September 27th, 2005
Don Quijote and the asteroids
No, this is not the title of a sequel to what is probably the first novel in history. In this case, Don Quijote is the name of a space mission that will be launched in 2007 or later by the European Space Agency (ESA). The goal of this mission is to check if it’s possible to modify the trajectory of an asteroid before it becomes a threat to Earth. The Don Quijote mission will use two spacecrafts, Sancho, which will observe one asteroid, while the second, Hidalgo, will hit it at a very high relative speed. The ESA has selected two asteroids as targets and will decide about the space technology used for this future mission in 2006. This sure looks like science fiction. But can it be dangerous if the targeted asteroid moves in a ‘wrong’ direction? The ESA and other experts worldwide says no.
Let’s first look at the facts as described in the ESA news release.
Based on the recommendations of asteroid experts, ESA has selected two target asteroids for its Near-Earth Object deflecting mission, Don Quijote.
Don Quijote is an asteroid-deflecting mission currently under study by ESA’s Advanced Concepts Team (ACT).
So ESA has selected the targets and is about to choose the technology next year. But it already knows the schedule of this future mission.
The current scenario envisages two spacecraft in separate interplanetary trajectories. One spacecraft (Hidalgo) will impact an asteroid, the other (Sancho) will arrive earlier at the target asteroid, rendezvous and orbit the asteroid for several months, observing it before and after the impact to detect any changes in its orbit.
Below is an artist’s rendition of Hidalgo before ‘attacking’ its target, while Sancho, not visible here, will observe the impact without taking unnecessary risk (Credit: ESA/Deimos Space). You’ll find other images about the Don Quijote mission on this page.
Can such a mission be successful and help to deflect in the future an asteroid which would have the poor taste to land on Earth with the catastrophic effects you can imagine?
Most world experts agree that this capability [to deflect an asteroid] is now within our reach. A mission like ESA’s Don Quijote could provide a means to assess a threatening NEO [Near Earth Object], and take concrete steps to deflect it away from the Earth.
But every good performance needs rehearsing and in order to be ready for such a threat, we should try our hardware on a harmless asteroid first. Don Quijote would be the first mission to make such an attempt.
This is fine, but what if things go wrong?
Experts world-wide say the answer is no. Even a very dramatic impact of a heavy spacecraft on a small asteroid would only result in a minuscule modification of the object’s orbit. In fact the change would be so small that the Don Quijote mission requires two spacecrafts — one to monitor the impact of the other. The second spacecraft measures the subtle variation of the object’s orbital parameters that would not be noticeable from Earth.
Do you feel safe after reading this statement? Whether your answer is yes or no, here is a link to additional information about the Don Quijote Mission.
Finally, on an unrelated subject, but because I really enjoyed what some nanotechnolàgists did, read this story from April 2005, "The World’s Fastest Nano-Optical Shutter," to discover a nanoscale image of Don Quixote and Sancho Panza created in vanadium dioxide…
Sources: European Space Agency news release, September 26, 2005; and various web sites
You’ll find related stories by following the links below.
