Sandia simulation shows small near-earth objects can cause big troubles

William Atkins
Saturday, 22 December 2007 21:02

Science - Space

What could cause great concern and worry to scientists and all humankind is that smaller space bodies (smaller than 100 feet across), like asteroids and comets, impact the Earth once every few hundreds of years. On the other hand, larger asteroids and comets (larger than 100 feet in diameter) only impact the Earth once every few thousands of years. Thus, we have a much greater chance of a close encounter with the smaller space bodies than the bigger ones.

For more information about the Sandia researchers results, please go to the Sandia press release, from December 17, 2007. It is found at: http://www.sandia.gov/news/resources/releases/2007/asteroid.html.

Boslough and co-author and fellow Sandia researcher Dave Crawford will have their results entitled “Low-altitude airbursts and the impact threat” written up in a future issue of the International Journal of Impact Engineering. They initially presented the highlights of their paper at the December 11, 2007 meeting of the American Geophysical Union in San Francisco, California.

This new information makes it even more important for astronomers around the world to expand and improve their tracking of near-earth space bodies that have the potential of impacting the Earth. The Near-Earth Object Program, directed by NASA's Jet Propulsion Laboratory, is one such program dedicated to tracking near-earth objects (NEOs), which include comets and asteroids whose orbits have been modified by the gravitational attraction of nearby planets into orbits that allow them to enter the Earth's neighborhood.

The study of NEOs has been systematically studied by scientists for over forty years. They have learned that asteroids and comets have been colliding with the Earth throughout its 4.5 billion year history. These scientists have concluded that the impact of these Near-Earth Objects with our Earth could have catastrophic consequences to our home planet. They represent a definite and serious natural hazard to our health and safety.

NASA maintains a Web page of the most significant NEO threats in the next 100 years for Earth. It can be found at: http://neo.jpl.nasa.gov/risk/.

Over four thousand NEOs have been discovered and are now under continuous tracking here on Earth and out in space.

The United Kingdom also study NEOs through its NEO Information Center: http://www.nearearthobjects.co.uk/.

[Author's comment: "Scandia" changed to "Sandia" per reader's request.]