The threesome in question, however, didn’t actually take place between the two scientists but 25 light years away in the constellations of Piscus Austrinus and Aquarius. All three members of the new threesome are stars known as Fomalhaut A, B, and C.
Fomalhaut deserves to be more well-known in the popular imagination, on a par with the Pole Star, Alpha Centauri or Betelgeuse. It’s one of the most dynamic star systems known, and is the only system where you can actually SEE another planet orbiting another star with the naked eye (you’ll need a VERY big telescope, though).
Let’s look at the Fomalhaut system before we look at the gay astronomer who helped to uncover the threesome. The illustration below shows the stars in the night sky (stars shown larger than actual size) divided into constellations, showing where all three of the Fomalhaut stars are located. All 3 stars are orbiting each other but with so many other stars in between them it seems difficult to visualise. But when you realise that the Fomalhaut stars are nearer to us than the others it becomes easier to visualise.
How big is this Fomalhaut 3-star system? The sheer size of the Fomalhaut system is itself a rarity. Very few triple stars are so disperse. That’s one reason why it wasn’t until 2013 that Fomalhaut C was recognised as being the third star in this triple system. Which brings me back to that chance meeting in Chile.
Dr. Todd Henry, a member of the Out LGBT Astronomers list, and 1994 Gay Games 5,000 and 10,000 meters champion, is founding Director of RECONS. He is also Distinguished Professor of Astronomy at Georgia State University where RECONS is based.
RECONS is the Research Consortium on Nearby Stars, and Fomalhaut, at 25 light years, is one of the nearest. The RECONS astronomers had detailed data on all of the nearest stars, including one in the constellation Aquarius called LP876-10. One of Todd Henry’s students was working on a thesis with RECONS and had obtained more detailed information about the star’s movement and characteristics.
Todd Henry had the research notes with him when he was staying at a hotel in Chile, and that’s where he met Dr. Eric Mamajek, Associate Professor of Physics and Astronomy at the University of Rochester. Dr. Mamajek, knowing Todd’s expert knowledge of near-by stars, got talking about LP876-10, which he noticed a few years earlier when he was studying the motions of all the stars in that part of the sky.
In 2013 Mamajek was hoping to discover if LP876-10 was actually linked to Fomalhaut (already known to be a double star). LP876-10 seemed to be moving in the same direction and at the same speed at Fomalhaut and he needed more detailed information. Hence the chance meeting between Todd Henry and Eric Mamajek led to the discovery that LP876-10 was indeed the third member of the Fomalhaut system, and it was renamed Fomalhaut C.
Again, it was the apparent distance from Fomalhaut A and B that led astronomers to think that LP876-10 wasn’t part of the system – it was so far across the sky, and in a totally different constellation. In fact, against the deceptive, flat-looking night sky you can put 11 full Moons between Fomalhaut A and the new Fomalhaut C.
The whole Fomalhaut system is an amazing place. There are bright dust and debris rings and comet clouds, and each of the 3 stars is different. Fomalhaut A, star known to the ancient Arabs as “fum al-hawt” (“mouth of the fish”), is about twice the size of our Sun but 16 times brighter. One planet was discovered orbiting on the edge of a dust cloud and comet belt. Fomalhaut B is a variable star, fluctuating in brightness due to an orbiting dust cloud. Fomalhaut C is red dwarf star and, like Fomalhaut A, has a dust ring.
Todd Henry’s work at RECONS is helping us to understand our nearest interstellar neighbours. By studying the planet, and others orbiting other stars, he is following on from his earlier research into the search for extraterrestrial intelligence (SETI). I’ll return to Todd Henry and SETI later in the year.
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