Russia Plans to Save Earth From Rogue Asteroid

I do not understand Schweichert's opposition to diverting the asteroid, Apophis. Apophis is a near Earth orbit asteroid with an sufficiently low risk of becoming an Earth impactor. It also will have in 19 years (April 13, 2029) a near Earth rendezvous of about 37,000 kilometers. So we have time to modify the orbit and a relatively soon date to measure the effort. The orbit does not take it any where near the complex kinematics of the asteroid belt between Mars and Jupiter, so all changes will be attributed to the effort. With an average diameter of 0.27 kilometers, Apophis is not an insignificant mass to move. This sounds like a nearly ideal practical run before the real threat gets discovered.

Apophis won't be big enough to build Thistledown inside though.

As Founder of Transcendia, I strongly, firmly support the war on large flying space rocks.

In fact I myself declared war on Asteroids, and to a limited degree on Comets last April Fools.

While some of you may minimize the risk to Earth, of these things, and say that there is time to prepare for a certain hit, this point of view does not hold water with me, for this is some hard stuff to figure out how to do.

It is a good idea to do some experiments and practice.

Those who want to ridicule those who grasp the threat to us, and are willing to work to prevent our extinction, will not find favor with me.

Over and over till blue in the face I have said that this is the sort of work we know now is required of us.

If the Soviet Union had not put up satellites and put a dog and a man, and sputnik into orbit, the US would have sat around eating hotdogs at the fair, and admiring fin backed Chevys as if the world was nothing but an amusement park.

I like amusements and Disneyland as much as the next guy, but tell you all flat out that to become a Big Time Species, in a universe that is hostile to little creatures like us, we need to focus together to protect this little planet we have found ourselves to be blessed to enjoy, or endure.

While maybe the Russians sort of lost the Cold War, they have been leaders when it comes to outer space issues.

Every time some US spaceship goes to hell, the US has to hire out to the Russians to get to the Space Station, so I myself will not put up with insults or ridicule of their work in this area, and again mention as founder of Transcendia, support them, especially since I did declare war on Asteroids this year.

Wow, its nice to hear that its not the USA alone being the watch dog, and that there are other countries taking the proactive initiatives. All the power to them, as well as the publicity.

p911

I'm not very familiar with this, but even if Schweikert is right about Apophis itself not being a threat, it seems wrong to pass up on the opportunity to do a dress rehearsal for the "big one."

I have a feeling they will be surprise at the unanticipated results.

Finally we can test the joint US/Russian space defense system a.k.a. Star-wars!!!!!!!!!!!!!!!

That's what it was billed as right and while we're slicing space with lasers let's be rid of orbital junk too!!!

That's what it was billed as right and while we're slicing space with lasers let's be rid of orbital junk too!!!

oh yea

Half a century ago, a group of scientists proposed a nuclear pulse propulsion system which was called Orion. Their research showed that using very small, properly shaped nuclear explosives, single stage spacecraft of eight million tons or bigger could lift of from Earth to orbit, tour the solar system, achieve velocities in excess of .1C, and deflect asteroids. Sadly, this project was killed by fear and by politics.

The simple truth is that, unless an potential Earth impacting asteroid is discovered early, chemical rockets will not be sufficient to get to the asteroid in time or to deflect it. Nuclear pulse propulsion is the only system available to us that can get us there fast enough, and powerful enough to sufficiently deflect a large asteroid to avoid impact with the Earth.

For the last sixty years we have all but turned our backs on nuclear power because of fear. The time is long past that we began to explore this powerful technology. The real and imminent threat of a large asteroid impacting the Earth (and there are one Hell of a lot of asteroids out there that could) demands that we do so.

http://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)

gives some interesting reading on this.

In a similar vein, Stanislaw Ulam's "Adventures of a Mathematician" is a great read. He is credited with originating the nuclear propulsion idea.

I read the link and see where it goes.

Micro rocket tests may be of some aid, but the facts still point to Space Elevators as enabling most of what we need for a robust and usable near earth space infrastructure.

If I was to be directing Research and Development, I'd push for micro rocket experiments with the nuke rockets, and push for carbon nanotube development necessary to make the Space Elevators work.

What say you?

I haven't checked out the space elevator idea very closely, but I have a sneaking suspicion there may be obstacles that haven't yet been accounted for.

Even if it does work, I don't see how it will help all that much with asteroid interception. (That's just a first impression, though.)

Cheaper way to get stuff up there to work with.

Setting off nuke bombs from the surface does have some big risks.

Big obstacle so far seems to be light and strong ribbons or cables.

Carbon nanotubes are supposed to be necessary.

Can't build it up either. Have to drop it down.

For both any rocket and space elevators equatorial regions are best either for dead wind zones and spin sling.

Bhankii is good with this stuff.

AH aint bad either.

Pink and Jorrie likely have some insights.

Gentlemen, I completely agree that the skyhook is a far better alternative than any other for getting to high orbit. However, for a high performance rocket engine capable of getting to a potential Earth colliding asteroid, the only thing that has the capability to get us there in a matter of weeks instead of months or years is the nuclear pulse engine. This will continue to be the case unless and until we come up with sustained fusion or anti-matter engines, or figure out how to build a vacuum propeller.

Reality is that if and when we need to deflect an asteroid, which is what this thread is all about in the first place, we are likely to have a lot less time than we would need to get there using chemical engines and low energy orbits. And, we are going to need a lot more thrust to deflect an asteroid than anything less than nuclear pulse can provide.

And, beyond these purely physical concerns, there is the matter of politics. Our so called leaders have demonstrated time and again that they have little concern for longer term issues such as a potential Earth colliding asteroid that will not hit until after the next election. Nor have they demonstrated much love for space. So once again, by the time it becomes an issue, we are going to have months at best, not years, to deflect an asteroid. Which again means we are going to need the high performance that only nuclear pulse engines can provide.

So you claim DrMoose, that because you can think of only one method to meet your hypothetical scenario that no other method should even be attempted. I'm glad true science does not work this way. Regardless of how successful, impractical or plausible this Russian attempt to move a celestial body turns out to be, it will produce valuable information. This has never even been attempted before. Whatever the outcome, we will now have a guide on how much warning we'll need should we ever be forced to deal with a real impactor problem.

I think that it's wise to find out if their approach will work before it has to work.

Sir, I think it is at least possible that you misunderstand my position. I do not in any wise disagree with anything that anyone has said regarding any of this. I absolutely agree that this Russian attempt to alter the course of Apophis is a thing very much worth doing, and that it will provide valuable data, probably far beyond it's initial intent.

My point sir is that, based upon what I know of physics and in this case orbital mechanics, and what I know of the political process, when the time comes, and eventually it will, we will need to have this technology or something even more powerful available to us to do what will need to be done.

Well I'm beginning to think that you protest to much. First, until Russia makes this attempt, we will not have any idea what it will take to divert an asteroid given plenty of time. Second, if you look at the large number of asteroids tracked by NASA (near Earth or not) I believe that it is not very likely at all that a seriously damaging impactor will not be tracked long before impact is imminent. While there is nothing to prevent a new comet from the Oort cloud, or one of the residents of the asteroid belt to stumble into a trajectory that will impact us on the first pass. Certainly most impact trajectories will take more than one transit of our orbit.

So I say that it is much more valuable to invest in detection systems to give us more warning time, than any hyper-velocity approach. Particularly since a hyper-velocity mission will require hyper-deceleration to interact with the object, too.

So can every plausible impactor scenario be answered without hyper-acceleration and hyper-deceleration, certainly not. But by improving detection we will be making it less likely that we will be surprised by something we cannot effect. That is if the Russians find out that we can effect an asteroid at all.

So I say that it is much more valuable to invest in detection systems to give us more warning time, than any hyper-velocity approach.

I agree, but one of the positives of this situations is what can be learned off of it, as from my earlier post #5. Because since we are not on a limited time schedule to avoid grave danger. This will reveal proof (if carried out, of what not to waste ones time on)

And then focus on earlier detection and alliterative, without the debate of hyper-velocities possibilities, when a crisis like this actually occurs.

Hopefully the Russians will share the results............probally for a price......dam capitalists.

p911

Fred, Fred, Fred. Again, I do not disagree with you, but again I believe you are misunderstanding me.

First of all, the laws of motion and orbital mechanics dictate that if you apply force to any object, it's motion must change. It is quite beyond doubt that we can, or rather, Russia can in this case, alter the orbit of Apophis. Of course, that they will encounter the unexpected is also without doubt. The exercise is absolutely worth undertaking on that basis alone.

Second, I sincerely hope you're right about asteroids being tracked long before they can become a danger. However and to borrow a phrase, "it's a big-ass sky". Just watching the plane of the ecliptic is a huge undertaking, and the simple fact is that the United States congress has not allocated funding to the effort since 1999, when it gave NASA a grant of less then $2 million for the effort. Furthermore, Arecibo observatory, our best planetary radar site, is in danger of being closed for lack of funding. Can you assure me that other national efforts are better funded?

I absolutely agree that it is a good thing to invest in better detection systems, and to adequately fund the ones that we already have, but thus far, our tract record in this matter is rather poor. I for one remain cynical that it will improve.

You (and Phoenix911) continuously refer to "hyper-acceleration" and"hyper-velocity", but this is not what I am speaking of at all. Fast yes, but there's nothing hyper about it at all. A chemical rocket can provide us with a max of a few tens of kilometers per second, depending on the payload. However, in this scenario,it seems at least likely that we will need to get a fairly significant payload to the asteroid, and probably as quickly as possible.

The reality is that to get there in time and with enough payload to do any good is going to require a lot more than a few Gs for a few minutes. What will be needed is sustained accelerations, say a G or two for a period of hours or days. A chemical rocket can provide the necessary levels of thrust, but cannot sustain it for very long. An ion engine can burn continuously just about forever, but provides very little thrust. Which leaves us where?

My whole point simply that nuclear pulse engines are the only technology available to us that will be able to get us were we will need to go in the time we are likely to have and with enough payload to do the job. I hope I am wrong, but I just don't think so. History has demonstrated time and time and time again that it is the pessimist who assumes the worst that is consistently right. And this is just not something we can afford to be wrong about.

Hi,

I agree firmly with Dr.Moose that if we have to go fast we need some nuclear drive.

Maybe this is changing to some extent as soon as the Vasimir concept will be near useful implementation. And this will need a nuclear power-source to provide the electrical power for the variable ion drive.

I do not understand why we cannot use nearby encounters, sending a bunch of nuclear armed and chemically driven rockets head on to the coming threat. Maybe with one day delay from first to next to make sure that a failure is not dangerous.

The nuclear explosions (although there will not be a big mass to concentrate the pressure) will split any asteroid and divert the debris.

And the concepts of hollow charges adopted to nuclear explosions will not need much mass.

Only drawback is a few uncomfortable weeks to know if it works properly.

RHABE

Only drawback is a few uncomfortable weeks to know if it works properly.

Nothing like empirical information, but just a thought on a trial on a near-by encounter, the results turned out to be changing the trajectory to a direct encounter.

Bhankii and others helped me understand some of this last March.

We did not discuss nuclear powered rockets at the time.

However he and others did address the need for extreme speeds.

If in fact nuclear powered deflection missiles are the only sorts of missiles that meet the requirements then I guess we'll have to build them.

Bhankii said that there was really nothing on the shelf that would do the job. And I believe said you could figure 100 billion and ten years to come up with a workable system.

Generally the direct impact has been rejected as even if you break apart the Asteroid the pieces are likely to still impact.

Chrisg288 suggested a Moon based rail gun system.

The Seti project has had amazing success with finding and tracking Asteroids, along with scientists in Colorado, according to my memory. (My desk is a mess so finding last Aprils speech and my notes will take awhile.)

At any rate while there are obviously major challenges to be overcome in achieving a Planet Defense System, the good news is that it is doable.

Good answer sir! However, it is my belief that missiles fired from Earth are not going to be adequate. I believe that it is going to require human minds on station to contend with the situation. And placing human minds on station quickly enough, with the necessary equipment and the supplies to let them stay there long enough to do the job is going to require something with the performance of nuclear pulse engines.

An Orion ship could launch from Earth surface and get to Mr. Asteroid in a single stage and get there quickly enough and with enough payload to make the thing possible, and is virtually off-the-shelf. No other technology available to us can do this. Period.

Thanks.

I have tried to give credit to those who have helped me understand the issue.

I know that earlier when in the past I looked at the Orion type, nuclear powered rockets, I knee jerk rejected them out of hand, but may well be forced to change my views.

There are definitely a good number of issues to be resolved.

In particular while I think exploratory missions to the Moon and Mars, and further are wonderful and great, I do wish that "We" were more focused on a more robust near Earth Space infrastructure.

I do see great potential for the use of Space Elevators for creating that and hope that it actually does come about.

The energy required to launch space craft from the Earths surface is demanding.

The human body is not designed for living without gravity, and for us, a lot of short trips up to perform work, seems much better than attempts at extended stays.

Would be nice to be able to assemble something like what you say is required up there, instead of down here, though it is not yet easily possible.

Even if we did have the necessary technology and materials we'd still have to have better space ship fleets to build the Space Elevators, since you have to build down.

In the meantime if the nuclear pulse powered rocket is all there is with any potential for protection from Asteroids, what difference does it make if the scenario is that an Asteroid is headed our way and we need to use a perceived dangerous technology to counter it? -Could be a last hope situation whether you like nuke powered rockets or not aye?

Thanks Russell,

I think that I prefer a different method... (also mentioned previously) Going to the asteroid, and planting nuclear rockets to spin the asteroid tangentially, slowly increasing its axial rotation, until the strain exceeds the ultimate strength of the body (rock? ice?), and that the fragmented parts will then fly off on angles not intersecting Earth's path.

If the russians say they are modifying the path without Nukes, this seems to me to be one of the few methods available. It may take a long time to spin the asteroid up to any kind of speed, and as has been mentioned before... early detection is critical.

I've also put my rockets up on tall towers.. the extra leverage helps the axial rotation, and because there is no friction in this 'system', there will be no atmospheric effects to deal with. How much construction materials can we realistically get to the asteroid, and in what kind of time? I don't think this will be realistic for quite a while, until our space infrastructure is 100 times the size it is now... I believe we will find metals and fuels in the asteroid belt itself, and can establish processing facilities there.. but it will be a while... if ever.

Chris

An interesting idea, but there are a few things that trouble me about it.

First is that, in fracturing the asteroid in this fashion, one would need to know a lot about the structure and mass of the thing, which implies at the very least some rather extensive probe missions.

Second, when the asteroid fractures, the results are going to be chaotic. We cannot know in advance that none of the fragments will not still be on a collision course with Earth. And some of those fragments could easily be very large.

Third, the energy requirements to spin the asteroid up to a speed which would cause it to fracture could easily be greater than that required to deflect the thing.

Fourth, to assemble the necessary engines on the asteroid would require a much larger manned mission than to set up a single engine to deflect it.

Fifth is the time factor. Spinning up an asteroid is, as you have pointed out, likely to take some time. And the question that continues to come to my mind is, how much time will we have?

I do dislike sounding like a sample loop.

We cannot theoretically solve the impactor problem for every possible scenario. Particularly when we have yet to demonstrate a solution for any impactor scenario.

Hi DrMoose... some well thought out insights there.

It is probably worse, as the body may well be tumbling, and it would not be possible to figure the correct placement. Oh well.. guess we are screwed then..

I will disagree about it taking more energy to spin that to deflect... not that I've done the math, but... in my years of experience in Meteor Management, I have gained valuable insight that i feel is equivalent to all this scientific and mathematic psychobabble... Really it is instinct that counts.... my ancestors dna, with hundreds of thousands of years expererience, having survived the jurassic impact, has prepared me for this day... and I just feel the right answer. take that. Ha!

time for my medication... gotta go.

cheers!

Again Chris you come up with another great concept.

Possibly though the way to go for simplicities sake is to just get the thing to spin away, instead of spinning apart?

There is one significant advantage to your approach Chris, you don't have to figure out where the center of mass is and line up the engine thrust to it to prevent spinning. I wonder what the Russians plan to do?

I wonder what the Russians plan to do?

A smoke screen

The concept of altering this asteroids course scares me slightly, what if we alter the trajectory such that it becomes on a collision course with earth. It may seem like hiding under the bed, but the best course of action may be to leave it alone.

I do understand that the threat of asteroid collision with earth is quite serious, perhaps it would best be performed on a one time fly by asteroid and observe the altered course, rather than one that continuously comes close to us.

Astronomical decisions like this should be made by a higher authority than one nation's head of state, board of representatives, etc.; all the risks should be assesed prior to testing. This reminds me slightly of something uttered to me once, that when the first nuclear bomb was tested that someone stated that there was a remote possibility that the explosion could ignite the atmosphere, and in response it was uttered that that would be a better outcome than the enemy doing it first.

I suggest that if Russia truly want to test this that other nations (representatives) be made fully aware of the procedure to ensure that there is no doubt about the necessity for such measures. Perhaps we need another body or affiliate body of the UN formed as a scientific council to discuss and deliberate global matters of this magnitude and make the necessary decisions that we as individual nations are incapable of making or refuse to make.

I perceive the Guest to be practiced at meaningless gobblygook.

Case 1: The asteroid is actually on a collision course with Earth. Diverting it is a necessity.

Case 2: The asteroid is not actually on a collision course with Earth.

a) Leave it alone, and let it go by. No problem.

b) Fail to realize realize this, and divert it. Most diversions will take it even farther away from Earth, but one specific diversion (correct angle of diversion and correct location on the resulting cone) will collide. The chance of this is very low.

To put it bluntly, there is only one way to hit a target, versus a gazillion ways to miss it. Switching from one of the gazillion ways to another will still most likely miss. If you want to be a worry-wart, pick something better to worry about.

Gentlemen, in all fairness, this guest does raise a valid concern. The possibility, however slight, exists that we might change the orbit of a near Earth object into something a lot more serious. There are a lot of factors involved, and we cannot say with absolute certainty what will happen once we begin. Indeed this is why we need to give this thing a test run in the first place!

Beyond that, okay, I don't agree with anything he says either, nor am I at all certain he has any idea what he's talking about.

Precisely my point that Apophis is an ideal candidate. With a near Earth trajectory in nineteen years this gives us (excuse me) the Russians plenty of time for a robotic rendezvous, time to implement an orbit change and then make a coarse measurement of the effect if any. If the coarse measurement implies an increased impact risk instead of a decreased risk, we will now know how to alter the orbit by changing the process. While this might require a new robot with more fuel (nuclear, chemical, extra solar panels), larger solar sail material or another expended material; there will be time to respond.

A critical detail that people have overlooked, Apophis and the Earth orbit in the same direction. While this does mean that our relative velocities will be low, this is not my point. We will have several not as near crossings that permits these reasonable measurements, and more importantly ease in a successful rendezvous.

Once we find out if we can move and not just fracture a massive object in space, we can worry about how to quickly get to a more difficult trajectory asteroid if it ever comes around before we naturally do ourselves in. To worry about how to quickly get to an impactor asteroid/comet that has yet to be noticed, without a proven method to change the direction of its movement is like hiring an account to manage your Lottery winnings before buying any Lottery tickets.

*Gentlemen, in all fairness, this guest does raise a valid concern. The possibility, however slight, exists that we might change the orbit of a near Earth object into something a lot more serious. There are a lot of factors involved, and we cannot say with absolute certainty what will happen once we begin. Indeed this is why we need to give this thing a test run in the first place!

*Precisely my point that Apophis is an ideal candidate.

Ugh! The logic doesn't persist using a large object to demonstrate the probabilities of risk. We They could microwave the object then crack like an egg

*With a near Earth trajectory in nineteen years this gives us (excuse me) the Russians plenty of time for a robotic rendezvous

Or to orchestrate an elaborate ruse.

Actually I myself am not so particularly concerned with Apophis, as itself being this terrific threat, but more in support of "Us" developing and having the capability to defend the planet from the threat, which is real.

It was impressive that Seti and those guys in Colorado did find a right small Asteroid on its way, predicted it would hit, and even where it would, then it hit, and they found the pieces.

Actually the title of the thread is apropos for using the adjective "Rogue", for in nature, out at sea, every now and then even the hugest of ships have encountered rogue waves totally unanticipated.

For governments border defense is a legitimate thing to take responsibility for, so it is responsible and legitimate for Russia to undertake a defensive program in anticipation of such a threat that asteroids do represent.

Possibly they are influenced by the reality of such a possibility demonstrated by the powerful explosion attributed to such a body that did take place within their borders of Siberia not that long ago.

Hi,

in this discussion I do not understand:

A.: why there is speculation about nuclear pulse engines that may never come into existence or usefulness?

Stay with todays technology, maybe you/we have to act tomorrow!

B.: who is ever thinking about a "space elevator" will ever be a reality?

The maximum length that can support its own weight is ...

The strongest available steel has a (rupture) strength of near 3000N/mm² and this is usable to may be 2000N/mm², so a cable of 25Km length will break at its own weight.

With best available silica fiber this may be a factor of 2 in strength times a factor of 3 in density so 150 Km,

with carbon fiber the situation is the same, with carbon nanotubes it may be a bit better in the near future.

So maximum available height is 75 Km with some weight to be transported up.

Calculate the drag and the necessary velocity to stabilise this attachment to Earth!

A near surface satellite that is stable by balancing the centrifugal force with the gravitational force has a period of 84 minutes. So how will you prevent your elevator construction to fall down to Earth again with nearly no centrifugal force???

Never you will go up there by elevator! Forget your dreams and Star-trek fairy-tales and come back to reality.

Reality is: 5 or more states today have the possibility to send (big and multiple) nuclear warheads with yields of 0.4 to above 10 M-tons of TNT equivalent halfway around the world.

By slight modification and restriction to 1 warhead only - likely mounted on a second stage - this can be ready within 6 weeks to 6 months - any of the components is existing.

IMU guidance and control would have to be reprogrammed and supported by a sun- and-star-sensor, to give orientation for some weeks. Available from many interplanetary probes.

Final steering and control has to be added by an automatic or semi automatic system that is very likely available from some of the cruise-missiles programs.

Blasting the warhead at 1 million km distance will need a start 1 day in advance - only!

If a head-on collision is planned and the blast shall occur near the surface then the trigger shall act some few microseconds before touchdown - this is coarse in electronics and was possible 1945!

If pass-by and explosion at nearest distance is planned (to bring the beast out of the ecliptic plane this should be done above or below the plane of the Earth's orbit) with near 10Km/s velocity and 100m length of the "beast" the + 10m will translate to +- 10m-seconds! Not at all a problem!

So there may be the problem of one or more of the rockets are failing at start - the warhead disarmed at that time will be a problem if too much Plutonium is dispersed in the atmosphere, not likely as designed to survive soft impacts, but may be severe contamination of the impact on the ground. This problem has been solved at earlier accidents.

So in total:

If ample time is available, bring a nuclear reactor and an ion-drive to the beast and deflect it until no more a problem. (Will need many months and may be years).

If a few days are available to react the only possibility this ICBM modified to single warhead will do the job.

In order to be effective it is a necessity to have an estimate of the material of the beast, metallic is much more difficult than stony and or icy.

Anything else are accumulated dreams triggered by SF!

RHABE

When we went round on this subject back in March and April of last year, I tended to agree with Bhankiii that nothing really was in place, and off the shelf available to do the job.

I believe at the time that you had some influence, but am not certain that cleavage to past developed tech is appropriate to this particular task.

I was hopeful that some off the shelf stuff could be parked in orbit, but looked like after discussions, this was not practical.

Bhankii has not shown up to this particular thread.

As I remember last time we went around on this both you and Bhankiii did influence my views.

Are you saying that you could put together a Planet Defense System within a year with available off the shelf rockets and guidance that would work without experimentation and tests on asteroids that even if deflected would be very unlikely to according to the law of unintended consequences to constitute out of that, a threat, since they are not particularly a threat as they are now, but represent in general threat as a type or threat?

Damn. I haven't written such a long sentence and allowed it to stand, in a long time!

"Are you saying that you could put together a Planet Defense System within a year with available off the shelf rockets and guidance that would work without experimentation and tests on asteroids"

With the help of joint US, EU and Russian and Chinese knowledge, yes.

Any of these states could do the job, but as nuclear warhead transportation is involved, I see a need of joint action.

"even if deflected would be very unlikely to according to the law of unintended consequences to constitute out of that, a threat, since they are not particularly a threat as they are now"

would be either crashed into very many pieces - some may hit Earth later but not very many - or deflected out of the Earth's plane of orbit, so crossing this plane only twice per asteroids orbit, so within this 1 second a hit may be possible with a probability of 1 s/(365x86400)s or near 1:30 million.

Better - without any doubt would be a long lead time and a deflection approach with an ion thruster. But this would require an experimental nuclear reactor and a lot of time. Thrust from ion drives is low but continuous. So the same discussion about transporting highly dangerous material to space would be started.

RHABE

I do not expect any danger from space within the next 1000 years. But I do expect a lot of dangers from stupid or corrupt or fundamentalistic men and women every year.

Thanks for taking a look at this Bhankiii. I value your opinion.

You raise a couple of good points, at least.

Further you do offer some possible solutions while maintaining a certain scepticism.

I respect Rhabe's opinions as well.

Overall I still feel solutions to the problem, while daunting, are called for.

Last time we visited this subject I had fallen down to imagining multiple rockets parked either in orbit, or on the Moon. This might address the problem of attempting to make one size fits all point you make concerning the various possible sizes of the Asteroids.

Just as a battlefield commander typically does not rely solely on infantry, and Air Forces will typically employ more than one sort of aircraft, I suspect that similar redundancy, and coordination of different systems is really required.

I have also come to feel, that while trips to Mars etcetera are wonderful, overall we Earthlings need a more robust near earth space infrastructure, as if doing things in order builds capabilities presenting possibilities otherwise harder to fund, or justify for threats viewed as minimal.

While we have apparently not so much to fear of the known asteroids, I find it hard to believe that there could not be a rogue, same as their have been rogue waves in the oceans. Among ourselves there have been instances of the Sneak Attack.

Of technical problems related to deflection, which is more recommended than smashing into an asteroid, I have imagined spinning deployment of what are essentially grappling hooks, nose deployed blunt trauma nets, pass by rockets that fire out their ass landers that redirect the asteroid.

The ideal is that since the threat is somewhat minimal, but does exist, whatever system we do come up with, can be integrated into systems that have more than one purpose, same as we have developed fighter bombers, C130 gunships and rockets that have put either people, or satellites in orbit.

Sir, while you make some very good points, I must disagree with you on a few points. You see, if and when the issue arises, as it almost inevitably must, doing it will be a matter of life and death.

The facts circa 2010 are as I've already said, but I'll say them again. Sky tracking efforts are very poorly funded at best and almost certainly will remain poorly funded. Space missions are also poorly funded, especially compared to the Mercury, Gemini and Apollo programs of the 60s, which is why new missions take 5-10 years.

Now consider what seems to me to be the most likely scenario. Nothing is going to be done over the next few years to invest in new detection systems, near space infrastructure or space-craft. So at some point over the next few years or decades, somebody, most likely an amateur with a small telescope, will discover a new object. It will then be observed and tracked and will be determined to be the size of Ceres and on a collision course with 388 days to impact (just for example).

So, there we will be, with one hell of a big rock heading our way and only slightly more than a year away. There will be no time for a probe mission to determine it's exact mass, composition and structure, which will make it impossible to develop a robotic mission to deflect or fracture it. To deflect it will require a massive mission to put men (and maybe women) on station to evaluate the situation and decide what to do about it, and then have the necessary stuff on hand to deflect the thing, so that the entire planet doesn't end up like a melon hit by a canon shell. It will be a matter of life and death for the entire planet and we will have neither the time to be timid nor the option to not get it right the first time.

So what are we to do in this situation? Obviously, money is not going to be an issue, nor is manpower. First of all and as I've said already, neither chemical nor ion propulsion is going to be enough to get us there. Nor are we going to have the luxury of engineering the thing to the point of zero risk. We are going to have at most perhaps nine months to build and provision a ship and get the mission on station at the asteroid. And I remind you that it's almost certainly going to have to depart from Earth surface. Whether we like it or not, only an Orion will have the sheer power to get the mission off the ground and get it to the asteroid in time.

Now, you say that an Orion is a pipe dream. I beg to differ. Both the physics and the engineering are pretty well worked out and understood. We also know a heck of a lot more about nuclear explosives now than we did half a century ago. And with an unlimited budget and all the manpower of the entire world, it is the only kind of spacecraft that has any chance at all to get there in time and with enough payload to do the job. Nuclear pulse propulsion is also the only thing that's going to have enough power to deflect such a rock in the time available. It's also all but off-the-shelf.

Now, I will grant, with a smaller asteroid and a lot more time, it might be possible to plan and execute a robotic mission using chemical and/or ion engines, but only if it's a fairly small rock and if we have a lot of time.

I might add that I agree with you about a fracture mission. Even if we were successful in shattering an asteroid into a gazillion pieces, those pieces will still be gravitationally bound to each other and to the collision course. It looks to me like the difference between a canon shell in the chest and a face-full of buckshot.

Now, I know that such a thing has never happened in recorded history. But it is all too likely too happen, and the next half century or so is a critical time, when we have the technology to defend ourselves from this threat, but not the emplaced infrastructure to help us deal with it. Never-the-less, I have faith in my fellow man. Humans are selfish, self-centered, deceitful, etc. But we are also unlikely to lay down and die in the face of any threat, this included. Even knowing that there would be zero chance of making it back from such a mission, there would be no shortage of volunteers, myself included.

Dear DrMoose,

Though there is no direct precedent as if to say we have in the past though our actions and technological prowess prevented an asteroid strike, there is likely to exist a precedent for identifying a threat, and countering it.

In regards to WWII the Manhattan Project is often called up as the sort of program needed to obviate the US failure to secure energy sources within its controllable borders.

I shall look at the programs and personalities that allowed the Dutch to prevent their nation to be put under the sea, to see if that history applies as a precedent.

That precedent is of greater interest since it involves a struggle with nature, whereas the other precedents come from war amongst ourselves.

You bring up another point that shows why Apophis is a good experimental candidate. Apophis has for it's apogee an distance from the sun not much farther than the Earth's nominal orbit. Thus the orbital velocity will not be much more significant than ours. So Russia's probe will not require as significant a change in velocity to be captured or land on Apophis. Possibly most of the change in velocity could be by using the moon's gravity well and momentum.