Looking Up: What's In A Name? That Which We Call Sargas...

Jul 31, 2017

The mighty Scorpion rises!
Credit M. Procell

This week on Looking Up Hal tells the strange tale of a star located in the tail of the scorpion.

Have you ever had that “dead inside” feeling? Not too peppy? If so, you may have something in common with the very interesting star, Sargas. Also known as Theta Scorpii, Sargas is the third brightest star in the constellation Scorpius. It is the southern-most star in the constellation, forming the bottom of the scorpion’s tail, just before it curls back up to the north. 

Sargas means, well, we don’t know. The name is thought to be Sumerian, but no-one really knows what it means. And that’s too bad, because at 20 times the size of our Sun, and spinning at 50 times faster, Sargas is a very freaky place. At its core is dead helium – in that the star has run out of hydrogen to fuse into helium, and only the fused helium core remains. As it marches down the star evolutionary chart, Sargas will swell up to become a red giant, at least five times bigger than it is now. When it does that, the helium at the core will start to fuse into carbon and oxygen, and Sargas will become a huge White Dwarf star. So, keep an eye on Sargas, it’s about to have a serious waistline problem.

If you’d like to take a closer look at Sargas 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.

Keep looking up...