Pluto's Heart

November 16, 2016 9:08 PM

"Binzel suspects that Pluto’s “heart,” particularly its left ventricle region, called Sputnik Planitia, was created by an impact with another object in the Kuiper belt, an asteroid belt near the edge of the solar system. That impact gouged out a piece of the surface of Pluto, making the crust very thin at the point of impact. Underground water, kept warm by Pluto’s radioactivity, then flooded this area of thin crust like water in a blister. This formed the extra mass that caused Pluto to reorient itself so the impact zone faced away from Charon."

"Both teams found that the strange alignment with Charon could be best explained if Sputnik Planitia is much more massive than surrounding regions on Pluto. Over millions of years, this “positive mass anomaly” caused the entire planet to tilt askew into its present alignment with Charon, similar to how a Frisbee with coins taped to one edge will tumble over instead of smoothly spinning."

Reorientation of Sputnik Planitia implies a subsurface ocean on Pluto (nature.com)

"The cracks and faults on Pluto’s surface tell the story of its rollover, according to two new studies published today in Nature."

Realistic flyby animation

Final data received from New Horizons. More. Even more, at less than 2400 baud.

Pluto and Charon plushies.

posted by Eyebrows McGee (22 comments total)

Those high-resolution photos still give slight goosebumps every time I see them.
posted by Harald74 at 4:49 AM on November 17, 2016 [2 favorites]

I just figured that Pluto keeps its secret true face away from us so it will be a surprise in the End Times.
posted by GenjiandProust at 5:01 AM on November 17, 2016 [2 favorites]

One competing theory is that Charon is an artificial world housing a mass relay left by an alien benefactor race, and Pluto bears the scars of their advanced matter manipulation.
posted by Mr.Encyclopedia at 5:45 AM on November 17, 2016 [10 favorites]

I thought the New York Times' coverage did a great job of putting a human face on this scientific research.
posted by Horace Rumpole at 6:22 AM on November 17, 2016 [3 favorites]

I went looking for the Hubble Telescope images of Pluto, and came to wonder how much better the James Webb Telescope images will look (after launch in late 2018, that is).
posted by Harald74 at 6:27 AM on November 17, 2016

Nice try astronomers, but Plutos heart was broken when you spurned it, obvs.
posted by rodlymight at 7:15 AM on November 17, 2016 [9 favorites]

We need an orbiter around Pluto. Yeah, I said need and I will glare vigorously at anyone who disagrees.

However, if an orbiter was launched today, it would still be about 30 years before it reached Pluto. And planning these missions takes around a decade, so...enjoy those those high resolution photos from a few hundred miles above Pluto future reader!

Really fascinating how water and underground oceans are being discovered throughout our solar system, makes me happy and hopeful. Then I turn on the news.
posted by Brandon Blatcher at 7:41 AM on November 17, 2016 [7 favorites]

it's the plutonians mining the core to power their diamond cars and golden showers
posted by ryanrs at 7:44 AM on November 17, 2016 [3 favorites]

and golden showers

:-o
posted by col_pogo at 8:31 AM on November 17, 2016

The problem with orbiting Pluto is that you want to be moving fast to get there in a reasonable number of years but need to dump most of your relative velocity to get into orbit. New Horizons is moving *fast* -- it flew past Pluto at over 13,700 m/s and would need to slow down to about 1,200 m/s just to get into orbit. (To put this in human terms, a New Horizons fly-by of the United States would be over in less than five minutes.)
posted by nathan_teske at 10:03 AM on November 17, 2016

if you would like a closer look
just hop into this brain cylinder
here is a saw
get to work
of course i am serious
i am your friend
your ami-go
dont just sit here listening to your
robert smith albums
i will make sure you have a good time
in the brain cylinder
i am a
fun guy
you goth
get sawin
posted by robocop is bleeding at 11:18 AM on November 17, 2016 [7 favorites]

The problem with orbiting Pluto is that you want to be moving fast to get there in a reasonable number of years but need to dump most of your relative velocity to get into orbit

The problem is defining "reasonable number of years". Yes, New Horizons was catapulted there so that it would reach the planet (#notadwarfplanetneverforget) before the lead investigator got too old. Understandable, but it does point out a weakness in space exploration, that of too short human lives. Hopefully a Pluto orbiter would have an infrastructure that grooms investigators to pass on the project down the line.
posted by Brandon Blatcher at 11:23 AM on November 17, 2016

I thought the New York Times' coverage did a great job of putting a human face on this scientific research.

Pluto has internal organs and a human face?? Oh my
posted by prize bull octorok at 11:28 AM on November 17, 2016 [1 favorite]

On the flip side, a 100 year mission with ten gravity assists that enters Pluto's gravitational influence with a tolerable eccentricity risks hardware failure through sheer aging issues. Yeah, the researchers are frail bags of mostly water, but I'd hate to think of the challenges of engineering even a 50 year probe at this point.

I mean, yes yes, Voyager is expected to be _just barely_ working on its 50th birthday and we've had 40 years of knowledge to build upon, but still. Oof. And then there's the budgetary question - who pays for all those years of monitoring and maintenance?
posted by Kyol at 12:25 PM on November 17, 2016

Put it on my tab, I'm good for it!
posted by Brandon Blatcher at 12:29 PM on November 17, 2016 [1 favorite]

OMG Harald74, the Hubble image of Pluto you linked has the same orientation as the high-res one in the Vox article. It really brings the difference home.
posted by Joe in Australia at 2:41 PM on November 17, 2016 [2 favorites]

> Put it on my tab, I'm good for it!

We're going to need a substantial deposit, plus a credit card for incidentals.
posted by Sunburnt at 2:47 PM on November 17, 2016

From the Atlantic piece:

Pluto and its moon, Charon, always show the same face to one another, the way the moon is locked in the same direction toward Earth. The bright Tombaugh Regio area always faces away from Charon. The alignment is so precise that it’s as if Charon floats over the area directly opposite Sputnik Planitia. This suggests there’s extra mass in Sputnik Planitia, and it forced Pluto to roll over to balance itself between its own mass and that of its sister moon. Astronomers spell out how this reorganization happened in a pair of papers published today in Nature.

It's interesting to contrast this with the situation of the Earth and the Moon, in which the more massive side of the Moon always points toward the Earth:

The forces that caused tidal locking resulted in a farside crust almost twice as thick as on the nearside, and the Moon's center of mass was displaced toward the Earth and away from the Moon's center of figure by 1.982 kilometers. The orientation of the Moon with respect to the Earth may be partly due to the distribution of dense lavas in the low-lying basins of the nearside which cause the heavier side of the Moon to always face the Earth (Melosh 2011, p34).

I don't immediately see the reason for the difference, though the Earth is not tidally locked to the Moon the way Pluto is locked to Charon, but I don't think that should matter.
posted by jamjam at 2:48 PM on November 17, 2016

My understanding is a tidal pull can result in one or the other and it is mostly random chance whether the heavy side points in or out because generally there isn't enough centripetal force relative to the tidal force to preferentially move the heavy side out.
posted by Mitheral at 4:37 PM on November 17, 2016 [1 favorite]

It still is special to me that we are the first humans in the history of the world to know what Pluto looks like.
posted by Sreiny at 5:26 PM on November 17, 2016 [1 favorite]

I think you must be right, Mitheral; something along the lines of: the more dominant gravitational forces are for any given moon or planet, the more likely (depending on initial conditions) a tide-locked heavy side of that body will end up, after a dissipative process, pointing toward its companion and the more stable that configuration will be; and the more dominant centripetal forces are, the more likely that a tide-locked heavy side will end up pointing outward, and the more stable that configuration will be -- perhaps.
posted by jamjam at 8:28 PM on November 17, 2016

a 100 year mission with ten gravity assists that enters Pluto's gravitational influence with a tolerable eccentricity risks hardware failure through sheer aging issues

Not to mention the half-life of Pu-238, which is what powers these sort of spacecraft, is 88 years.
posted by ryanrs at 2:54 AM on November 18, 2016