I was presenting this week’s Astrolunch talk at university. I chose to discuss space debris, and this included a quick overview of the Chinese missile test last year, which create a huge cloud of fragmented debris, much of which is still orbiting the Earth. In January 2007, China launched a surface-to-orbit missile that destroyed a satellite named Fengyun 1C. The act was internationally condemned, though of course no one really punished them.
You can see the debris in this screenshot. Each little Chinese flag is a piece of the satellite that remains in orbit.
If you want to track this debris yourself, you can do so in Google Earth using this handy KMZ file that I’ve created. It uses the same code as my previous efforts for tracking the ISS on Google Earth and tracking satellites on Google Earth in general.
Also, if you’re interested in the talk I gave, you can download the PDF of ‘Space Debris‘.
I wonder if this post will be visible through the Great Firewall of China?
UPDATE: The data used for this Google Earth feed comes directly from NORAD, who provide tracking data for most satellites and other orbiting bodies. I should stress that this only shows the trackable debris. This is only a percentage of what is up there. Some objects are too small to be tracked by radar and so do not appear.
April 21st, 2008 at 1:46 pm
Oh geez, Rob, this is awful! I had no idea that space debris would scatter around the Earth so significantly! What’s going to happen to the satellite that the US just blew up with a missile; will it do the same exact thing? Also, how big/small are these pieces of debris? Are we talking centimeter sizes, or are we talking a few kilos each?
Ethan
April 21st, 2008 at 1:55 pm
The debris ranges in sizes from a few mm to a few cm. USA-193, the spy satellite that they shot down in February, has much less debris and much of that is expected to fall toward the Earth sooner or later. The problem with Fengyun 1C is that it was in a high orbit when it was destroyed.
April 21st, 2008 at 2:25 pm
there is lots of junk of all kinds orbiting the earth:
http://toomanytribbles.blogspot.com/2008/04/junk-in-space.html
and regarding the GFoC, wonder no more. i’m in beijing.
April 22nd, 2008 at 9:45 am
First off, where did you get the debris location data from? As no source of data is cited, I assume that you created a simulation of satellite explosion in space. If it is a simulation or merely rough calculations, I seriously doubt the model is close to correct. The Chinese hadn’t publicize the projectile of the missile, its speed, its energy and where the missile hits the satellite and many other details needed to accurately predict where the debris will go to. Of course, there must be debris orbiting Earth right now, but not like that shown in your model.
US ground radar can detect a piece of space debris as small as 10cm across. But most of the satellite debris are smaller than 10cm. This suggests that you didn’t use a reliable data for the model. So this is nothing more than a fun project illustrating what you think the debris should be, rather than where the debris are actually be.
April 22nd, 2008 at 9:53 am
Neo: The data comes from NORAD (http://celestrak.com/NORAD/elements/). They make quite a lot of trackable data available. The debris size varies quite a lot, ranging from 1mm to several tens of centimetres and they use radar to track the objects as their orbits change over time. The NORAD data is updated sometimes more than once a day.
So no, it is not a simulation. This model is scientifically valid and is in fact the same model that is used to predict visible passes of the International Space Station, which have always been very accurate for me.
You’re right in that I have should have noted the data source. I will edit the post to show this.
May 10th, 2008 at 2:58 pm
Here is the NASA Orbital Debris Quarterly. http://orbitaldebris.jsc.nasa.gov/newsletter/pdfs/ODQNv12i2.pdf