Finally, Really, You’re Invited to Help Name Distant Planets

It's a new policy for the International Astronomical Union.
Kepler-22b, just 2.4 times the size of Earth, is the first planet known to comfortably circle in the habitable zone of a sun-like star. Scientists do not yet know if the planet has a rocky, gaseous, or liquid composition. It's possible that the world would have clouds in its atmosphere, as depicted here. NASA/Ames/JPL-Caltech

The world known officially as PSR B1620-26 b orbits a binary star system about 12,000 light-years away. With an estimated age of 12.7 billion years, PSR B1620-26 b is considered one of the oldest planets in the universe, more than twice as old as our solar system. Astronomers found it in the 1990s because of the tug it exerts on its two stars, a pulsar and a white dwarf.

As a name, PSR B1620-26 b doesn’t exactly have a ring to it, though. Some people instead call it Methuselah, after the oldest living person according to biblical accounts.

Next year, you’ll be able to vote on that name, and maybe have it officially sanctioned by the International Astronomical Union, in a new project under the Zooniverse. This is a big change for the largest astronomy society in the world, and an exciting one for citizen science.

To participate, you have to be involved in an astronomy club or non-profit organization, which can register with the IAU and then submit names for about 30 planets of the IAU’s choosing. Voting will happen next spring and summer, and the IAU will announce the new nicknames at a special ceremony at its 29th General Assembly next August, the biggest astronomy meeting on Earth.

In this month’s issue of Popular Science, I argued that the IAU should embrace the public’s desire to get involved like this. The IAU’s Public Naming of Planets and Planetary Satellites Working Group held meetings earlier this summer to that end, and announced the new policy on Wednesday. The IAU approached Chris Lintott, an astronomer and founder of the Galaxy Zoo, precursor to the hugely popular Zooniverse citizen science website. Lintott had already suggested that citizen science could benefit the IAU, according to Lars Lindberg Christensen, the IAU’s press officer. “I’d say it grew organically from our discussions,” Christensen told Popular Science.

Chalk one up for crowdsourcing: With the NameExoWorlds project, we all get to have a say. This is a welcome change, and one that brings us all a little closer to space. But it took a long time and a bit of controversy to get here.

Watery Worlds Of Kepler-62

Since its founding in 1919, the IAU has been the official arbiter of celestial nomenclature. Its members are professional astronomers who choose designations for new moons, asteroids and geologic features on other celestial bodies, so scientists know they’re all talking about the same things. But this power sometimes clashes with public sentiment — most infamously when IAU members essentially demoted Pluto, by changing the definition of planet.

Tensions flared up again last year, after a new, for-profit astronomy fundraising company called Uwingu (it means “sky” in Swahili) started getting people excited about exoplanets. Astronomers have found thousands of candidate planets in the last five years, with hundreds of them confirmed — but they have pretty boring names, like Kepler-62, HD 40307 g, and our friend PSR B1620-26 b.

Uwingu sponsored a contest in which people could pay $4.99 to suggest better names, and 99 cents to vote on them. The goal was to build a database of new names while raising money for cash-strapped astronomy research programs.

The IAU took umbrage, reminding Uwingu in a less-than-friendly manner that it was the only organization responsible for such names. Part of the reason for this distaste was the IAU’s long history battling fraudulent companies selling “official” naming rights to stars or lunar real estate. But Uwingu insisted it was different: Profits go to scientific research, it’s run by professional scientists who are IAU members, and it makes no claims of official naming recognition beyond its own purview. Its leaders also pointed out that astronomers and other scientists grant “unofficial” names all the time — there’s a long history of cartoon characters, authors and generally nonsensical names used on the moon and Mars.

The new IAU contest doesn’t mention Uwingu by name, but it does include a rule that any participants must be non-profits. By definition, that will exclude Uwingu, which is a for-profit company. There’s no reason why a name previously submitted to Uwingu’s database can’t be submitted in the Zooniverse one, but it would have to come through a non-profit organization.

“The IAU strongly believes that naming of astronomical objects should be free for all and have a wide international participation (which also implies no exchange of funds),” Christensen said.

Either way, last year’s debate was really larger than a spat between an international organization and American researchers. The more philosophical question was, who owns space? The answer should be all of us. People have been naming planets, stars and landmarks on Earth since time immemorial. Explorers settling the Americas named new cities and mountains for family members, leaders, patrons, hometowns, and themselves, and didn’t get official permission or decree to do so. Why not do the same for the likely billions and billions of exoplanets in the Milky Way?

Uwingu’s planet contest — and a second one, asking for new names for craters on Mars — involved thousands of people, demonstrating how much the public cares about this. The IAU’s new Zooniverse project is in response to increased public interest, according to the organization. “The intention is that millions of people worldwide will be able to take part in the vote,” the official announcement says.

There are a couple caveats. In a somewhat surprising twist, the IAU is only using 305 exoplanets that were discovered before Dec. 31, 2008 — so ruling out the 977 planets spotted by the prolific American planet-hunting Kepler Space Telescope, which launched in 2009. By contrast, the COROT space telescope, a French satellite, made several discoveries between first light in January 2007 and the end of 2008.

Christensen said in an email that those older planets are “in general the most reliable exoplanet detections.”

“We are using the first batch of 305 exoplanets to find out how to best work with the public on the naming process. It will take quite some years to name them all, but if all goes well, it is not impossible that the IAU will want to expand with more exoplanet systems,” he said. “Naturally there are no guarantees that all of the 305 exoplanets in this list will stand the test of (more) time. Science changes all the time, and these objects are notoriously hard to detect.”

His point is punctuated by the recent news about Gliese 581 g — what an exciting world it would have been, if it weren’t just a sunspot.

Once the votes are counted next year, the winning names will be officially sanctioned by the IAU, but they won’t replace the official designations. That just means people will be able to use their nicknames in parallel with the existing nomenclature. So old PSR B1620-26 b will be known as both PSR B1620-26 b and, maybe, Methuselah.