Saturday, 8 October 2016

Star-Gayzing : A Extraterrestrial Home from Home

Earlier this week I looked at some dystopian and apocalyptic fiction by lgbt authors. I ended by asking the question of whether humanity can escape by going to another planet. Is there another planet that can support human life? Not in our own solar system. But just a few months ago a planet which might be suitable was discovered in orbit around Proxima Centauri, the nearest star to our own, in the constellation of Centaurus.

In the past decades thousands of exoplanets, planets outside our solar system, have been discovered. Not all of them are suitable for life as we know it to survive (i.e. carbon-based, liquid water-dependent life). There are a couple of hundred exoplanets which fall into the “Goldilocks Zone”, those distances from their sun which support liquid water, but fewer that are believed to be Earth-like. In fact, there are less than ten which astronomers list as being the most Earth-like exoplanets.

The nearest of these is around Proxima Centauri and has been given the name of Proxima Centauri b. The other most Earth-like, potentially habitable, exoplanets are called Gliese 667Cc, Kepler-62f, Kepler-186f, Kepler-442b, Kepler-452b, Kepler-1229b and Wolf 1061c. And that’s the problem I want to write about today. The names of planets. Most of those listed here were discovered by the Kepler Mission, hence their names. The other hundreds of exoplanets have the same “Kepler-” prefix. It’s all very confusing. But that’s not the only confusing naming system. The International Astronomical Union (IAU) who are responsible for naming extraterrestrial objects have even designated an exoplanet with the name MOA-2007-BLG-400-Lb. That takes almost as long to say as that famous Welsh town with dozens of letters in it’s name.

Recently the IAU began to give proper names to some exoplanets, not all of them Earth-like. But one gay astronomer had already attempted to name the 400 exoplanets that had been discovered before the prolific Kepler Mission was launched in 2009. The astronomer is Assistant Professor of Physics and Astronomy at California State University and his name if Wladimir Lyra (how ironic that an astronomer would have the same name as a constellation). He is also a member of the American Astronomical Society and is currently a member of its Committee for Sexual-Orientation and Gender Minorities in Astronomy.

When Wladimir Lyra came up with his list in 2009 the IAU didn’t consider giving names to exoplanets as being practical. However, last year they launched a competition to name a select group of them and the stars around which they orbit which also have no proper name. Unfortunately, none of the winning names on the 2015 IAU list matched Wladimir Lyra’s 2009 suggestions. The table below shows those exoplanets which both lists named and how the names differ. Wladimir didn’t give new names for the stars, thought the IAU did and I’ve put them in the table as well. Only the star Fomalhaut had already been given a name. The old star names are those in the “Exoplanet old name” column – just take the final letter, the planetary designation (b, c, or d), off each name.

Exoplanet’s old name
New star name
Lyra’s new planet name
IAU’s new planet name
Upsilon Andromeda b
Upsilon Andromeda c
Upsilon Andromeda d
HD 149026b
Fomalhaut b
PRS 1257+12b
PRS 1257+12c
PRS 1257+12d

The reason Wladimir Lyra chose his names are given here, and the reasons the IAU chose their names is given here.

It’s a pity that Proxima Centauri b hadn’t been discovered when these names were being decided. Wladimir Lyra chose the names of mythological Greek centaurs for his exoplanets in Centaurus. This is a shame because they are already being used as names for a specific group of minor planets in our solar system called Centaurs.

Wladimir’s list wasn’t without criticism when he produced it in 2009. A lot of his names had already been used for minor planets, satellites and asteroids. Another exoplanet he named, orbiting a star in the constellation Columba, was Peristera. A Greek-speaking colleague pointed out that Peristera is the Greek for “female pigeon”. Fortunately, this particular exoplanet is too far away and not habitable for humans so we can avoid the embarrassment to our descendants of having to escape a future dying Earth and move to the planet of the “female pigeon”!

No comments:

Post a Comment