California Professors Unveil Proposal To Attack Asteroids With Lasers 161
An anonymous reader writes "Yesterday's twin events with invading rocks from outer space — the close encounter with asteroid 2012 DA14, and the killer meteorite over Russia that was more than close — have brought the topic of defending mankind against killer asteroids back into the news. The Economist summarizes some of the ideas that have been bandied about, in a story that suggests Paul Simon's seventies hit "Fifty Ways to Leave Your Lover": Just push it aside, Clyde. Show it the nuke, Luke. Gravity tug, Doug. The new proposal is an earth orbiting, solar-powered array of laser guns called DE-STAR (Directed Energy Solar Targeting of AsteRoids) from two California-based professors, physicist Philip Lubin (UCSB) and industrial statistician Gary Hughes (Cal Polytechnic State). Lubin and Hughes say their system could be developed and deployed in a range of sizes depending on the size of the target: DE-STAR 2, about the size of the International Space Station (100 meters) could nudge comets and asteroids from their orbits, while DE-STAR 4 (100 times larger than ISS) could evaporate an asteroid 500 meters in diameter (10 times larger than 2012 DA14) in a year. Of course, this assumes that the critters could be spotted early enough for the lasers to do their work."
Why lasers instead of mirrors? (Score:5, Interesting)
Wouldn't it be much more efficient (and cheaper) to just use mirror arrays to focus the sunlight directly, rather than use expensive and inefficient solar panels to process the sunlight into a laser first?
Then, instead of sitting uselessly in space 99.999% of the time (or maybe 100%, even), they could focus sunlight onto ground-based power stations (or space-based, if we actually get mining operations going up there), and help pay for themselves.
It would also be a bit harder to weaponize. A DE(ath)-STAR in orbit? What could possibly go wrong?
Re:Why lasers instead of mirrors? (Score:4, Interesting)
What would be best is a multi-role station. The power generated when "idle" could normally be beamed down to earth via microwave, etc (if that is even possible - I assume the station could not be geostationary because of the extra propulsion required to launch so much mass to that higher orbit).
Another use would be similar to the iss, where there are also modules for astronauts to do science in, as well as them being there to help maintain and assemble the station.
The power generated could also be beamed to long-distance probes that use an electrical ion type drive. Any extra energy they receive from the station simply allows them to accelerate faster. That may be more feasible than beaming the power down to earth.
Re:Spotting may be the problem.. (Score:4, Interesting)
The problem with asteroids are the ones that aren't spotted. The well-known large ones are easy to spot but suddenly a new one shows up and causes trouble.
The earlier you can see them the better - and early enough you may be able to at least do something about it by nudging the trajectory just a fraction to make it miss or hit something harmless. If possible - let it crash into the moon instead. Spectacular - but the risk to humanity is lower.
On the other hand - there are places here on Earth where an impact would solve some problems.
Re:Mirrors (Score:2, Interesting)
Re:People Are Interesting (Score:2, Interesting)
Well, you do realize that the proposals to "go live in space" is not about finding a safer place to live, right? The main reason to find other places to live is because it means that no single event can wipe out the whole species (more colloquially known as not having all eggs in one basket). If thinking that makes me a space nutter, well, I guess I'm okay with that.
Re:Why lasers instead of mirrors? (Score:2, Interesting)
http://www.imdb.com/title/tt0246460/
Anti-asteroid technologies' potential to unite humanity towards a common goal is usually undermined by the depressing reality that almost any technique used to prevent an asteroid strike could be weaponized, or at-least, potentially be used to create a strike deliberately.
http://en.wikipedia.org/wiki/Asteroid_impact_avoidance#Deflection_technology_concerns
It remains to be seen if the baby will get killed in the cradle because of it's distrust for it's neighbors.
Re:"Killer"? Meh. (Score:5, Interesting)
You're absolutely right, from a biological perspective. There have only been a handful of impacts that did any serious damage to the biosphere, but those mostly wiped out everything except for a few "lottery winners" low on the food chain. Humanity, well all mammals really, kind of won the last round when all the dominant animal life was killed off and "rodents" were able to inherit the Earth. However the asteroid that would destroy New York (city or state, your choice) isn't even worth mentioning on those scales, and humanity is occupying an ever larger portion of the surface. Just think of how much the damage would have cost had that Russian meteor blown out the windows in a major metropolitan area, and that one was downright tiny.
Plus, unlike the "war on terror" that has spent ~$1.5 Trillion to little effect beyond deposing some marginally related governments, a system that can deflect dangerous asteroids away from us also has considerable productive use as well: we could deflect valuable asteroids into near-Earth orbit, even capture them into stable Earth or Lunar orbits for processing. That is typically the oft-unspoken goal of most of these sorts of plans, but the big money all comes from the defense department, so that's how they get pitched. Science and economic development projects have to fight over the budgetary crumbs which couldn't feed a project like this. Even the Cold War "Star Wars" missile defense program was designed to double as an asteroid guidance system, or so I've heard.
A futile endeavor (Score:3, Interesting)
They have struck before on a larger scale - with regularity - as documented e.g. by Clube and Napier. Much of their research focused on the long-past break-up of a very large comet and the periodic intersection of Earth's orbit with its remains - which has led to cometary showers, with their impact on societies in more ways than one, also leading among other things to religious developments - ideas of gods and their actions and judgments.
Historically, peoples have looked to their leaders to protect them from catastrophe - and when their leaders fail to do so, i.e. something happens that they simply cannot control, such as a rain of fireballs and meteorites exploding in the atmosphere, then a people will blame its leaders and get rid of them - often violently. This seems to be a basic feature of human psychology, one repeatedly seen in action throughout history.
Knowing this, the leaders have the need to reassure their people that they have things under control - historically, there have e.g. been systems of ritual and sacrifice. Nowadays, reassurances come in a different form: That the sky is watched, that major events only happen "once in a lifetime" (or, earlier, that such things simply couldn't happen - which was long the consensus), coupled with simplistic ideas of weapons and other solutions to take out the threat - solutions that will never be adequate if/when the time comes for real. People are only too happy to play along with such reassurances, to develop them and then to take them and run with them, since the alternative is not too pleasant - recognizing that there is no way to avert such disasters when they arrive.
A very recent book by a historian, "Comets and the Horns of Moses", discusses this whole subject, and much more connected to it. It goes into the history of cometary interaction with our planet - which has long seemed to follow cycles - and both how it has affected life on Earth and how humanity has responded to it - the social, cultural, and political dynamics involved, both in-between and during times of cometary disasters. Looking at the history and the present, it further goes into what seems likely to be coming up. I'd recommend it for the interested.
http://www.amazon.com/Comets-Horns-Moses-Laura-Knight-Jadczyk/dp/1897244835/ref=sr_1_1?ie=UTF8&qid=1360956345&sr=8-1&keywords=comets+and+the+horns+of+moses [amazon.com]
In the present time, one of several clues is the reported sightings collected by the American Meteor Society, which have increased roughly exponentially since 2005 - with 463 events on record for 2005, the increase accelerating year by year with 1628 for 2011 and then 2219 for 2012. Thus far this year - i.e. in one and a half month - there's been 322.