Last month the Chinese spacecraft Chang’e-2 (named after the Chinese moon goddess) had a very close encounter with asteroid Toutatis and was able to snap a few beautiful pictures. So what, you might say. It’s a space rock. What gives?
True, many asteroids fall into the “seen one, seen them all” category – Toutatis is pretty much one of those. An elongated potato-shaped rock about 3 miles long, slowly tumbling along its main axis – lots of asteroids we’ve got pictures of are like that. But what’s special about this encounter ?
First off, Chang’e-2’s primary mission was to explore and map the Moon. It did its duty, faithfully zipping around Earth’s companion, and once it was done the engineers sent it to a Lagrange point, a gravity-stable point in space where Earth’s and the Sun’s gravity are in exact balance. After hanging out there for some time, the engineers got the car-sized craft moving again so it was poised for a close up view of Toutatis as it zipped by.
We usually think of asteroids as slow-moving tumbling rocks in space – we’ve certainly seen plenty of them in every space-based science fiction show, along with plenty of popular science television features. The reality is quite different. Asteroids – like most space object, hurtle along at crazy speeds — for Toutatis that’s about 7 miles per second. That’s fast! And if you, the observer, also move (most likely also at a speed that would make the average speed trap go up in a sad puff of smoke), the asteroid appears to move even faster. For Chang’e-2, it meant that Toutatis was screaming by at a blistering 24,000 miles per hour.
Try to take a pictures of something that’s going that fast! And Toutatis was a paltry 2 miles away when it crossed Chang’e-2’s path. So you see, there’s some awesome engineering and science and technology involved to even get one single snapshot.
Of course, Chang’e-2 was not the only one to take a gander at Toutatis – NASA also obtained some useful radar images, which incidentally revealed the slow tumble of the rock), but nothing really beats a good old-fashioned photograph when it comes to the ooh and aah factor.
Looks like Toutatis is mostly smooth with a few boulders it has managed to gather along its path – not exactly something you’d want to put on your list of future vacation spots, but it’s an awesome sight either way.
Near Earth asteroids have become quite the focus of attention lately, since they actually have the true potential to wipe out life on Earth as we know it, if one of them should actually smash into our fair planet. Luckily, there are a few vigilant eyes trained upon those rocks, calculating their orbits and hopefully warning us in time of possible collisions.
Our pal Toutatis poses no threat to us. And with that — have a Happy New Year!
Learn more about Toutatis at http://www.nasa.gov/vision/universe/watchtheskies/toutatis-092804.html
Beate Czogalla is the Professor of Theater Design in the Department of Theatre and Dance at Georgia College & State University. She has had a lifelong interest in space exploration and has been a Solar System Ambassador for the Jet Propulsion Laboratory/ NASA for many years. She can be reached at firstname.lastname@example.org