What measures if any will ever be put in place to defend from asteroids?

[Juryoku]

I suppose what I'm asking here is will there ever be preventive measures put in place to present a catastrophic event caused by asteroid impact such as what happened to the dinosaurs? Never mind that, to my knowledge, there isn't even any serious research being done on ways to re-plot the course of an asteroid away from Earth or destroy it, is there?

How long will humanity cross there fingers and hope that such a thing doesn't happen without actually doing anything to prepare for if it does happen?

I guess I should also ask, do any of you think its even worth it to put funding into research for this at this point? Our detection methods for detecting these things aren't necessarily flawless either. Nothing the size of a city is going to sneak by us, but a 50-200ft wide object that could decimate a large part of a city could technically sneak by undetected could it not?

 

Also, could someone explain to me, if there is, what theoretical methods there currently are to preventing a large asteroid impact? Whether it be re-plotting course, or destruction, I'd be very interested. Thanks everyone!

Edited February 21, 2011 by Juryoku

[SMF]

I am aware of two programs involved in identifying and tracking near earth asteroids. The NASA and JPL joint program is called Near-Earth Asteroid Tracking project, and the Planetory Society (co-founded by Carl Sagan) funds small grants to amateur observers. I think that there are several other agencies, world wide, that are involved in finding dangerous asteroids. There are various plans for dealing with a potential threat, but I don't think anything has been funded or even seriously considered. SM

[Spyman]

I suppose what I'm asking here is will there ever be preventive measures put in place to present a catastrophic event caused by asteroid impact such as what happened to the dinosaurs? Never mind that, to my knowledge, there isn't even any serious research being done on ways to re-plot the course of an asteroid away from Earth or destroy it, is there?

It was eventually rolled into S.1281, the NASA Authorization Act of 2005, passed by Congress on December 22, 2005, subsequently signed by the President, and stating in part:

 

The U.S. Congress has declared that the general welfare and security of the United States require that the unique competence of NASA be directed to detecting, tracking, cataloguing, and characterizing near-Earth asteroids and comets in order to provide warning and mitigation of the potential hazard of such near-Earth objects to the Earth. The NASA Administrator shall plan, develop, and implement a Near-Earth Object Survey program to detect, track, catalogue, and characterize the physical characteristics of near- Earth objects equal to or greater than 140 meters in diameter in order to assess the threat of such near-Earth objects to the Earth. It shall be the goal of the Survey program to achieve 90% completion of its near-Earth object catalogue (based on statistically predicted populations of near-Earth objects) within 15 years after the date of enactment of this Act. The NASA Administrator shall transmit to Congress not later than 1 year after the date of enactment of this Act an initial report that provides the following: (A) An analysis of possible alternatives that NASA may employ to carry out the Survey program, including ground-based and space-based alternatives with technical descriptions. (B) A recommended option and proposed budget to carry out the Survey program pursuant to the recommended option. © Analysis of possible alternatives that NASA could employ to divert an object on a likely collision course with Earth. The result of this directive was a report presented to Congress in early March 2007. This was an Analysis of Alternatives (AoA) study led by NASA's Program Analysis and Evaluation (PA&E) office with support from outside consultants, the Aerospace Corporation, NASA Langley Research Center (LaRC), and SAIC (amongst others).

http://en.wikipedia.org/wiki/Asteroid_impact_avoidance

 

 

Also, could someone explain to me, if there is, what theoretical methods there currently are to preventing a large asteroid impact? Whether it be re-plotting course, or destruction, I'd be very interested. Thanks everyone!

Collision avoidance strategies

Various collision avoidance techniques have different trade-offs with respect to metrics such as overall performance, cost, operations, and technology readiness. There are various methods for changing the course of an asteroid/comet. These can be differentiated by various types of attributes such as the type of mitigation (deflection or fragmentation), energy source (kinetic, electromagnetic, gravitational, solar/thermal, or nuclear), and approach strategy (interception, rendezvous, or remote station). Strategies fall into two basic sets: destruction and delay.

 

Destruction concentrates on rendering the impactor harmless by fragmenting it and scattering the fragments so that they miss the Earth or burn up in the atmosphere. This does not always solve the problem, as sufficient amounts of material hitting the Earth at high speed can be devastating even if they are not collected together in a single body. The amount of energy released by a single large collision or many small collisions is essentially the same, given the physics of kinetic and potential energy. If a large amount of energy is transmitted, it could heat the surface of the planet to an uninhabitable temperature.

 

Collision avoidance strategies can also be seen as either direct, or indirect. The direct methods, such as nuclear bombs or kinetic impactors, violently intercept the bolide's path. Direct methods are preferred because they are generally less costly in time and money. Their effects may be immediate, thus saving precious time. These methods might work for short-notice, or even long-notice threats, from solid objects that can be directly pushed, but probably not effective against loosely aggregated rubble piles. The indirect methods, such as gravity tractors, attaching rockets or mass drivers, laser canons, etc., will travel to the object then take more time to change course up to 180 degrees to fly along side, and then will also take much more time to change the asteroids path just enough so it will miss Earth.

http://en.wikipedia.org/wiki/Asteroid_impact_avoidance#Collision_avoidance_strategies

(Follow the Link for a more detailed list of methods.)

[JohnB]

In 2008 the Russian Academy of Sciences sponsored a large gathering to commemorate the 100th Anniversary of the Tunguska Event. Papers were presented on a range of topics from being about the actual event to the likelihood of another and mitigation strategies.

 

Unfortunately the papers were presented in Russian, but the complete list and the Abstracts in Russian and English can be found here.

http://tunguska.sai.msu.ru/content/abstract_all.pdf

 

Many are rather detailed for abstracts and the whole do present an interesting and informative read as to the state of the science as of 2008. The Russians seem to be taking the threat more seriously than in the West given the content of the papers and the hosting by the RAS of the website for the Holocene Impact Working Group. The ideas put forward by the HIWG are quite scary.

[imatfaal]

I think we are still relying on Bruce Willis

[Mrs Zeta]

For some comprehensive discussion of the diferent issues see here:

 

http://lifeboat.com/ex/asteroid.shield