Interplanetary securityScientists seek ways to ward off killer asteroids

Published 22 December 2008

The U.S. Congress has tasked a blue-ribbon panel of scientists with two missions: Find better ways to detect and deflect asteroids that might hit Earth; more than 5,000 near Earth objects, including 789 potentially hazardous objects, have been identified so far

Have you made plans yet for Easter Sunday, 13 April 2036? If not, you may want to wait a little bit before you firm up your plans. Here is why: We have written several stories about interplanetary security, guided by the insight that if Earth is hit by a large asteroid, the consequences would render many, if not most, of the homeland security measures we take moot. Others share this view. A blue-ribbon panel of scientists is trying to determine the best way to detect and ward off any wandering space rocks that might be on a collision course with Earth. “We’re looking for the killer asteroid,” James Heasley, of the University of Hawaii’s Institute for Astronomy, recently told the committee that the National Academy of Sciences created at Congress’s request. Congress asked the academy to conduct the study after astronomers were unable to eliminate an extremely slight chance that an asteroid called Apophis will slam into Earth with devastating effect in 2036 (see 25 September 2008 HS Daily Wire).

McClatchy’s Robert Boyd writes that Apophis was discovered in 2004 about 17 million miles from Earth on a course that would overlap our planet’s orbit in 2029 and return seven years later. Observers said that the asteroid — a massive boulder left over from the birth of the solar system — is about 1,000 feet wide and weighs at least 50 million tons. After further observations, astronomers reported that the asteroid would skim by Earth harmlessly in 2029, but it has a one in 44,000 probability of slamming into our planet on Easter Sunday, 13 April 2036.

Small changes in Apophis’ path that could make the difference between a hit or a miss are possible, according to Jon Giorgini, a planetary analyst in NASA’s Jet Propulsion Laboratory in Pasadena, California. “We have not eliminated the threat in 2036,” Lindley Johnson, the manager of NASA’s asteroid detection program, told the committee.

The academy panel is headed by Irwin Shapiro, a former director of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts. Boyd writes that it has a two-part assignment from Congress: Detect and deflect asteroids that might hit Earth.

First, the Shapiro committee is supposed to propose the best way to detect and analyze 90 percent of the so-called “near Earth objects” (NEOs) orbiting between Mars and Venus that are wider than 460 feet by 2020. About 20 percent of these are identified as potentially hazardous objects because