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According to some experts, since it is inevitable that an asteroid or meteor will hit Earth, the U.N. should do something about it

Due to the threat that an asteroid named Apophis poses to the Earth, a group of astronauts, scientists and engineers want the United Nations to have a plan for killer asteroids.  A UN treaty draft dealing with the complicated yet unlikely issue will be drawn up before the end of 2007.  Topics covered in the draft include who would be in charge of deflecting or destroying objects that pose a threat to the planet.  For example, the U.S. Congress has assigned NASA the roll of actively searching for objects that are considered threatening.

Apophis is traveling around 28,000 miles per hour towards Earth, and could hit the planet sometime in 2036, warn space professionals.  Astronomers who are monitoring the asteroid admit that the chances of impact on Earth are extremely low, but recommend proper scenarios should be planned in case it does near Earth around 2036.  

Some experts have vehemently warned that it is only a matter of time before an object such as an asteroid or meteor strikes Earth.  NASA astronaut Edward Lu has gone as far as telling NASA that it should send out a spacecraft designed to be able to attempt to divert asteroids.

NASA is currently monitoring 127 near-Earth objects (NEO) that could pose a threat of hitting the planet.

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Cost
By jodhas on 2/20/2007 4:10:06 AM , Rating: 3
Due to the creation of powerful telescopes, we can spot NEOs many years before impact or near impact.

Taken from Wikipedia
"Additional observations through 2006 resulted in Apophis being lowered to Torino Scale 0 on August 6, 2006."

The chance of the asteroid hitting the earth is pretty darn slim.

So here is the big question...
Who is willing to dish out billions for something that will never see the light of the day? I just hope and pray it isn't our government.




RE: Cost
By DOSGuy on 2/20/2007 4:44:37 AM , Rating: 4
Apophis may not be the one, but we don't know yet know how much time we have before the next impact. It's always a good idea to be prepared. Scientists and engineers warned of the threat that hurricanes posed to New Orleans for years, but governments didn't think they could justify the expense of protections that might never be needed. By the time a disaster was on its way, it was too late to do anything about it. In hindsight, we're outraged that our governments didn't protect us. How enraged will we be if government inaction allows millions to die?


RE: Cost
By Moishe on 2/20/2007 8:20:30 AM , Rating: 4
I think this is fear mongering. I will not live in fear of something I can't see coming or something I can't stop from coming. I am certainly not outraged when the government doesn't protect me from natural disasters. The government is not my babysitter and I'm no child. If I die, I die. I think it's pretty foolish to spend a lot of money to protect against an event where the odds are so huge against it ever happening. It's like the odds of winning the lottery. I think the world should slowly develop something *together* and eventually they'll have something.

I wouldn't spend a cent to protect from being hit by a random bullet. Why? Because the odds are so low it would a waste of money. You'd laugh at someone who wore a bullet-proof vest all the time. They'd seem paranoid. Why? Because most of us will live for 80 years never once being shot at. It's the weirdos and kooks that people laugh at for owning gas masks and bomb shelters.

The government or the UN cannot protect us from natural disasters, and if we give them our money, they'll waste it with fraud like they did with the Oil-For-Food program.

I wouldn't give a red cent to those corrupt bastards if I had a choice.


RE: Cost
By masher2 (blog) on 2/20/2007 8:36:19 AM , Rating: 4
> "I think this is fear mongering..."

Massive asteroids have hit the earth before. They will do so again-- this is mathematical certainty. Not "fear mongering".

In any given year, the chances of it happening are very low, true. So while it's not practical to spend hundreds of billions of dollars until we see a more verifiable threat, a more modest (read "cheap") program of detection and planning does make strong financial sense.


RE: Cost
By jtesoro on 2/20/2007 8:58:40 AM , Rating: 2
Someone who worked in a government program about the asteroid threat has posted in DT before. If I recall correctly, he said something like: "The risk of an asteroid hitting the earth is real and measurable. On the other hand, I'm not losing any sleep over it."

I don't know how much money is spent in this and similar programs, but it seems there is at least some effort being put in to address the potential threat.


RE: Cost
By masher2 (blog) on 2/20/2007 9:16:21 AM , Rating: 3
I'm not losing any sleep over it also. I don't lose sleep over the possibility of my house burning down or my cars being stolen...because I have an insurance policy.

That's all that's being asked for here. Not hundreds of billions for a space-based force. Just a few million for planning and preparation. Cheap insurance.


RE: Cost
By Moishe on 2/20/2007 9:29:58 AM , Rating: 1
If you believe "just a few million" then you're naive... and I know you aren't that naive.

If the UN or even the US government were to spend any money at all on planning to deflect/protect against asteroids, a few million will cover only the first 2 months of planning, if that.

We are talking about billions in the long run at the very least. Bombs aren't cheap, space vehicles aren't cheap, and bureaucracy is wasteful.

I think a reasonable commonsense response is something like $100 mil each year split equally by all members of the UN Security Counsel. Set goals, make plans, implement small pieces, and build on it. In 10-50 years you'd have spent 1-5 Billion and produced a working plan with proven and tested hardware.

The problem here is that government is incapable of making plans and sticking to them,


RE: Cost
By masher2 (blog) on 2/20/2007 9:42:45 AM , Rating: 2
> "We are talking about billions in the long run...I think a reasonable commonsense response is something like $100 mil each year ..."

Are you hearing what you're saying? $100M/year IS billions in the long run. Within a decade, in fact.

I have to point out that what the ASE is asking for is actually substantially cheaper than $100M annually. They want an international treaty for cooperation, increased monitoring of NEOs, and some initial feasibility studies on deflection. That's it...an annual cost less than half of what you yourself say is reasonable. So where's the beef?


RE: Cost
By timmiser on 2/20/2007 4:17:35 PM , Rating: 2
I don't think you heard what he said. I believe he was merely backing up his statement that it would in fact cost billions in the long run by costing 100 mil a year for planning, etc.

Regardless, I think it is imperative to any statement or comment to define "planning". If it means dialog and a few reports/essays on what we could do, then it shouldn't cost that much. If planning actually means design contracts, prototypes, testing of hardware, than yes, it could cost that much.


RE: Cost
By Martin Blank on 2/20/2007 11:32:42 AM , Rating: 2
Bombs? If you think that bombs are the answer, you're not very well versed in this. Bombs have a high potential of just making a bunch of smaller units that are harder to track and potentially scatter the damage across the entire planet.

One of the top two ideas involves painting the asteroid with white paint to allow photons bouncing off of it to alter its course. The other involves putting a weight of a few tons in a parallel orbit, allowing gravity to work to pull the asteroid to a slightly different orbit. This may not seem like much, but every cm/s change in direction alters its location by 315km each year.


RE: Cost
By rtrski on 2/20/2007 2:12:39 PM , Rating: 2
You've got to be kidding me: "put a weight of a few tons in a parallel orbit, allowing gravity to work..."

How, exactly, is expending all the propellant to get a near identical orbit out of a FEW TON MASS going to be more efficient than attaching a thruster to the asteroid itself and expending the same propellant (plus the 'few tons' you no longer have to ship out there) to deflect the asteroid directly?

And if you respond that the asteroid may be 'orders of magnitude bigger' than the 'few ton mass', your 'few ton mass' would not gravitationally deflect it, anyway.


RE: Cost
By masher2 (blog) on 2/20/2007 2:29:45 PM , Rating: 2
> "How, exactly is [this] more efficient than attaching a thruster to the asteroid itself..."

It's not. However, a thruster attached to an asteroid has to exert its momentum vector at a single point. Most asteroids don't have the tensile strength for this to work.

Here's a useful analogy. Consider a enormous ball of dust in space, held together by nothing but its own gravitation. Now, glue a rocket motor somewhere to it, then turn it on and see what happens.

Now, your average asteroid isn't quite that friable...but some of them aren't far from it. And all it takes is a small shifting of the asteroid's center of mass under acceleration, and suddenly your thruster isn't pushing it away from the earth, but rather towards it.


RE: Cost
By rtrski on 2/20/2007 8:12:35 PM , Rating: 2
Sorry, that argument doesn't wash either. Yes, I said "thruster" singular...my bad. I figured anyone reading could understand I meant a propulsion system, knowing full well that the thrust would have to be distributed over a surface (probably many small thrusters) as well as kept low to avoid breaking the asteroid. You want the total thrust vector to exert against the center of mass...doesn't' mean you're forced to a single thruster pointing along that line. Is the shuttle engine designed that way, as a single big cone pointed at one point? No, because the structural framework and load-distribution of the shuttle was designed to transfer loads. One would certainly need to evaluate the asteroid's cohesion and center of mass vs. its volumetric centroid - effectively its own 'load transfer' dynamics and stress/strain handling ability. But this could all be done by placing multiple thrusters on a central control, ramping them up slowly and monitoring resulting spin/momentum changes until a viable concerted effort was generated. In fact since the asteroid probably has a spin to begin with, one probably needs an orchestrated thrust from a skien of thrust units distributed all the way around it, turning on and off as the appropriate surface normal points in the direction away from which you want to move. There'd be no sense in expending propellant to de-spin it first.

As for 'shattering' the asteroid, all you have to do is keep the net thrust below the self-gravitational value of the asteroid itself. Forces a (milli- if not micro-gees) low acceleration, but that's what you'd be stuck with anyway with any system (ion, etc.) you could get out to interplanetary space with enough propellant to do anything with.

If it was friable enough to represent a dust-ball, it *would* be 'explodable' after all, not to mention extremely likely of breaking up from tidal forces if it was coming in on anything other than a perfectly targeted trajectory, or breaking/burnin up *significantly* due to internal outgassing and friction/drag on atmospheric entry immediately following. Would still do some (potentially significant) damage to the atmosphere, but kind of rule out a deep crater impact....

Tunguska was estimated as being one such 'puffball'. Felled trees, left a crater...but no where near the size/depth it should've been for a solid mass of the size they guess it was from the energy released.

Bottom line is: the 'accelerate a huge mass to parallel orbit' answer just makes no sense. All you're doing is having to engineer something that itself behaves like a 'rigid body' despite massing enough to have a gravitational attraction on the asteroid, and then handle all the delta-vees to get it out there and turned around into a parallel orbit, which means you're putting it into pretty much the same collision trajectory. And if you screw THAT up...you just increased the incoming danger.

Frankly the 'paint' idea isn't that great either...it'd take some serious surface area for albedo changes to make a difference. But extending a light sail (would also have to be tethered to the asteroid in such a way as to not break it and "tug on its center of mass" in net effect) might, so I let that one slide originally as the right idea at least.


RE: Cost
By masher2 (blog) on 2/20/2007 11:27:59 PM , Rating: 2
> "Yes, I said "thruster" singular...my bad. I figured anyone reading could understand I meant a propulsion system"

One thruster, multiple thrusters, it doesn't make much difference. They can still only act against a limited number of surface contact points...a surface that is, for most asteroids, too brittle and friable to withstand anything but the faintest of forces.

A gravity tractor, now, works against the entire volume of the asteroid. And, compared to a large network of anchored thrusters, is much simpler. Just plot a near intercept to the asteroid, then keep a parallel-but-slightly-diverging course heading over a few years time. It can be done totally remotely, without the need for humans (or robots) to attempt a surface landing to mount and position any hardware.

You're welcome to disbelieve me if you wish, but any expert on the subject will tell you the same thing. I'm not exactly breaking any new ground here.

> "the 'accelerate a huge mass to parallel orbit' answer just makes no sense..."

I think you're misunderstanding the amount of mass required. A few tons is all that's needed. Yes, its gravitational influence on a multi million ton asteroid is near-negligible. But that influence working over several years is all thats needed to avoid a collision.


RE: Cost
By Pirks on 2/20/07, Rating: -1
RE: Cost
By masher2 (blog) on 2/20/2007 4:50:44 PM , Rating: 3
In the absence of gravity and a containing atmosphere, the shock wave of an explosion is quite different than here on earth. Look at my "dust ball" post to see why a DU interceptor (or a nuclear bomb, for that matter) is unlikely to work against an asteroid target.

A gravity tractor is a much more reliable method. Just position a semi-massive satellite near the asteroid. Then, over a few years time, slowly use the gravitational attraction between the two to modify the asteroid's path.


RE: Cost
By Pirks on 2/20/07, Rating: -1