Looking Up: The Comet Who Came In From The Cold

Nov 6, 2017

Credit gnokii / Creative Commons Open Clipart

This week on Looking Up we hear the strange tale of a comet with a killer name - ASSASN 1.

Every now and then, we are graced by a visit from a comet from deep space, and right now, we have one of those visitors in the inner-solar system right now.

The comet has a strange name – ASSASN1. It’s not a killer comet though, but rather it was discovered by the All Sky Automated Survey for Supernovae system, hence the name. It’s also called the less poetic Comet C/2017 01.

It will take a telescope to see it, and you may need to Google it for a good star map, but it’s worth a look. Astronomers think this is the first time this particular hunk of rock and ice has fallen in toward the Sun, after perhaps 4 billion years or more way out beyond the planets. It also startled astronomers when it increased in brightness a hundred fold, likely from ice and dust being blown off its surface and illuminated by the Sun.

If you find it, you’ll see the comet as a green ball of light, due to the presence of diatomic carbon, glowing in the Sun’s ultraviolet light. It’s in our Colorado sky right now, heading toward the North Star Polaris. It’s just past its closest approach to the Sun, and is now starting its long journey way back to where it came from. Be sure to wave goodbye, as you likely won’t be around to see it when it next visits the Sun in a bit over 9000 years.

If you’d like to take a closer look at the comet or any of the wonderful and amazing things in the sky, please visit csastro.org for a link to information on our monthly meetings and our free public star parties.