Stargrazing: In search of superstars

Supergiant: An artists impression of what a massive Red Supergiant would look like. Credit:  ESO/L. Calçada
Supergiant: An artists impression of what a massive Red Supergiant would look like. Credit: ESO/L. Calçada

Space, the final frontier. There is still very little that we actually understand about the vast Universe we live in. Still, the human race is determined to go out and explore the cosmos, so just to make sure we know exactly what we're getting into, here are a couple of discoveries that will amaze you.

Ok, stars are weird! No, let me rephrase that – some stars are weird. But some stars out there in the Universe are downright odd! Let’s have a look at a few and you’ll see what I mean.

We’ve just discovered one of the biggest stars imaginable, and it’s basically in our own backyard. It’s about 15,000 light years away. It’s called a ‘Red Supergiant’ and is so huge that if we were to place it in the centre of our Solar System, in place of our own Sun, it would cover all four rocky planets and extend beyond the orbit of Jupiter.

This stellar monster is in the top five of the biggest stars we’ve ever found. Now, I’m not saying aliens are involved but there’s something odd going on.  Astronomers started observing one of the most enigmatic stars known to humanity. Only 1,400 light years away, it’s simply known as Tabby’s Star.

The alert went out last month that the odd dips in the brightness of the star, observed a few times before, were happening once again. These dips have yet to be explained, giving rise to all sorts of theories, including far out ideas like a huge megastructure built by an advanced alien civilization passing in front of it. Yep, I’m thinking Luke and the Death Star here too!

What makes this star so bizarre is that its dips in brightness don’t seem to follow any obvious patterns. Something seems to pass in front of the star. It’s also getting noticeably less bright over time, as if someone is turning down its energy output.

While the odds that whatever is getting in between the star and our telescopes is artificial are still very low, that possibility still can't be ruled out.

Finally, you can’t see them now, but in five year’s time, two enormous distant stars will collide, brightening by a factor of 10,000 and instantly becoming one of the brightest things in the sky in 2022, even in daylight!

The stars are 1,800 light years away from us which means the explosion has already happened - 1800 years ago! It’ll certainly be mesmerizing for us to watch, but for astronomers, it could provide major insight into how stars develop over time.​