Plutoid names in different orbit
With Greek and Roman gods running short, the newest dwarf planet is
named after a Polynesian fertility god.
By ANNE MINARD
Special to the Daily Sun
Saturday, July 26, 2008
Pluto might have been cast out of the lineup of solar system planets,
but the Flagstaff discovery is anything but lonely.
Pluto has so many companions in the outer solar system, in fact, that
astronomers have run out of Greek and Roman names to call them. So
they're getting multicultural.
The International Astronomical Union has announced the official name
of the fifth dwarf planet, discovered in 2005 by Mike Brown's team at
the California Institute of Technology: Makemake.
Pronounced MAH-kay-MAH-kay, the name refers to a Polynesian creation
god.
Ted Bowell is a Lowell Observatory astronomer who presides over the
IAU's Division III, which oversees research in planetary systems. As
part of his role, Bowell is also involved with the IAU's two naming
committees that must approve new dwarf planet monikers.
"It looks as though we are starting to establish the idea that large
distant objects in the solar system be named after creation gods," he
said.
All except for the ones that orbit two times for Neptune's every
three, that is. Those planets, locked into the same rhythm as Pluto,
are to be named after underworld mythological deities in honor of the
former planet.
CELESTIAL PUZZLER
Brown said he was stumped for a time about what to call his latest
discovery. For the two years it was known in scientific circles as
2005 FY9, Brown was calling it Easterbunny -- because he found it a
few days after Easter.
"Suddenly, it dawned on me: the island of Rapa Nui," Brown said,
referring to the aboriginal name for Easter Island. "Why hadn't I
thought of this before?"
The name Makemake clicked for Brown and it clicked for the IAU, which
adopted the name just a month after deciding to use "Plutoid" to
label Pluto and other dwarf planets beyond Neptune.
The IAU coined the term "dwarf planet" in 2006, to accommodate Pluto
and other objects in its neighborhood -- called the Kuiper Belt --
that were then being discovered. But the new distinction also
included Ceres, the giant asteroid orbiting between Mars and Jupiter.
Now Ceres is the lonely one, as the only dwarf planet that's not a
Plutoid.
Makemake's recognition couldn't have come too soon for Brown, who
submitted his idea six months ago.
"While a rose by any other name would surely smell as sweet, the
Kuiper belt object/dwarf planet/Plutoid formerly known mostly as 2005
FY9 now smells a good bit sweeter to me," he wrote on his blog.
ONLY AN ASTRONOMER COULD LOVE
Makemake was the chief god of the Tangata manu bird-man cult,
incarnated as sea-birds and symbolized as a man with a bird's head.
Makemake the dwarf planet is one of the largest objects discovered so
far in the outer solar system. It's about two-thirds the size of
Pluto and only slightly dimmer. The dwarf planet is reddish in color,
and astronomers believe the surface is covered with frozen methane.
"A lot of these objects have had sort of an obvious thing to hang the
name on," Brown said. Eris, for example, needed a name just after the
IAU's demotion of Pluto and the public outcry that followed.
Scientists had fairly exhausted the cadre of Roman and Greek god
names, but Eris remained: the goddess of discord and strife.
"Clearly I believe in astrology," Brown joked, "because that had been
waiting for us for a long, long time."
A WELCOME SHIFT
Brian Marsden has recorded the names of more than 12,000 asteroids
and other planetary bodies during his 30-plus years at Harvard
University's Minor Planet Center. He also sits on both IAU committees
that must approve new dwarf planet names: the Committee on Small Body
Nomenclature and the Working Group for Planetary System Nomenclature.
Three other Flagstaff astronomers occupy positions on the committees:
the U.S. Geological Survey's Jennifer Blue, Lisa Gaddis and Ken
Tanaka, though the latter two members only approve names for Mars or
the moon.
The Lowell Observatory's Bowell said Makemake was nearly unanimous
among the committees, and the only discussion came over whether to
hyphenate, combine or separate the two "make" parts.
"By having Makemake not be a Greek or Roman name," Marsden
added, "we've got away from that idea for these dwarf planets, and I
think that's good."
For his part, Brown has written quite a few names in the stars.
Among them are Quaoar, a creation force of the Los Angeles Tongva
tribe; Orcus, the earlier Etruscan counterpart to Pluto; Sedna, the
Inuit sea goddess, and Eris.
Brown may have at least one more name in the pipeline -- but first
the IAU will have to decide whether he got swindled or just scooped
by a competing Spanish team claiming to discover 2003 EL61 first.
ON THE WEB IAU Web site: www.iau.org Information about Pluto and the
other dwarf planets: www.iau.org/ public_press/themes/pluto Lowell
Obervatory: www.lowell.edu