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Not so long ago, on the far away moon of Charon, a tiny space probe spied a strange energy signature emanating from a crater named after Luke Skywalker’s sister. No, it wasn’t midi-chlorians. Organa crater, named for Star Wars heroine Princess Leia, is actually coated with ammonia, though scientists are still baffled as to why.
Ammonia is pretty abundant in the galaxy. Because it stays liquid at very low temperatures, many scientists believe it is behind a lot of the geologic activity on icy worlds like Charon. In fact, based on telescope observations from Earth and photographic evidence of geomorphology taken from New Horizons, scientists expected the faraway moon to be covered with the stuff. “But we haven’t seen it everywhere. This crater is an exception,” says Will Grundy, astronomer at Lowell Observatory in Arizona and ice expert for the New Horizons mission.
The source of the ammonia is a mystery, but Lowell and his co-investigators shared a few hypotheses. “One speculation is that this is just a more youthful crater than the rest,” says Grundy. In this scenario, ammonia would be everywhere under the top layer of Charon’s surface. Organa could be so young that space radiation hasn’t yet destroyed the underlying ammonia exposed by the initial meteor strike. “But we really don’t know the timescale at which that happens,” says Grundy.
Another idea is perhaps the meteor that created Organa crater was ammonia-rich, and left some of the stuff behind. The final speculation is that Organa is roughly the same age as other Charonian craters, but happens to be located over an unusually rich subsurface smear of ammonia. “But these are all pretty speculative, and I’m not sure if it’s useful to weigh one over another,” says Grundy.
Grundy says with better imagery the New Horizons team could probably tease out some clues from the geomorphology surrounding the crater, but that’s not likely to happen. New Horizons was three times as far from Charon as Pluto during the flyby. “We’re never going to get as high a resolution as we have with Pluto,” says Grundy.
Organa’s ammonia signature is even more striking compared to a nearly identical crater to the south, called Skywalker. As of press time, there was no indication that the sibling craters had ever accidentally kissed.
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The first crewed mission to Pluto is going to be a master class in homesickness. After traveling 4.7 billion miles to the icy rock, those future pioneers—breathing bottled air, bundled in awkward space clothes, buoyant in low gravity—will have little to remind them of home. But upon landing, they might just ease their pangs of longing by gazing up into the dwarf planet’s sky—which, scientists now know, is blue just like Earth’s.
NASA broke the news today by sharing the above photo of Pluto’s cerulean halo, taken in July by the New Horizons spacecraft.
Like Earth’s heavenly hue, Pluto’s blue sky is caused by tiny, sunlight-scattering particles in the atmosphere. Those particles probably begin as molecular nitrogen (which Pluto is constantly emitting) and other trace gases. The sun’s ultraviolet rays break down and ionize these molecules, which then combine into larger (though still microscopic) particles.
The particles aren’t blue themselves; they’re reddish to grey, and are heavy enough that they eventually fall back down to the dwarf planet’s surface.
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But wait! There’s more! See those conveniently-colored blue blobs on the above close-up? Those are frozen water, confirmed by combining spectral infrared and visible light data taken by two of New Horizons’ imagers. What’s compelling to scientists (besides the fact that water exists) is why it appears where it does: on rocky outcrops near craters, and between mountains.
Another mystery is the water’s hue, which appears bright red in color imagery. The New Horizons team thinks this indicates some sort of relationship between the surface ice and those atmospheric particles responsible for Pluto’s blue sky.
Maybe I’m biased, but those pretty skies and chunks of water make Pluto seem like a pretty good setting for Hollywood’s next lost-in-space blockbuster. Damon, you up for getting stranded on yet another world?
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Like Pluto, Charon is not a planet. But who needs recognition from the stuffy, earthbound International Astronomical Union? Especially when you’ve got ice volcanoes?
That’s right, ice volcanoes. See, Charon’s two hemispheres are so different that scientists’ best guess for why one is so much smoother is that ice erupts from below the dwarf moon’s surface. Bordering the the slick lowlands is a massive canyon system, which you can see in the video above.
The flight begins high above Mordor, which is what Charon-ologists have named the dark spot in the moon’s polar highlands. New Horizons’ atmospheric scientists believe that Mordor might actually be nitrogen deposits captured from Pluto (which is constantly shedding the stuff).
Then the flight swoops into the canyons, a system that seems to extend at least 1,000 miles. The canyons might even completely encircle Charon—sort of like the hug the moon deserves from those meanies at the IAU.
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Caption: This high-res image shows Charon at 1.8 mile resolution. NASA/JHUAPL/SwRI
Caption: New Horizons LORRI imager captured Charon’s details, then its Ralph/MVIC imager filled in the color. NASA/JHUAPL/SwRI
Caption: Pluto and Charon are at proper relative sizes in this image. At their proper distances in space, Charon would appear much smaller. NASA/JHUAPL/SwRI
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Admit it: You were a little envious of New Horizons when it flew through the Pluto system in July. (Probably less so regarding the nine preceding years of isolated hurtling.) Lucky for you, NASA keeps dropping new imagery. This flyby experience gets more vicarious by the week.
On Thursday the agency released the best images so far of Pluto’s moon Charon. Its surface features indicate some lively geologic activity. One half of the planet (let’s refrain from imposing our Terran notions of “north” and “south” on this alien world) is craggy and mountainous, with evidence of landslides.
The landscape below the canyon is a lot smoother than above. Fewer craters indicates that Vulcan Planum, as the New Horizons team is calling it, is probably a lot younger. Nobody expected active geology on Pluto or its satellites, so scientists are still working out what causes the subsurface roiling. But in Charon’s case, they suspect cryovulcanism. That’s right: ice volcanoes. A layer of heavy rock presses downward onto a thick layer of frozen water. Sandwiched against rock below, that ice ruptures through Charon’s surface where the stuff flows like lava.
A sprawling system of cliffs, gulches, and fractures separates Charon’s hemispheres–scientists estimate that’s more than 1,000 miles of geologic tumult. (What’s up with other worlds and marquee features, by the way? Mars has its volcano, Jupiter its spot, Pluto its heart…) Combined, the canyon is four times longer than the Grand Canyon on Earth, and in places is twice as deep. It would make for great rafting, if the water there didn’t flow like lava.
The second picture has a closer look at Charon’s varied landscape, including the landslide evidence. The third is a composite showing Pluto and Charon together. See Charon’s reddish polar area? Pluto’s equatorial region has a similar color; scientists believe the two are somehow related.
NASA still has plenty of New Horizons data to share. Except for the not freezing to death or suffocating, it’s almost like being there.
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It’s only been two months since New Horizons whizzed past Pluto, some 4.7 billion miles from Earth. Now, the space probe is in the process of sending back tens of gigabits of data collected during the flyby, including increasingly kick-ass photos of the icy rock’s surface.
The most recent images released by NASA show the dwarf planet backlit by the sun, revealing mountain ridges and atmospheric haze—lots and lots of haze. They also offer a more detailed look at Sputnik Planum, the smooth, icy expanse that looks like a big heart. Enjoy, and keep coming back for more photos—they’ll keep coming in over the next year.
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Caption: Just after it whizzed past Pluto, New Horizons took this photo of the dwarf planet backlit by the sun. The image shows mountain ridges and atmospheric haze—lots and lots of layers of atmospheric haze. NASA/JHUAPL/SWRI
Caption: Icy mountains (left) contrast with the smooth expanse of Sputnik Planum (right), probably covered in nitrogen ice. NASA/JHUAPL/SWRI
Caption: Sunset on Pluto! The sun shines through the “fog” near Pluto’s surface. The shadows come from hills and mountains. NASA/JHUAPL/SWRI
Caption: This is the heart-shaped bright spot on Pluto, also known as Sputnik Planum. The white color likely comes from nitrogen ice. NASA/JHUAPL/SWRI
Caption: Red arrows show where a glacier flows into Sputnik Planum. Blue arrows point to the edge of the glacier. NASA/JHUAPL/SWRI
Caption: Another view of the glaciers, showing more detail. NASA/JHUAPL/SWRI
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If you ever even for a minute thought Pluto was an inert little ice ball, banish those thoughts now. A whole new batch of Pluto photos from New Horizons has some of the best views yet of the planet’s atmosphere and exotic ices.
A geeky aside: These new photos come from MVIC, a camera that’s part of Ralph, New Horizons’ main “eyes” and color imager. The last batch of New Horizons photos was from a different instrument, the Long Range Reconnaissance Imager or LORRI, which as its name implies was built for looking at Pluto from far away. With Ralph today, we’re getting up close and personal with Pluto.
And you know what scientists are super excited about seeing with Ralph? Atmospheric haze. Just as the Earth has fog and clouds and a water cycle, Pluto appears to have a nitrogen cycle. A bright spot, informally dubbed the Sputnik Planum, is probably covered in these exotic nitrogenous ices. And those swirls? Nitrogen glaciers. Looking good, Pluto.
In the best LORRI image we have down yet we could say there were “more than five” layers. In this MVIC image we can see many, many more.
— Alex Parker (@Alex_Parker) September 17, 2015
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Right now, New Horizons is speeding toward its next target, Kuiper Belt Object 2014 MU69. But while it focuses on avoiding collisions with scattered, icy bodies throughout the belt, it’s also sending back all the data it collected while flying by Pluto back in July.
The space probe’s Earth-bound guides received the first of that data—the beginning of a year-long intensive downlink—last week. Enjoy some of these great images, and get ready: You can expect much more where that came from.
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Caption: This patched-together image of Pluto shows New Horizons’ views of the dark, cratered Cthulhu Regio below Sputnik Planum’s bright, left lobe. NASA/JHUAPL/SWRI
Caption: A large region of jumbled, broken terrain on the northwestern edge of Sputnik Planum (that’s the big heart). NASA/JHUAPL/SWRI
Caption: Scientists are still working out what causes these enigmatic fields of dark, aligned ridges. If they are dunes, that could mean Pluto has wind. NASA/JHUAPL/SWRI
Caption: More detail of Pluto’s big heart-shaped ice plain, Sputnik Planum. NASA/JHUAPL/SWRI
Caption: Two different versions of an image of Pluto’s haze layers, taken by New Horizons as it looked back at Pluto’s dark side. NASA/JHUAPL/SWRI
Caption: Pluto’s bright, high-altitude atmospheric haze produces a twilight that softly illuminates the surface before sunrise and after sunset. NASA/JHUAPL/SWRI
Caption: Charon’s surface indicates a surprisingly complex geological history, including tectonic fracturing and mountainous uplift. NASA/JHUAPL/SWRI
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They’re here! Last Saturday, New Horizons started the intensive process of sending data from its July flyby of the Pluto system back to Earth. During its closest approach—about 7,800 miles from Pluto’s surface—the spacecraft collected tens of gigabits of data. That includes photos, spectra, and atmospheric readings. Now that data is coming back bit by bit.
Like, literally. The probe is so far away that it can only send data at a rate of around 1 to 4 kilobits per second. The probe has been sending back lower data-rate information from its energetic particle, solar wind and space dust instruments since late July, but Saturday marked the beginning of a new, year-long download of hi-res images and the like.
That should be plenty of time to clear the hard drives before New Horizons does its next flyby. Did you hear? The little probe will reach Kuiper Belt Object 2014 MU69 in January 2019.
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New Horizons has a new destination! The spacecraft, as you might remember, whizzed by the former planet known as Pluto earlier this summer. NASA has now picked its next stop: a small, cold Kuiper Belt object called 2014 MU69 that is nearly a billion miles beyond Pluto.
Although the trip to Pluto has been carefully planned, the trip beyond has been…less so. Kuiper Belt objects at the edge of the solar system are enticing destinations because they’re made up of primitive material largely unchanged since the solar system’s birth 4.6 billion years ago. NASA had been looking for a KBO that New Horizons could visit since 2011. But none of the ground-based telescopes turned up anything that the spacecraft could reach with its remaining fuel.
With time running out, NASA finagled observation time on the Hubble Space Telescope in the summer of 2014. Then, finally, Hubble found five potential targets—eventually narrowed down to two.
2014 MU69 was known as potential target 1, or PT1, because it is easier to reach. But the other option, PT3, looked brighter in the sky, meaning it could be bigger and more interesting. “We have to weigh the risk of something barely reachable and another one that is smaller but easily reachable,” said Hal Weaver, a New Horizons project scientist, back in July. With a multimillion dollar spacecraft on the line, NASA evidently went with the safer bet.
NASA will point New Horizons toward 2014 MU69 with four maneuvers this fall. It’ll reach the target by January 2019. Because of the bureaucratic rules that govern NASA’s budget, though, the official proposal for the 2014 MU69 mission isn’t due until 2016. Of course, it’d be too late to maneuver New Horizons by then.
For now, NASA is also teasing the possibility of an extended mission—even beyond 2014 MU69. Of course, one New Horizons scientist also couldn’t resist a reference to The Martian.
To make this work, we had to channel Mark Watney and “science the $^!§ out of it.” https://t.co/L8KuSK1rQU
— Alex Parker (@Alex_Parker) August 28, 2015
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Pluto has a problem: Its thin, nitrogen atmosphere shouldn’t be there. Ultraviolet rays from the sun should have knocked it away, molecule by molecule, in the dwarf planet’s first few thousand years. Four billion years later, Pluto’s atmosphere is still there, a gauzy interplanetary mystery.
Okay, it’s really scientists who have the problem, because it’s not like there are nitrogen-breathing Plutonians down there pacing worriedly over impending suffocation. Right, NASA? Right?!? No, all worrying has been purely academic, expressed in papers like the one published earlier this month by a pair of New Horizons scientists who examined the trio of prevailing theories behind the atmosphere’s perplexing replenishment.
High noon on Pluto looks like dusk on Earth. But even that small amount of solar energy is enough to turn frozen nitrogen on Pluto’s surface into gas. Once aloft, Pluto’s gravity is too weak to keep the particles from being blown away by ultraviolet radiation. (In case you’re wondering, Earth’s mass is enough to keep its atmosphere mostly safe from getting blown off into space.)
Pluto has been around for about four billion years, and according to the best math, it should have lost about 7,000,000,000,000,000,000,000 grams of nitrogen (give or take a zero) since then. But scientists currently estimate that the planet has about 30,000,000,000,000,000 grams of nitrogen atmosphere, and loses about 1,500,000,000,000 grams each year. “Basically, it would take only a few thousand to tens of thousands of years to lose that atmosphere,” says Kelsi Singer, post-doctoral researcher at the Southwest Research Center and co-author of the paper. Basically, that’s not a very long time.
Considering that Pluto has been around for more than four billion years, the odds are pretty friggin’ slim that humans would meet the dwarf planet during its brief phase of atmosphere-having. No, something is replenishing the supply. Scientists, you got some ‘splaining to do.
There are two basic mechanisms for resupplying Pluto’s atmosphere: “You can either bring stuff in from the outside or bring stuff up from the inside,” Singer ‘splains. Comets are a handy mechanism for both categories, as they can deposit nitrogen when they impact, or punch holes through the surface to expose quantities of the frozen gas. Singer is an impact expert, so she did the calculations for how much nitrogen a comet would shed, or dig up, upon impact. Her co-author Alan Stern, studies atmospheres (among other things) and ran the numbers for gas loss. But even with their most conservative estimates—the maximum number of comets, the deepest of impact craters—nothing from off planet could cover the deficit of nitrogen loss.
Instead, they offer that the nitrogen is being replenished through more conventional geologic activity like cryovolcanism or tectonic action. But nobody yet knows what is behind this geologic churning, as Pluto is too small and too old to be holding much remnant energy from its formation. It’s also too far from any planetary body that would be large enough to tidally churn its innards. Something else inside the dwarf planet was causing exhalations. Does a Great Old One stir under the dark equatorial region, ominously nicknamed Cthulhu Reggio? It would explain the Sleeper of R’lyeh’s long absence…
Perhaps wisely, Singer and Stern do not explore that chilling hypothesis.
The most likely battery for Plutonian heat are huge chunks of uranium or potassium wedged in its rocky core. “Those will emit heat as they break down, and the heat has to go somewhere, so it causes local melting,” says Will Grundy, a planetary scientist, ice expert, and French cheese connoisseur at Lowell Observatory in Arizona.
The authors submitted their paper back in May, just as New Horizons was sending home its first images of Pluto. Since then, the probe’s cornucopia of data has supported Singer and Stern’s geologic hypothesis. “We do seem to be seeing a good deal of recent geologic activity on Pluto, so that’s not a bad sign for our paper,” says Singer. Things will look even better come September and October, when they can make better estimations of the impact rate based on the lossless data showing the dwarf planet’s craters. “We also get data from particle and plasma, that will help us calc the rate of atmospheric escape,” she says.
And every bit that arrives will blow away the mystery of Pluto’s missing molecules.
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Earthlings have a sadly unsophisticated view of ice. Terrestrial types mostly think about it in terms of water ice—solid, cold, slick to the touch as it begins to melt in their warm, fleshy hands. But not Plutonians. If you lived on Pluto, you’d have as many names for ice as the Eskimos have for snow: words for carbon monoxide ice, nitrogen ice, and methane ice, all with different properties.
Today’s photos back from New Horizons put the spotlight on those frozen solids. In this top false color image, you can see just how much compositional variety defines Pluto’s surface—from the bright white of the carbon monoxide ice in the middle of Pluto’s “heart,” now officially called Tombaugh Regio, to the bands of colors likely created by the seasonal transport of ices from equator to pole. The blueish spots might be ices that have traveled from the left lobe of Pluto’s heart.
And then there’s the ice’s geological activity. “Water ice at Pluto’s temperatures won’t move anywhere,” says New Horizons co-investigator Bill McKinnon. “But these ices are geologically soft and malleable, even at Pluto conditions.” In new high-resolution images from the LORRI camera, scientists can see the flowing solids—including nitrogen ice—in the vast Sputnik Planum interacting with towering mountains, flowing between them and even filling in old impact craters.
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“We knew there was nitrogen ice on Pluto, but to see evidence for recent geological activity is simply a dream come true,” says McKinnon.
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Feast your eyes on this one. Photos from New Horizons’ mission to Pluto have dwindled to a trickle, but the team has planted a flag in the sand with this most recent image, taken by the spacecraft after its closest approach to the dwarf planet. “You can only get this image by going to Pluto and looking back,” says principal investigator Alan Stern. Casting a dramatic over-the-shoulder glance toward the sun after it had passed Pluto, this is New Horizons’ way of saying “I was here.”
While Pluto’s backlit silhouette is beautiful, this is more than a simple glamour shot. See that band of light surrounding the rock? That’s Pluto’s atmosphere, and looking closely at its illumination tells New Horizons’ atmospheric team some surprising things about its size and its makeup. “This is the image that almost brought tears to the eyes of the atmospheric scientists on the team,” says co-investigator Michael Summers.
For 25 years, scientists have known that Pluto has an atmosphere. But in this image, the New Horizons team could pull out discrete layers of haze—small particles in the atmosphere, scattering sunlight. First off, the entire haze layer is at least 100 miles high, five times higher than the team predicted. And that layer seems to be broken into layers, one up about 30 miles and the other about 50 miles up.
Those two layers may provide clues about the red color on Pluto’s surface. Atmospheric scientists think that methane in Pluto’s atmosphere gets bombarded by UV light, which helps to form other compounds like ethylene and acetylene that finally end up as red-hued hydrocarbons called tholins. Those heavier particles in the low atmosphere eventually fall to the surface, giving Pluto its distinctive hue. Studying the layers in Pluto’s atmosphere should help explain that chain of reactions better—and the team has a year’s worth of data on the way to help.
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If the first close-up images of Pluto’s mountain ranges sent home by New Horizons seemed a little underwhelming, it might have been because you couldn’t really get a sense for their scale in a two-dimensional photo. Now NASA has released an amazing simulated video of the space probe’s flyover, helping those features pop out like they should.
Those mountain ranges have a name now: Norgay Montes, named after one of the first people to summit Mount Everest, Tenzing Norgay. Some of the peaks seen in this flyover are up to 11,000 feet tall—an impressive stat on its own, but especially so when you consider they’re probably made of ice (the frozen nitrogen and methane that covers most of Pluto’s surface would collapse under themselves at that elevation).
The video continues and transports you to the so-called Sputnik Planum, a vast plain of unexpectedly craterless surface that suggests Pluto is geologically quite young (if you can call 100 million years old young). The plain lies within the region now officially named Tombaugh Regio, after Pluto’s discoverer—but to us, it’ll always be Pluto’s heart.
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Well hel-lo, Charon. NASA just released the latest photo of Pluto’s largest moon in stunning new detail, and this one’s got a closeup of an unusual beauty mark. To us, it strongly resembles an outie bellybutton. But if you’re not quite seeing it, you could also say it looks like “a large mountain sitting in a moat,” as New Horizons scientist Jeff Moore describes it. And his team has no idea what it is.
The closeup, shown above next to an earlier capture of Charon in its entirety, covers about 240 miles from top to bottom, and boasts some handsome craters as well. New Horizons took this image on Tuesday morning about an hour and a half before its historic closest approach to Pluto—about 49,000 miles away from Charon—and compressed it so the probe could send it more quickly back to Earth. So get ready for even better shots of Charon; the spacecraft is in the process of sending the real-deal, high-resolution images.
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Today the New Horizons team treated the world to new images of Pluto, Charon, and Hydra, all taken by LORRI, New Horizons’ main imager. But LORRI’s all grey. Still to come are images featuring the full visible light spectrum, plus near infrared from RALPH, the probe’s color and infrared imager.
Nothing new from RALPH just yet, but as a tease of what’s to come, New Horizons’ planetary ice expert Will Grundy, of the Lowell Observatory, showed off some methane readings that were sent over in the probe’s final broadcast before it went dark for its July 14 flyby.
The bright blue, red, and black pixels—overlaid on a LORRI basemap—represent methane ice accumulations. These colors represent data from just three of RALPH’s 256 infrared wavelengths. As such, they don’t say much more than that Pluto has different types of ice. “All I’m showing is the diversity of terrains,” says Grundy.
But there are some interesting clues. For one, Grundy says that the colors in the ice cap look a lot like the colors in the right side of the giant heart—which today New Horizons informally named the Tombaugh Regio after Pluto’s discoverer, Clyde Tombaugh. “The ices do have distinct properties, different melting points,” Grundy said at an earlier conference, speaking more generally about Pluto’s surface.
All vague, all tantalizing, and taken in context with some of the other news revealed today—that Pluto has massive mountains made of water ice and could be geologically active—these slim details hint at big things to come.
Pluto may be cold, small, and far away, but the world is anything but dull.
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Over the course of New Horizons’ nearly decade-long journey to Pluto, mission scientists at NASA, Johns Hopkins, and the Southwest Research Institute have watched the icy rock grow from mere pixels into a real place, with topography and geology and all the things you’d expect from a planet (even though it technically isn’t one).
Today, after the space probe completed its closest approach to Pluto’s system, the New Horizons team released a new image—the most detailed ever—that shows mountains on the dwarf planet’s southeastern hemisphere. NASA’s Goddard Space Flight Center posted this timeline of Pluto photos, making the accomplishments of the New Horizons team that much more visceral. Take it all in.
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Maybe you still haven’t figured out how to say the name of Pluto’s largest moon. Let me help. It’s pronounced “WOW.”
I don’t want to interrupt your gasping with too many words, but here are some quick stats on the shot.
Draw your eyes to the dark area around the moon’s north pole. “Informally we’ve been referring to that as Mordor,” says Cathy Olkin, one of the mission’s top planetary scientists, to the delight of everyone. Trace your gaze down the right curve until you reach a notch, at about the 2 o’clock spot. That’s a canyon. A big one, about four to six miles deep.
And that’s not all. Move your eyes down and in and follow the huge sash of canyons banding across the planet’s middle. This is about 600 miles across, and according to Olkin could be the result of internal processing. That’s right, active geology.
Just as with similar details on Pluto, the team’s speculations about what is causing this geology are so far guarded and vague.
But what’s certain is that “something is making these two worlds very, very different,” says Alan Stern, the mission’s principal investigator. Pluto is covered in water ice, Charon has massive cliffs. But the shroud of mystery that covers both is being steadily removed.
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Okay, here’s the one you’ve been waiting for: Here is the first true close-up picture of Pluto’s surface, focused on the edge of the southeastern hemisphere. It shows that Pluto has mountains, and that those mountains are made of water ice. And most exciting of all—those mountains might be geologically active.
“The most striking geology is that we haven’t found a single impact crater,” says John Spencer, one of New Horizons’ lead scientists. “That means this is a very young surface.” “Young” being less than 100 million years old.
So what could be driving that geologic activity? There’s no planetary body large enough to be driving tidal energy, so Spencer speculates that the energy could be driven by latent radioactive energy, or a large interior ocean could release energy as it freezes. Or, the planet could be storing energy from its formation through some other, unknown process.
And yeah, about that water. See those mountains? Those are about 11,000 feet tall. Frozen nitrogen and methane would crumble under their own weight at those elevations. And because of Pluto’s mass and size, they can’t be bedrock. The only way to balance that equation is ice.
Stay tuned for more science, more pictures, and more excitement from the Pluto system.
Zoom into Pluto & discover mountains, seen during yesterday’s @NASANewHorizons #PlutoFlyby: http://t.co/6QLXLxiW0o https://t.co/toJQ0j7wB6
— NASA (@NASA) July 15, 2015
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In Greek mythology, the hydra was a many-headed dragon snake with regeneration powers. That’s impressive, but I’m pretty sure that its namesake moon has officially eclipsed its forbearer.
“Pluto and Charon are going to steal the day today, but let’s not forget that Pluto has four small moons as well that we want to collect data on,” says New Horizons project scientist Hal Weaver. “This morning, we got the first really well-resolved images of Hydra.”
Prior to this image, the best pictures of Hydra looked like someone took a quick pass of an eraser over a pencil-drawn period. By comparison, each pixel in the relatively crisp little nugget above represents two miles.
The cool thing about Hydra is how much we have to learn about it. Before today, Hydra was square. Now we can finally see its shape, a wobbly sort of potato-looking thing. We also know its size: 28 by 19 miles across. “New Horizons makes it easy for us,” says Weaver. “Just count the number of pixels across.”
And there’s plenty more to come.
As New Horizons floods its team with data, they will learn more about its composition and will develop clues about its origins. Combined with data from the other four moons and Pluto itself, that data will help scientists pull together an origin story for the tiny planetary system.
So, apologies to the lord of the underworld, his ferryman, his ferryman’s mom, pet dog, and many-headed snake monster, your myths are no match for reality.
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It is less than three hours until New Horizons’ safe and sound message arrives—or doesn’t. Worrier that I am, I’m still worried that the brave little probe might run afoul of a dastardly space pebble. But there’s something else that’s also been nagging me: What if Pluto suddenly disappeared?
It’s a question with long odds—much more improbable than the 1 in 5,000 chance of collision Alan Stern mentioned this morning—and let’s face it, pretty silly. But I still found some experts to scratch my itch.
Specifically, I’m curious about the gravitational effects. Would we feel it on Earth? “If Pluto disappeared, it certainly wouldn’t have an effect on Earth,” says Sarah Hörst, a planetary scientist at Johns Hopkins University. Gravity depends on mass, and the force it exerts decreases over distance. Pluto is too tiny, and too far, to affect Earth. And Mars. And Jupiter. And Saturn, Uranus, and Neptune.
Pluto is so tiny compared to everything else that pretty much only its moons would notice if it disappeared. “Notice” meaning they’d shoot off into space.
In fact, even New Horizons wouldn’t really be affected. “There’s no magnetometer, and we’re not using any forces around the planet to trigger anything on board,” says Alice Bowman, New Horizons’ mission operations manager.
New Horizons’ flyby maneuvers are pre-programmed, so if Pluto suddenly disappeared all it would return are pictures of empty space. And because the light from Pluto would disappear before New Horizons had sent its 4:27pm ET message home, any Earthly telescopes would get the news first.
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The Charon name thing is starting to get to me. Every meeting, press brief, interview I hear the name of Pluto’s largest moon pronounced differently. I swear to Hades, sometimes I hear the same person pronounce it two ways. Granted, I’m jet lagged, sleep deprived, and the coffee in the press room is lukewarm and from Dunkin’ Donuts (what gives, NASA?), but I’m starting to feel like someone is messing with me.
So I started asking people—mostly people wearing black polos emblazoned with the nine-sided New Horizons logo: “How do you pronounce the name of Pluto’s largest moon?” I didn’t get far enough to get meaningful survey results, but I did find out why the results would always be mixed.
That’s because I ran into Will Grundy, one of New Horizons’ co-investigators and an astronomer at Lowell Observatory. “Well, the original Greek way to pronounce it would be Gheghron,” he says, shoving the word out of the back of his throat like it’s a big, fat Klingon loogie. Gross, but makes sense. After all, Charon was the ferryman who brought damned souls across the river Styx into Pluto’s realm. But the astronomer who gave the moon its name didn’t even know about the Greek myth when he picked the name1.
Jim Christy, who discovered the moon in 1978, had promised his wife Charlene he would name the object after her. See, his wife’s name is Charlene, so he took her nickname—Char—and threw an -on in on the end to science things up.
Some of his colleagues had been lobbying to name the moon Persephone (Pluto the god’s abducted queen), so he started doing some research. That’s when he stumbled across the Greek myth, and with that argument in hand the astronomical community informally adopted Charon later that year, and then formally in 1985.
So what’s that got to do with the pronunciation? Most astronomers, says Grundy, pronounce it “Share-on, as a tip of the hat to Jim and his wife.” But then he shrugs and says everybody flops back and forth all the time. “We all say it both ways in a single sentence.”
Really? Guys, that is a hell of a way to come up with nomenclature. Lunacy, even.
1 Update 14:26 ET July 20 2015. This Sky & Telescope article from 2008 has the entire naming episode in full detail.
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What we have so far:
Kar-on
Kare-on
Shar-on
Share-on
Sauron
Cuarón
Sharon
Sharona
Jiff
Your thoughts?
(Thanks for the punchline, Paul Sabourin.)
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Once you have pictures of a never-before-seen-up-close almost-planet, you have to start naming what you see. And according to an image of from the New Horizons press room that our correspondent Nick Stockton tweeted earlier today, the Plutonians have started naming their surroundings…informally.
The names are all related to various mythologies of the underworld, appropriately enough. They also suggest that some of these researchers are pretty darn nerdy—though some of the names seem to have come from votes people submitted online during New Horizons’ flight.
Like, for example, “Cthulu,” the name of an elder god from the fiction of HP Lovecraft. Or what about “Balrog,” the name of the monster that seemingly killed Gandalf the Grey in the Lord of the Rings trilogy? Meng-p’o is the Buddhist goddess of forgetfulness and amnesia—she lives in the underworld. Hun-Came and Vucub-Came are Mayan death gods.
We thought at first that Krun was a reference to a Non-Player Character from the hellfire peninsula in World of Worldcraft, but he’s actually one of five lords of the underworld for the Mandaeans, an ancient religion from the Iraq-Iran region. (His nickname is “Mountain-of-Flesh.”) Ala is an underworld and harvest goddess of the Ibo people of eastern Nigeria.
Pluto might not technically be a planet, but it has some great place-names.
Sorry for potato quality but here are informal names new horizons team has given Pluto’s features #PlutoFlyby pic.twitter.com/y5pNYMFuP6
— Nick Stockton (@StocktonSays) July 14, 2015
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NASA/JHUAPL/SWRI
Holy moly what a press conference we just had here at Pluto central. Alan Stern unleashed his science officers with new images and new science, and the first to drop were the highest resolution color pics of Pluto and Charon yet.
Each shows some pretty cool stuff. For Pluto, the biggest revelation is that the big heart is actually two different colors. Those colors (exaggerated for contrast) indicate different geologic, tectonic, or morphologic origins. And the rest of the visible world is a mosaic of patina. “Some regions are relatively ancient, and other places are very young and currently undergoing geologic evolution,” said Jeff Moore, the New Horizons team scientist from NASA Ames who presented the images.
But characteristic of the New Horizons team, Moore was guarded on the details. He said he’s waiting for stereographic data—which will show relief—before speculating any further on what might be happening on the dwarf planet’s surface. For instance, the heart’s left lobe currently looks as smooth as a cherub’s cheek, but some cratering might show up at higher resolutions.
The information from Charon is probably even more surprising. See that big blob of red? That stuff came from Pluto. “Charon does not have an atmosphere that is known so far,” says Will Grundy, a New Horizons team scientist and astronomer at Lowell Observatory. Charon may not have an atmosphere, but Pluto is leaking nitrogen like crazy. And as those nitrogen particles leave Pluto, Grundy says they could be getting dragged into Charon’s gravity. The distribution over the moon would be about even. But while nitrogen particles will burn away on the always-sunny equatorial and midlatitude regions, those that land on the polar night side are in the dark for decades.
If this hypothesis is correct, the chemical processes in the nitrogen would stain the und