Expert: Philip Stahl - 12/16/2008

Question
I was reading through some recent answers and am somewhat confused. Do we have anything, any sort of protection against oncoming asteroids? Some other expert (I think, Tom Whiting) said that "liberal democrats" killed the Reagan Star Wars program and that would have done the job. Is that true? I thought it was just a big white elephant and had little scientific backing.

Also, what about global cooling? Real or not? More critical than global warming now or not? Any light you can shed would be nice!

Answer
Hello,

The Reagan “SDI” (‘Strategic Defense Initiative’) wasn’t killed by any such critters as “liberal democrats” but by its own stupendous weight of nonsense, bunkum and infeasibility! This was known as early as June, 1985, when physicist Wolfgang Panofsky wrote one of the most brilliant demolitions of this farce, appearing in the June (1985) issue of Physics Today ('Strategic Defense Initiative: Perception Vs. Reality', p. 34). Panofsky, then Professor at the Stanford Linear Accelerator Center, noted that Reagan’s half-baked boondoggle was “too large, too political, raises false hopes and poses grave dangers to national and world security”.

Barely two years after Prof. Panofsky’s takedown, the American Physical Society published its ‘Directed Energy Weapons Study’ (Physics Today, May, 1987) and finished the job. It was by then evident to anyone who could read that the ‘Star Wars’ program was merely a giant fiscal black hole for public money that could be much better spent many other places. (For example, sustaining and maintaining our infrastructure!)

If you can get hold of that issue, please do read the report, OR try to get Prof. Panofsky’s superb book, ‘Particles and Policy’(1993) which goes into detail on why and how the whole thing was unworkable. For example, on page 81, in conjunction with the SDI’s supposed particle beam capability, he notes that:

“When a beam of particles strikes a stationary target at least half of the energy of the incident particle is used to move the center of mass of the two colliding particles ahead, while only the remaining fraction of energy is available for the collision itself”

In terms of the purported lasers sported by SDI vehicles, it was also noted that even the most powerful laser beams at the time wouldn’t be able to knock down a missile launched in the boost phase and returning at 18,000 mph. The cross-sectional area (and energy) diffuses too much to be of use, and all the tests showed the kill vehicles missed by wide margins in any case. (The SDI hotshots did manage to shoot down one harmless little solar survey satellite for target practice- which had nada to defend itself, not even the millions of  metallic pieces that an incoming missile would normally use as false targets to misdirect kill vehicles)

To think that any SDI vehicle could have taken down a large asteroid coming in at over 40 m/s is preposterous. The stuff of fairy tales and perhaps…..too much fantasizing. No way, and no how would any of Reagan’s toys have been able to achieve that, even if we’d have poured tens of billions more into that money pit.

However, it is true that a mainly Republican Congress (from 1993 on) did kill efforts to adequately fund NASA research (in Project "Space Watch”)  to do with just monitoring the Near Earth Objects – including wayward comets and asteroids. It was said at the time, as I recall, that there was just “too high a chuckle factor associated with it” and hence, the dignified reps might feel like clowns had they obliged.

Project Space Guard is now the de facto asteroid defense program in waiting and you can read more in a previous answer I gave already on this site three years ago:

http://en.allexperts.com/q/Astronomy-1360/asteroids-comets-1.htm


You can also check out, if interested:

Space guard Foundation:

http://www.cfa.harvard.edu/~marsden/SGF/


I would think that any reasonable approach here would probably have to make use of a number of nuclear missiles fired at the oncoming threat – and then we’d have to hope it isn’t TOO large! For example, while a squad of 10 or so ICBMs may be fitted to take down a 1 kilometer object, a five km diameter one (or planet killer) would be a lot more dicey. Further, even if you hit it soundly, there is no assurance it wouldn’t break up into about ten half kilometer objects to clobber different Earth locations. But then, this would likely be more tolerable than one single hit from a five-K monster!

My point is SDI would not have added anything to what we already have the capability of doing – IF world governments can come to terms with a plan.

Now, as for global cooling and all the hoopla about that, let me say it is largely the result of one ‘Nature’ paper (Keenlyside et al, 2008) that has been totally misread by the media gurus and with the wrong conclusions drawn.

The errors are too numerous to recite here, but they are listed and explained in detail at this site for ‘Real Climate.Org’ where real climate scientists make their contributions – as opposed to climate skeptics and scientist wannabes:

http://www.realclimate.org/index.php?p=565


A key point is that the authors’  'cooling forecasts' have not passed the test for their hindcast period.

As a member of the AGU (American Geophysical Union) – their position is well-known and has been formalized in a position statement you can read here:

Human Impacts on Climate Change:

http://www.agu.org/sci_soc/policy/positions/climate_change2008.shtml

Nothing has changed in terms of the data to force an alteration of the above, and indeed, most of us expect this “cooling” period (if even real- and it must be confirmed first!) will not last very long, probably not beyond 2010 before things heat up mightily again.

The best thing to do in the meantime is pay attention to the sources offering the information. Most of these are crypto-libertarian or plain unadorned libertarian who aren’t the least invested in the genuine science behind the well-tested IPCC models, but in preserving their last remnants of high growth capitalism.