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On the night of March 31st 2007, an NEO (Nearth Earth Object) in the shape of asteroid 2006 VV2 passed just 3.5 million kms from earth. This asteroid was imaged from Raheny Observatory, Dublin. See the movie and the imagery here.
Asteroid 2006 VV2 2006 VV2 was discovered by LINEAR (MIT) on November 11, 2006. It approached Earth within 0.023 AU (8.8 lunar distances, 3.4 million km) on March 31. Its physical properties are unknown, but its absolute magnitude of 16.7 suggests a diameter within a factor of two of 1.5 km. If past experience is a guide, then there is a ~1/6 chance that it is a binary system. The above animation is taken from 70 indiviual frames of 15seconds each taken 30 seconds apart. The imaging scope was a Celestron 80EDII "Onyx " Refractor. Unguided frames on a CGE mount. This really shows just how fast this object was moving. The object moved 34' 15" over the course of this session which began at 22:39:34UTC and ended at 23:15:56UTC. This gave a total image time of 36minutes 22 seconds. Given that the asteroid was just over 3.5million kms distant at the time and given the anglular motion over that period, I calculate that the object moved a distand of 34,868kms over the course of this movie and was travelling at an incredible 57,529kph. Somebody give that rock a speeding ticket!
This is the closest approach predicted for an object this intrinsically bright until May 2036, when (66391) 1999 KW4 will approach within 6.0 lunar distances. Image By Dave grennan, 70 x 15seconds, Celestron 80ED "Onyx" refractor, ATIK16HR CCD. David Moore - Astronomy Ireland sent me this observation. An Amazing night of astronomy!!! March 31st/April 1st (this is NO April Fool joke!!!) Looking at Dave Grennan's excellent maps on www.astronomy.ie I noticed 2006 VV2 would pass very close to a 7th magnitude star (SAO 99198, mag. 7.6) making it exceptionally easy to locate. Just find the star and wait for the asteroid to pass. I alerted dozens of colleagues and rushed out to observe this (we had already alerted 7,000 people to our special web page on our website www.astronomy.ie ). Calculations showed closest approach was at 9:38pm BST March 31 when VV2 would be just 13 arc seconds away from the star and moving at 1 arc second per second! I drove to a dark sky site north of Dublin city near Ashbourne and quickly set up an 8-inch Celestron SCT. Hazy skies and a Full Moon just 15 degrees from the target star made it hard to locate. But eventually I located it at 9:43pm BST just 5 minutes after closest approach. The bright star had 2 dimmer stars either side of it. A few seconds later it was obvious that the 'star' below the brightest star (SAO 99198) had moved! I had just seen 2006 VV2!!! The other star (dimmer than SAO 99198) was later identified as magnitude 9.6 and the asteroid was the same brightness, so the prediction of 10.0 was quite close, with the asteroid actually being a little brighter than predicted if anything. Unfortunately by this time the asteroid was now 5 arc minutes from the star and so seeing it 'move' in real time was not possible. A few clouds drifted over the target during the following hours, but at 1:19am BST April 1 the asteroid passed by a faint star and I could clearly 'see' it moving! This is only the second time I have seen real time motion in an asteroid passing close to Earth. In total I watched the asteroid drift through star fields for 4 hours, an experience I will never forget. Seamus Bonner, Astronomy Ireland Membership Secretary joined me for most of the session Regards and clear skies,
David Moore. |
