Alpha Centauri: Two bright princesses and a red dwarf

Dan Wild

I remember as a teenager, blinking though binoculars, excited that I could just make out Alpha Centauri as a double star. Then I borrowed a low-end refractor telescope and could more easily make out the binary nature of the pair. It was the Jesuit, Father Jean Richaud (1633-1693), who first determined the binary using his …

Epsilon Eridani: Already in the sights of asteroid miners

Dan Wild

Although known to early star gazers, Epsilon Eridani does not figure heavily in myth. Claudius Ptolemy was the first astronomer to pay this star any sustained attention, cataloguing it in his famous 2nd-century Almagest. Indeed, it was Ptolemy that named the constellation Eridanus, after the ancient Greek word for ‘river’ (Ποταμού). Epsilon Eridani famously entered …

Teegarden’s Star: A nearby red dwarf with two rocky planets

Dan Wild

While Teegarden’s Star is rarely talked about at dinner parties, it’s only a matter of time. Why? Two words. Habitable planets. At only 0.09 solar masses, Teegarden is a very small star. With less than 1/10th the mass of the sun, Teegarden is lucky to be a star at all – any less mass and …

The Luhman 16 twins: Why brown dwarfs are cool

Dan Wild

If you’ve heard of Luhman 16AB then I salute you. And if you haven’t, then I despair at the state of astronomy education in schools today. What? They don’t teach astronomy at school? Well, if they did, how would your teacher explain Luhman 16AB? “Today we’re going to talk about brown dwarfs, stellar objects that …

You can’t be Sirius? Actually, I’m Sirius B

Dan Wild

Sirius is really two stars. A faint white dwarf, Sirius B, is locked in a dance with Sirius A, and it takes 50 years for them to orbit each other. Sirius B used to be a big guy: it was once a red giant. Except it doesn’t have quite the same mass as Betelgeuse, a …

Betelgeuse: Life as a Red Supergiant

Dan Wild

You’ve heard of Betelgeuse if you’re an amateur astronomer. It’s that flickering red star at the bottom right corner of the constellation of Orion, as viewed in the southern hemisphere, and top left viewed from the northern hemisphere. Those born in the 1980s would have heard of it via the surreal Tim Burton film, Beetlejuice. …