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Drakkith
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Bob I don't see how that relates to the nuke vs high speed kinetic impact question. Perhaps I misunderstood one of your posts?
Simply. Bob states that kinetic hit would be ineffective and nuke blast yes - effective.Drakkith said:Bob I don't see how that relates to the nuke vs high speed kinetic impact question. Perhaps I misunderstood one of your posts?
DrakkithDrakkith said:Bob I don't see how that relates to the nuke vs high speed kinetic impact question. Perhaps I misunderstood one of your posts?
Didn't we put two rover vehicles (Spirit and Opportunity) on the surface of Mars, and 3 astronauts on the surface of the Moon? How hard is it to gently place a 1 MT nuclear device on the surface of an asteroid? The only major interplanetary vehicle landing problems we have had (Mars Polar Lander) was that the landing (retrorocket) parameters were specified (by Lockeed Martin) in English units, and the NASA people used metric units. So what is your concern?Joseph Chikva said:Simply. Bob states that kinetic hit would be ineffective and nuke blast yes - effective.
But he did not answer embodiment method:
• how to carry nuke charge to asteroid?
• at what altitude or after hit detonation should be? As I am afraid that if after hit, simply nuke device will be destroyed without detonation.
• Or there is planed to do as in Armageddon movie - to send two teams of oil well drillers on two Shuttles
Bob S said:Didn't we put two rover vehicles (Spirit and Opportunity) on the surface of Mars, and 3 astronauts on the surface of the Moon? How hard is it to gently place a 1 MT nuclear device on the surface of an asteroid? The only major interplanetary vehicle landing problems we have had (Mars Polar Lander) was that the landing (retrorocket) parameters were specified (by Lockeed Martin) in English units, and the NASA people used metric units. So what is your concern?
Bob S
We are planning a soil-sampling mission to an asteroid in 2016:DaveC426913 said:Our failure rate on getting probes to Mars is 50%, and that's a large, stable, relatively non-randomly-rotating target.
Except for the '92-93 Observer mission, all the http://en.wikipedia.org/wiki/Exploration_of_Mars#Timeline_of_Mars_exploration" with a successful launch arrived at Mars. I doubt the landing issues that plagued a couple of the missions are relevant to the delivery of a nuclear weapon targeted at an astronomical body with no atmosphere and negligible gravity.DaveC426913 said:Our failure rate on getting probes to Mars is 50%, and that's a large, stable, relatively non-randomly-rotating target.
Ok, thanks.Bob S said:Didn't we put two rover vehicles (Spirit and Opportunity) on the surface of Mars, and 3 astronauts on the surface of the Moon? How hard is it to gently place a 1 MT nuclear device on the surface of an asteroid? The only major interplanetary vehicle landing problems we have had (Mars Polar Lander) was that the landing (retrorocket) parameters were specified (by Lockeed Martin) in English units, and the NASA people used metric units. So what is your concern?
Bob S
mheslep said:...targeted at an astronomical body with no atmosphere and negligible gravity.
Hi Joseph.Joseph Chikva said:...And sure that momentum asteroid should acquire as result of nuke blast can be easily acquired also by kinetic hit as well. And it seems me as more easy, rational and reliable way.
Hi Bob,Bob S said:Hi Joseph.
If I work out my kinematics as proposed, the asteroid is slowed down by about 2 meters per second, which is about the minimum needed (corresponds to 39,000 miles per year.).
If a 10 tonne kinematic mass traveling 24,000 meters per second (relative velocity) hits the the 8.7 x 107 tonne asteroid head on, it will slow down the asteroid by only 0.003 meters per second. Not nearly enough. Do you agree?
Bob S
The record for the US shows otherwise, given a successful launch and given the probe doesn't have to landDaveC426913 said:I think you're making a mistake simplifying it. We're pretty familiar with planetary probe procedures and yet we still have a high screw up rate.
Why land a nuclear weapon on the surface, and why would the body's spin rate matter?We have very littel experience landing on small tumbling bodies whose orbits are not nice, neat and low eccentricity and whose delta v is quite different from Earth's.
mheslep said:... given the probe doesn't have to land
Why land a nuclear weapon on the surface, and why would the body's spin rate matter?
Bob S said:How hard is it to gently place a 1 MT nuclear device on the surface of an asteroid?
We can deliver lots of blast energy (nuke) but negligible kinetic energy to the asteroid. To slow down or deflect the asteroid, we need momentum transfer. So blast energy has to be converted to momentum. Newton says p2 = 2ME. So the blast has to move as much mass as possible.Drakkith said:So...you are saying we need superman then? Or a nuke.
mheslep said:What might be required so that the asteroid is fragmented into parts small enough to burn up in Earth atmosphere?
Bob S said:We can deliver lots of blast energy (nuke) but negligible kinetic energy to the asteroid. To slow down or deflect the asteroid, we need momentum transfer. So blast energy has to be converted to momentum. Newton says p2 = 2ME. So the blast has to move as much mass as possible.
Joseph Chikva said:Simply. Bob states that kinetic hit would be ineffective and nuke blast yes - effective.
But he did not answer embodiment method:
• how to carry nuke charge to asteroid?
• at what altitude or after hit detonation should be? As I am afraid that if after hit, simply nuke device will be destroyed without detonation.
• Or there is planed to do as in Armageddon movie - to send two teams of oil well drillers on two Shuttles
Joseph Chikva said:And sure that the momentum which asteroid should acquire as result of nuke blast can be easily acquired also by kinetic hit as well. And it seems me as more easy, rational and reliable way.
HowlerMonkey said:Your post stated what my earlier post stated and now you are adding an angle not mentioned in your earlier post where you attempted to correct me by restating almost exactly what I had posted.
This is called a spin.
Drakkith said:Even if the warhead was detonated on the surface of the asteroid only about half of the blast would be absorbed by it anyways. Detonating 100 ft above the surface would provide almost the same effect I think.
So, your statement is to explode nuke warhead carried on interceptor missile after hit?Morbius said:You carry it on a missile. The majority of the work is to get to Earth orbit. For the Moon mission, getting to Earth orbit required the large first and second stages of the Saturn V.
The energy to get from Earth orbit to the Moon was delivered by the relatively modest third stage.
We have missiles that can carry a multiple warhead payload to high, but suborbital trajectory. If we reduced the payload to a single warhead, we can send the warhead a great distance.
The distance is many miles. The optimal distance is a certain fraction of the object's "diameter". I don't think the warhead is going to be in danger of being damaged before detonation, and those warheads were made to be reliable.
Dr. Dearborn shows scenes from Armageddon in his seminars as an example of what NOT to do.
Dr. Gregory Greenman
Ok, thanks.Morbius said:Joe,
Kinetic kill vs nuclear weapon was very heavily studied by LLNL back in the 1990s.
The nuclear weapon can deliver orders of magnitude more energy than can a kinetic kill.
The idea is we want to change the orbit of the asteroid, and that takes energy. If the asteroid is large, we have no way with our chemical rockets to put enough energy into a kinetic kill vehicle to be able to deflect a very large asteroid.
Again, for very large asteroids, or very short time for deflection; the nuclear weapon is the ONLY viable option. It beats kinetic impactors, "gravity tractors"... hands down.
One of the other problems with kinetic kill is that many of the asteroids are what are called "rubble piles". They are not one rock, but a bunch of rocks held loosely together by mutual gravity. A kinetic kill will deflect the rock it hits in a rubble plie, but won't deflect the bulk of the others. The only force between the impacted rock and some of the others is gravity, and gravity is too weak for the short time scale to impart enough momentum.
Dr. Gregory Greenman
Joseph Chikva said:So, your statement is to explode nuke warhead carried on interceptor missile after hit?.
Joseph Chikva said:So, your statement is to explode nuke warhead carried on interceptor missile after hit?
If so:
• What deceleration that warhead will experience after hit before explosion?
• And admissible deceleration for reliable operation of mechanisms?
And I doubt that existing MCBMs can be used. I am sure that new interceptor should be developed. That would not be a problem on base of just today's technology. But that will be a new missile much more agile than MCBM.
Ok, Greg,Morbius said:Joe,
Not at all. You don't have to hit the asteroid. You want to explode it a few miles above the surface, so you arrange for the missile's trajectory to pass just in front of, or just behind ( depending on what new orbit is desired ) and you detonate the warhead at the proper time.
There's no "hitting" the asteroid involved.
Dr. Gregory Greenman
I know something about warheads, fuses, as well as proximity, point detonating, delay modes. Thanks.Drakkith said:As Morbius said there is no need to hit the asteroid. Current warheads are already equipped with the ability to detonate at different altitudes either based on time or proximity/impact. Actually, the cruise missiles I work on have impact fuzes in the nose for a ground burst detonation option. It is trivial to time the detonation right down to milliseconds or less.
Joseph Chikva said:Ok, Greg,
I understood that from your second another post. Thanks.
Very little amount of energy can be delivered in that case. Was that calculated?
From what do you get numbers?Drakkith said:Why would very little energy be delivered? I'd venture a guess and say that if you got really close you could get 40%+ of the energy of the nuke transferred to the asteroid.
If you have an interest you can estimate that on base of provided by me data.Drakkith said:Hrmm, I guess I should have been more specific. I meant that if a nuke is detonated above the surface of an asteroid, at least 50% of the blast will simply go into space above. The other 50% should interact with the asteroid somehow. I took 10% away simply because I don't think exactly 50% will hit the asteroid due to the altitude of the blast. Some should get radiated close to the asteroid but barely miss it.
Drakkith said:I'm not talking about the actual amount of energy absorbed or whatever by the asteroid. I'm just referring to the amount of the blast that should impact it. Please tell me someone understands what I'm saying.
An atomic/nuclear bomb in space is a type of weapon that uses nuclear fission or fusion to create a powerful explosion in the vacuum of space. It is designed to release a large amount of energy in a short period of time, causing destruction and damage to its target.
Yes, an atomic/nuclear bomb can be detonated in space. In fact, several countries have conducted nuclear tests in space, including the United States and the Soviet Union during the Cold War. However, the effects of a nuclear explosion in space are different from those on Earth due to the lack of atmosphere and gravity.
No, oxygen is not required for an atomic/nuclear bomb to work in space. These weapons use nuclear reactions to produce energy, which do not require oxygen. In fact, the lack of oxygen in space can actually make the explosion more powerful as there is no air to absorb the energy.
An atomic/nuclear bomb can have various effects on the environment in space, depending on its size and location. The explosion can create a shockwave that can disrupt satellites and other spacecraft in its path. It can also release harmful radiation, which can affect astronauts and other living organisms in space. Additionally, the debris from the explosion can pose a danger to other spacecraft in orbit.
Yes, there are international treaties and agreements that regulate the use of atomic/nuclear bombs in space. The Outer Space Treaty of 1967 prohibits the placement of nuclear weapons in orbit, on celestial bodies, or in outer space in general. Additionally, the Partial Test Ban Treaty of 1963 limits the testing of nuclear weapons in the atmosphere, outer space, and underwater.