Sky Matters: Ireland has the chance to name a star and a planet - any ideas?

We are all familiar with the names of the eight planets that orbit our sun (and poor old Pluto, which remains somewhat controversially re-classified as a dwarf planet).

Those names come from ancient Greek and Roman mythology.

In recent years, astronomers have discovered thousands of new planets, all orbiting stars other than the sun.

And it turns out that many of these stars have planets orbiting them. As part of the celebrations of its first 100 years, the International Astronomical Union — the only organisation which is legally entitled to name new stars and planets — has offered each country the chance to name a star and the planet which orbits around it.

This is, in many ways, an opportunity for us to dig into Irish mythology to seek out names that resonate with us.

For Ireland, that star currently has a rather unexciting name — HAT-P-36. And orbiting that star is a planet with an equally unremarkable name of HAT-P-36b. We know comparatively little about HAT-P-36 — the star, not the planet, confusing isn’t it? — but we do know it’s about the same age and size as our own sun.

We know very little about HAT-P-36b — the planet, not the star, now you can see why we need some easier way to distinguish them — other than its size, which is almost twice that of Jupiter, and the fact that it whips around HAT-P-36 (the star…) in a mere 1.3 days.

In other words, a year on HAT-P-36b (the planet… you may be getting tired by now) lasts a mere 32 hours. We don’t know what the length of day is on HAT-P-36b, but we do know that we are seeing both the planet and the star it orbits as they were just over 1000 years ago — that’s how long it has taken the light to reach us.

If you would like to be in with a chance to name Ireland’s first star and planet, you will find all the details on the Blackrock Castle Observatory website sciencespace.ie/nameexoworlds-ireland/. The closing date for entries is October 10 and entries are free.

Given the relatively recent debacle with the “boaty mcboatface” ship-naming competition, there are some “helpful” naming rules and there is a panel of expert Irish judges who will filter entries down to a list that will then be voted on by the general public.

The selected name for the star and planet will be announced for all countries in December by the IAU, along with the names of the individuals who nominated them.

HAT-P-36 is too faint a star to be seen by the unaided eye, but it is visible in binoculars or a small telescope. HAT-P-36b, like all planets beyond our solar system, is too faint to see without highly specialised equipment and indeed in its case, it’s so faint that we can only detect it when it passes in front of HAT-P-36 and blocks out some of that star’s light.

But that shouldn’t deter us from being excited by the possibility to name this star and planet.

It’s like a piece of Irish celestial real estate, admittedly rather difficult to reach — travelling at the speed of our fastest spacecraft to date it would take about 5m years to get there.

On a totally separate note, keep an eye out for the Orionid meteor shower which peaks on the night of October 21. This is a rather unpredictable shower, but when its good its very good.

The best way to observe it is from a dark location — that can be your back garden — and while the meteors will appear to come from the constellation of Orion they can appear anywhere in the sky.

- More details can be found on the general Blackrock Castle Observatory website, bco.ie