I usually plan more carefully for these events and plot the position and expected trail of the asteroid using The Sky 6 Professional. However, this one almost caught me out as I hadn’t really planned for this session specifically. I had a general plan to image some small galaxies, but a tree was in the way of my 1st target so whilst waiting, I jumped on the web to have a look at the asteroid action on SpaceWeather and lo and behold, 2008 TT26 was due to make its fly by that very evening! The SpaceWeather website is a great resource for these NEO’s.
Modifying my plans for the evening, I used The Sky 6 Pro to download the orbital elements, crossed my fingers and did a “Find” object and it showed that TT26 would indeed be above the horizon later in the evening – often these objects are below the horizon so it was nice to find this one getting up to around 40 degrees altitude around midnight.
As the hour approached, I had CCDSoft (camera control software) and The Sky 6 Professional running on the Notebook, with The Sky 6 zoomed in to show the field of view of my CCD chip. I kept hitting the “Time” update button as TT26 approached the FOV indicator whilst manually flicking to the live image in CCDSoft to compare the field stars. It was quite amazing (and reassuring!) to see the live TT26 pop into the CCD frame at the place and time as displayed by The Sky 6 simulation! These tools are simply fantastic.
What I hadn’t really expected was the pace of this fella, so I had to grab some quick images to establish the optimum exposure, then leap frog ahead of the rock to begin capturing the trail. A couple of test exposures of 2 and 5 minutes recorded a much fainter tail, as the skies are quite light polluted in that direction (grrr!) so the sky background began to swamp the faint, extended trail. The optimum exposure seemed to be 1 minute so I grabbed 40 frames and of these, TT26 was in 15 of them.
The extra frames were grabbed so I could stack the images to get a smoother background for the animation, to mitigate some of the effects of the horrid light pollution and noise from such short exposures. Whilst my wife is very supportive of my hobby, she still has a somewhat bemused look on her face when I tell her of my latest cosmic exploits!
Cheers
Dennis