This site uses cookies. By continuing to use this site you agree to our use of cookies. To find out more, see our Privacy and Cookies policy.
Skip to the content

Share this

Free weekly newswire

Sign up to receive all our latest news direct to your inbox.

Physics on film

100 Second Science Your scientific questions answered simply by specialists in less than 100 seconds.

Watch now

Bright Recruits

At all stages of your career – whether you're an undergraduate, graduate, researcher or industry professional – can help find the job for you.

Find your perfect job

Physics connect

Are you looking for a supplier? Physics Connect lists thousands of scientific companies, businesses, non-profit organizations, institutions and experts worldwide.

Start your search today


Avoiding asteroid Armageddon

Impact zone That’s a lot of dots

By Michael Banks in Miami, Florida

We all know the plot for the film Armageddon starring Bruce Willis. An asteroid the size of Texas is on a collision course with Earth, and the US government sends a bunch of astronauts to plant a nuclear device underneath the asteroid to blow it to pieces, thus saving humanity.

Well that is how it goes in Hollywood. But what would we do if we suddenly found a large asteroid that would hit the Earth within the next 50 years?

Last night David Dearborn, a physicist at Lawrence Livermore National Laboratory in California, gave a talk here at the 216th American Astronomical Society meeting in Miami, Florida, about the best technologies to avoid an asteroid extinction event.

In 1998 NASA started a project named Spaceguard with the aim of cataloguing 90% of all asteroids in the solar system larger than a kilometre before 1998. Currently the project has detected around 80%, mainly because, rather unsettlingly, astronomers are finding more and more of them.

Then, in 2005, Congress asked astronomers to catalogue 90% of asteroids greater than 140 m by 2020 using a number of telescopes including the Large Synoptic Survey Telescope, which is currently being built in Chile and is expected to come online in 2015.

If an asteroid is on a collision course, Dearborn says that it is important to know its composition, whether it is made up of rubble, has a solid core, or even if it is a collection of solid rocks held together by rubble.

One point Dearborn reiterated is to deflect an asteroid only when we are 100% confident that it will hit the Earth. “You have to leave it alone until you know if it is going to be a problem,” says Dearborn.

So how do you blow up an asteroid or at the very least deflect it out of harms way? One option is painting the asteroid white, which would change its albedo and slowly start to change its orbit. Given that Dearborn says it would take decades to carry out this paintball exercise on a celestial scale it is perhaps not the best option.

Another is firing a high-powered laser pulse at the asteroid, but this again would take around 6000 years to change its speed by around 1 metre per second. “The National Ignition Facility is not really designed for shooting asteroids,” says Dearborn.

So the best technique for deflecting them is via a nuclear explosion. Two options are to activate a nuclear device just before impact or attempting to strike the object with a nuclear weapon. Dearborn presented a variety of models showing how an impact would break up an asteroid depending on its composition. “Current nuclear technology could handle most possible threats,” concludes Dearborn.

I guess Bruce Willis had it right all along.

This entry was posted in AAS May Meeting 2010. Bookmark the permalink.
View all posts by this author  | View this author's profile

One comment to Avoiding asteroid Armageddon

  1. Mind Deep

    Destroying economic developments worldwide are making surviving technologies untenable if not justified for corporate-military
    profits of Earth ownwers. If we can calculate that a NEO is not only ‘100% confident that it will hit the Earth’ but will it
    hit hunger dominated lands (opposed to our money elite territory) then we will undercover refine the natural collision propagandizanding the opposite that we are high tech defending enemy lands in the range of impact.


  • Comments should be relevant to the article and not be used to promote your own work, products or services.
  • Please keep your comments brief (we recommend a maximum of 250 words).
  • We reserve the right to remove excessively long, inappropriate or offensive entries.

Show/hide formatting guidelines

Tag Description Example Output
<a> Hyperlink <a href="">google</a> google
<abbr> Abbreviation <abbr title="World Health Organisation" >WHO</abbr> WHO
<acronym> Acronym <acronym title="as soon as possible">ASAP</acronym> ASAP
<b> Bold <b>Some text</b> Some text
<blockquote> Quoted from another source <blockquote cite="">IOP</blockquote>
<cite> Cite <cite>Diagram 1</cite> Diagram 1
<del> Deleted text From this line<del datetime="2012-12-17"> this text was deleted</del> From this line this text was deleted
<em> Emphasized text In this line<em> this text was emphasised</em> In this line this text was emphasised
<i> Italic <i>Some text</i> Some text
<q> Quotation WWF goal is to build a future <q cite="">
where people live in harmony with nature and animals</q>
WWF goal is to build a future
where people live in harmony with nature and animals
<strike> Strike text <strike>Some text</strike> Some text
<strong> Stronger emphasis of text <strong>Some text</strong> Some text