|Animation of 7 individual frames taken with the Arecibo radar telescope on Puerto Rico. Credits: NAIC-Arecibo/NSF|
Individual images with which the above animation was created. Credits: NAIC-Arecibo/NSF
Goodbye, 'Halloween Asteroid'
This is 'Halloween Asteroid' 2015 TB145, as it was approaching Earth, imaged with the Arecibo telescope radar. As it turned out, the space rock measures around 600 meters and rotates once every five hours around its axis. It is thus larger than initially thought.
For optical telescopes, 2015 TB145 remained a tiny speck of light even at closest approach, which, when writing these lines, has already occurred. We are still alive. But the sudden appearance of this asteroid (which might be a dormant comet) should be a reminder that we should to to more to detect Near Earth Objects which might pose a potential threat to our planet.