An asteroid with an orbit that brings it very close to the Earth this week, with it's closest approach on 15 February at 20:00 UT. For the past couple of weeks staff astronomer, Tim Lister and I have been trying to image this asteroid, called 2012 DA14. We have tried observing from our site at Cerro Tololo which is still undergoing astronomical commissioning, but the asteroid was very faint, appeared very low on the horizon, very close to twilight in a part of the sky which made it difficult for our 1-meter telescopes to observe. All of that meant that we had not had much luck getting images.
Fortunately over the past couple of days we have been able to observe it using our 2-meter telescope at Siding Spring, Faulkes Telescope South. We would have used this sooner but the severe bush fires that ravaged New South Wales had delayed those observations.
On 14th February we managed to get some images of the asteroid before it went below the horizon, but today we have been able to get many more measurements. At time of writing Tim Lister is using our FLOYDS spectrograph to analyse the surface and composition of the asteroid.
I created the animation above from Tim's reference images. These images were taken between 09:53 and 11:28 on 15 February, and give a clear picture of how fast the asteroid is travelling.
The elongated shape is because the asteroid is very slightly trailed in the images, even though the exposure times were low (~5s in Solar filter). There appears to be change in the asteroid's shape which may indicate it is rotating and non-spherical.
(Animation was made with Adobe Photoshop, painstakingly aligning each frame on the the asteroid and attempting to balance the contrast and brightness. It was then exported to an animated GIF. There are 5 frames were the telescope tracks the asteroid not the sky, where the asteroid looks round and everything else is trailed. I included those to see what a difference it makes to our perception of the flight of 2012 DA14.)
