflecting large asteroids,” said Dave Dearborn, LLNL physicist and lead author on the paper. “It also offers flexibility that impactors don’t. For instance, the amount of energy deposited into an asteroid with a nuclear device can be tuned by adjusting how far it is from the asteroid when detonated.”

Researchers estimate that it would take a minimum of 7.4 years before an impulse could be delivered to Bennu. This includes the time it would take to build the spacecraft, plan the mission and travel to the object. Assuming the impulse was successfully delivered, changing its velocity slightly, it would take many years for the small change in speed to accumulate into a sufficient change in trajectory.

Bennu’s highly constrained orbit would lend multiple decades of lead time, if it were to end up on an Earth-bound orbit. But much more uncertainty exists for other objects that do not regularly pass close enough to Earth for radar observations. There are more than 20,000 near-Earth objects (NEOs) found by NASA so far, and scientists estimate that this is just a fraction of the total NEO population. A U.S. Congress-defined goal to discover and track the orbits for 90 percent of NEOs greater than 140 meters in diameter is likely years from completion. An update reported by astronomer Alan Harris at a recent Planetary Defense Conference puts the estimate at approximately 37 percent.

“Time would be our No. 1 enemy,” Bruck Syal said. “That’s why it’s critical that we advance our ability to detect threats through future space-based telescopes like NEOCam, which would be dedicated to hunting down NEOs. We also want to shorten the timeline for making a mitigation decision and launching a deflection mission. The chances of a Bennu-class collision appear slim now, but they aren’t zero and the consequences could be devastating if we aren’t able to act in time. In the end, our ability to protect people and critical infrastructure on Earth could come down to how ready we are to respond quickly.”
 
David777 said:
The Bennu asteroid is a half of a kilometer in diameter.

Nuclear impulse could deflect massive asteroid

https://www.llnl.gov/news/nuclear-impulse-could-deflect-massive-asteroid

Unlike popular portrayals of a nuclear deflection mission — like the movie “Armageddon” — the nuclear deflection approach would consist of detonating a nuclear explosive some distance from the asteroid. This would flood one side of the asteroid with X-rays, vaporizing a layer of the surface, which would create rocket-like propulsion as vaporized material is ejected from the asteroid.

“The nuclear option would be the key to deflecting large asteroids,” said Dave Dearborn, LLNL physicist and lead author on the paper. “It also offers flexibility that impactors don’t. For instance, the amount of energy deposited into an asteroid with a nuclear device can be tuned by adjusting how far it is from the asteroid when detonated.”

Researchers estimate that it would take a minimum of 7.4 years before an impulse could be delivered to Bennu. This includes the time it would take to build the spacecraft, plan the mission and travel to the object. Assuming the impulse was successfully delivered, changing its velocity slightly, it would take many years for the small change in speed to accumulate into a sufficient change in trajectory.

Bennu’s highly constrained orbit would lend multiple decades of lead time, if it were to end up on an Earth-bound orbit. But much more uncertainty exists for other objects that do not regularly pass close enough to Earth for radar observations. There are more than 20,000 near-Earth objects (NEOs) found by NASA so far, and scientists estimate that this is just a fraction of the total NEO population. A U.S. Congress-defined goal to discover and track the orbits for 90 percent of NEOs greater than 140 meters in diameter is likely years from completion. An update reported by astronomer Alan Harris at a recent Planetary Defense Conference puts the estimate at approximately 37 percent.

“Time would be our No. 1 enemy,” Bruck Syal said. “That’s why it’s critical that we advance our ability to detect threats through future space-based telescopes like NEOCam, which would be dedicated to hunting down NEOs. We also want to shorten the timeline for making a mitigation decision and launching a deflection mission. The chances of a Bennu-class collision appear slim now, but they aren’t zero and the consequences could be devastating if we aren’t able to act in time. In the end, our ability to protect people and critical infrastructure on Earth could come down to how ready we are to respond quickly.”
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I wonder if a smaller asteroid could be deflected into the path of a larger asteroid to change its path. That might be a bit tricky.

Blasting an asteroid to bits with nuclear weapons is probably the only feasible option at this point. It would still be highly destructive when the smaller bits hit earth, but it probably wouldn't be the end of civilization.
 


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