Wednesday, December 12, 2012

Asteroid 4179 Toutatis

Tonight was a first for the Lost Pleiad Observatory staff (that's me...sole proprietor, operator, custodian and resident trouble maker).  Asteroid 4179 Toutatis is in the process of making a close pass to Earth, and while I have observed asteroids previously, tonight I decided to take a series of pictures of the asteroid and then stitch them together to make an animation.

Before I provide the goods, it is worth knowing that asteroid Toutatis will only come within 4.3 million miles of Earth on this pass.  The images at left are computer-generated views of Toutatis, constructed using radar observations from NASA's Goldstone Observatory.

Toutatis is about 3 miles wide and makes one trip around the sun every four years.  Toutatis is a potentially hazardous asteroid, meaning that it could pose a threat to our planet at some point in the far future. The current flyby is no cause for concern, however, and I suppose that if you are reading this you know this to be true!  You made it through the night! At its closest approach, which was at approximately 11:40 PM MST Tuesday night, Toutatis was about 18 times farther away from Earth than the moon is.

Using my TEC 140 APO, along with my Canon T2i and the software program BackyardEos, I ended up with 49 usable exposures of the asteroid (don't ask about the others...even the dog managed to mess a few up!).  Each exposure was for 30 seconds and I have stitched them into the looping GIF below at 10 frames per second using Photoshop CS6.  I did no processing of the images, other than to reduce the size of each exposure so that the GIF was not a bazillion megabytes.  As it ended up the animation is a 12.8 MB GIF, so do allow it time to load.  The animation runs from approximately 8:59 to 9:48 PM local time, or 0359 - 0448 UT 12/12/12.  (Or, as folks in the UK would note the date, 12/12/12.)  Finally, you may notice that the background sky is brighter in the later frames...this is due to the asteroid appearing to move in the direction of the Tucson light dome.  Without further ado...the GIF!
Click to enlarge (and remember to give it time to load!)


  1. This is some really good stuff. Any idea what galaxy that is up a bit and to the left?

    1. Thanks Michael- No idea what galaxy, although I am sure that it could be easily figured out using the asteroid ephemerides from Tuesday night. Considering I was shooting into the Tucson light dome and the exposure was only 30 seconds, I suspect it is a large and bright galaxy.

    2. Nevermind, NGC 718 is too far away. I'm looking in Stellarium but I don't see anything in that position.

    3. Rumor has it that it may be NGC 493...

  2. Well done Alan - what a cool video!