Stop. Just stop. There were specific reasons the IAU reclassified Pluto as a dwarf planet as opposed to a planet. This article, which keeps getting punted around the Internet as some grand new revelation: 1) fails to cite any concrete study, 2) lists reasons not exactly in line with the demarcating line between planet / dwarf planet, and 3) misrepresents some of the findings.
Let’s take apart this “article” that’s more “thought exercise” than “journalism.” Which is not to say it SHOULDN’T be written or said, but rather that it shouldn’t be misrepresented on the Internet as any formation of new facts. Which, as I’ve seen, it has been.
Poor little Pluto. In 2006 astronomers ganged up on it and voted to strip it of its planethood—but other astronomers signed a petition saying they’d ignore that vote.
Ganged up means “found at least four other objects that, while somewhat smaller, held similar characteristics to Pluto.”
Now Pluto itself seems to be fighting back. Thanks to the Hubble Space Telescope, we’ve learned that Pluto has at least five moons—pretty impressive for something that’s supposedly not a planet.
It’s fantastically fascinating that Pluto has five planets. It’s a record, so far as we know, for terrestrial worlds. Earth and Mars have moons. Venus and Mercury do not. But Pluto has five moons! That’s neat.
But the size of those moons is quite quant. The largest, Charon, has an estimated diameter of 1,205 km. The next largest, Hydra, drops to a diameter of 114 km. The smallest, Styx, has an estimated diameter of just 10 to 25 km. It’s slightly smaller than either Martian satellite, the probable captured asteroids Deimos and Phobos.
Now, another thing to keep in mind: the center of mass for the orbits is outside of Pluto. Charon is about half the size of Pluto, while the Moon is roughly a quarter the size of Earth. The center of mass for our system is within the mantle of the Earth. For Pluto and Charon, the center of mass is outside the either planet, rotating at a common point in the space between. The other satellites similarly orbit at the center of mass rather than AROUND Pluto. You could possibly, with some New Horizons data, make a case for a Pluto-Charon system wherein two dwarf planets rotate around each other, and the other satellites revolve around the system. A sort of icy Tatooine.
But it’s not the only dwarf planet system to have moons! Haumea, an egg shaped oddity in the distant Kuiper Belt, has two known moons.
Also, if having a moon or moons makes a dwarf or minor planet a candidate for full planetary status, consider 243 Ida. Its radius is a paltry 15 km, but it has a 1.4 km moon, Dactyl. It wouldn’t make it as a dwarf planet - it’s far too small and doesn’t achieve hydrostatic equilibrium. But it has a moon! Other small asteroids have objects in orbit around them. It’s how gravity works.
And new research suggests Pluto is just what we were taught long ago: the largest world orbiting the sun beyond Neptune.
In 2005 astronomers discovered Pluto’s greatest rival, Eris. It’s three times farther from the sun than Pluto. And Eris was thought to be bigger than Pluto, too. But that initial estimate may have been wrong.
Other astronomers have now analyzed methane in Pluto’s air. Yup, Pluto has an atmosphere—again, pretty impressive for something that’s supposedly not a planet—and the methane suggests Pluto is about 1,471 miles across, versus just 1,445 miles across for Eris. The new study appears in the journal Icarus. [Emmanuel Lellouch et al, Exploring the spatial, temporal, and vertical distribution of methane in Pluto’s atmosphere]
Largest known trans-Neptunian object, not the largest. We’ve only recently begun to accumulate evidence of trans-Neptunian objects, and have a small fraction of the likely-total catalog. While a WISE survey found no planetary mass bodies larger than Neptune in the Kuiper Belt, the possibility remains open for Mars sized bodies there, or Earth-to-Neptune sized bodies in the Oort Cloud, especially after the announcement of the dwarf planet candidate VP113, a.k.a. Biden. The dwarf planet candidate is small, just 465 km in diameter, but it hints at a possible Neptune sized body far, far out into the solar system. Possibly.
Also, the atmosphere of Pluto is a wisp of an atmosphere essentially made up of methane and water vapor. This isn’t, again, to discount the fascination with Pluto having an atmosphere, but Titan, a moon beyond debate, has a much thicker methane atmosphere.
We’ll find out its exact diameter in July 2015, when NASA’s first spacecraft to Pluto zips by. It’ll take lots of pictures, probably find more moons and hopefully tell us whether Pluto is indeed the king of the underworld—I mean, of the solar system beyond Neptune.
The exact calculations of its diameter likely wouldn’t thrust it back into planetary terrain. Pluto is still smaller than all the Galilean moons, our own moon, Titan and Neptune’s moon Triton. Triton, with a similar composition to Pluto, is likely a captured Kuiper Belt Object, much like Pluto.
New Horizons is sure to make some fascinating discoveries, giving us our first glimpses of the mysterious outer member of our solar system. It may discover an extensive mix of water and methane ice, more moons and features we couldn’t have predicted. But what it won’t discover is a world ready to be termed a “planet” again. That is in the realm of fantasists unwilling to accept the 2006 demotion.
Let Pluto be what it is: a fascinating dwarf planet that we have the opportunity to see up close in the next year, shedding light on a vast region beyond Neptune little understood.
My partner was on the radio yesterday discussing space junk, and sounding quite thoughtful and knowledgable while doing so. Give it a listen. She did quite a fantastic job.
In the few days since Craig Ferguson announced his departure from CBS’ The Late Late Show, a host of candidates have been suggested as possible replacements. CBS insists it’s not thinking about who will take over for Ferguson yet, while candidates like Aisha Tyler, John Hodgman, and Amy Schumer have
I hope I’m not alone in thinking that Norm Macdonald is a know-it-all jerk who defaults to juvenile humor. He’s said a lot of really problematic things like this about the Brandon Teena murder:
"In Nebraska, a man was sentenced for killing a female crossdresser [sic] who had accused him of rape and two of her friends. Excuse me if this sounds harsh, but in my mind, they all deserved to die."
Just as “integral” to his schtick on “Weekend Update” were a constant harping on black public figures like Marion Berry, OJ and Michael Jackson, who he constantly referred to as a “homosexual pedophile.” Which like, yes we get it. These people did not do very good things, but it was a repetitive animosity he exhibited toward them as part of his schtick was an odd fixation. His constant white targets aimed more at mediocrity: Frank Stallone and David Hasselhoff.
He ranted on and on about sex workers, stretching it from his “Weekend Update” schtick into Dirty Work, where of course they were racialized as Vietnamese prostitutes.
It’s all been juvenile humor at best, and he’s exhibited the sort of smart-ass personality that you later realized isn’t as funny when you view who he’s aiming at. It’s not that there wasn’t reason to joke in the public sphere about the transgressions of the time. Marion Berry, the mayor of our nation’s capital, was found smoking crack. OJ trial jokes were ubiquitous and unavoidable. Michael Jackson was all over the headlines. But it’s the way he zeroed in that reflected a reactionary undercurrent that, years later, you realize he wasn’t an irreverent comedian so much as a jerk with iffy politics.
I understand when, after a high in the 90s followed by a career mostly hocking marginal car insurance, you might want to drum up support for a bigger and better job. But Norm Macdonald’s career is not one in need of a renaissance.
I’m watching “Cosmos” with orbital-decay and we were thinking that, when the original came out, we didn’t know Pluto had four moons or a group of bodies just like it out there in the Kuiper Belt. We didn’t know there were other planets beyond our solar system yet. We didn’t know that there might be life on Europa, Enceladus or Ceres. We didn’t know the extent of water on Mars. We had never had a Hubble telescope.
By the time this “Cosmos” wraps up, we will still have more news out of the Kepler data, five to ten instances of the next earth like planet yet. A series of massive land based telescopes will give us unprecedented views of other stars and let us directly image exoplanets, something we’ve done fewer than a dozen times. James Webb Telescope will put Hubble to shame.
Basically, if we revisit “Cosmos” in 30+ years again, our understanding will have drastically changed again. If we even bother to still use TV at that point.
If you’ve been to a music festival in the last few years, you’ve probably noticed young, white people parading around in traditional Native American headdresses. It is a gross bit of cultural appropriation. Because the drummer for the Flaming Lips thought so, he was kicked out of the band after 12 years, in a controversy that involves the daughter of Oklahoma governor Mary Fallin.
I hate finding out what a waste Wayne Coyne has (publicly) become. I mean, the Erykah Badu thing, was step one in finding out about his awfulness, and here’s another chapter in that. It’s so strange to read about considering the role the Flaming Lips played during college for me. Hearing he laughed at protestors is disheartening to me.
Launched in the late 1970s, ISEE-3 could become a new platform for citizen science in space—if a couple of enterprising scientists can figure out how to talk to it.
My latest for popmech on the ISEE-3 Reboot Project.
Now that the productive Kepler telescope is down for the count, astronomers are dreaming up new techniques and missions to help them find even more planets around alien stars.
John Wenz makes a solid case for Deep Space Nine as the very gayest Star Trek.