Astroblog: Near Earth Object 2012 TC4 Flys by (12 October 2017)

Friday, October 13, 2017

Near Earth Object 2012 TC4 Flys by (12 October 2017)


Asteroid 2012 TC4 imaged with iTelescope T20 on 11 October 2017. MAX stack of 8 x 60 second luminance images, stacked in ImageJ. Over enhanced to show the asteroid. Click to embiggen.	Animation of all 8 frames, made with ImageJ. CLick to embiggen.

Five years ago to the day, NEO 2012 TC4 passed 0.2 Earth Moon distances away from us. This time the asteroid was even closer, at 0.13 Earth Moon distances (a mere 50,150 km) and hurtling though the sky at a blistering 13 arc minutes a second. At this speed the iTelescopes cannot track the asteroid. Even with a 60 second exposure the asteroid is a mere streak 45 minutes before closest approach.

I managed to capture it by camping out where the Minor Planet Ephemeris center predicted it would be and waiting until the time it would be predicted to pass across the field of view before imaging.

The asteroid zipped across the field in a mere 12 minutes. The asteroid is a fast rotator, with a period of 12 minutes and 14 seconds, and the asteroid can be seen to dim midfield.

There are quite a few good images of the asteroid on the web, like this one from the SONEAR observatory.

Labels: 2012 TC4, iTelescope, NEO