Pluto's recent results I hung out with Pluto's scientists for the dwarf planet's 10th anniversary

Last week's conference on the 10th anniversary of New Horizons' Pluto flyby was...well...out of this world!

Read my newsletter for details.

#Pluto10

New Horizons: Celebrating a decade since the Pluto flyby New Horizons Principal Investigator Alan Stern joins us to celebrate the Pluto flyby’s 10th anniversary, with updates from planetary scientist Adeene…

I chatted with @planetarysociety.bsky.social to celebrate the 10-year anniversary of New Horizons' Pluto flyby, #Pluto10, and the profound joy of science that can be done on some of the farthest bodies in our Solar System: www.planetary.org/planetary-ra...

A photograph of a sketch in my notebook where I summarize a talk by Alan Stern and Orkan Umurhan. on the left is a sketch of Pluto centered on Sputnik Planitia. I highlight the northern part of Sputnik Benicia, where there are some darkened streaks amongst the convective swirls of the glacier. On the right hand side of the sketch, I zoom in to a cross-section of this portion of the glacier. In the side profile, you can see a thick, nitrogen ice glacier, shown mostly in grays, overlying a water-rich icy crust, shown in red. They hypothesis that the bottom of the glacier is melting, producing effectively liquid nitrogen. Unlike basal melt in a terrestrial glacier (water) which stays confined to the bottom of the glacier, basal melt in a nitrogen ice glacier would be buoyant and rise through the glacier to the surface. I show that here with some blue coloring: I show a layer of blue at the bottom of the glacier, and then a upwelling that goes towards the surface. At the surface of the cross-section, I show the surface of Sputnik, including a convective cell that is bordered by a trough. The upwelling melt reaches the surface first at the trough, fills in the topographic low, and darken it. in a text box to the side, I explain their hypothesis. They believe that this region of Sputnik is sublimating away. As the glacier thins, it reduces stress on the ice, promoting the growth of larger grain sizes. Larger green sizes, inhibit convection, and make it harder for the glacier to lose heat. Thus the bottom of the glacier can get warmer and melt.

Alan Stern & Orkan Umurhan—there are unusual dark streaks and swirls in the northern part of Sputnik Planitia (the giant nitrogen-ice glacier that makes up part of Pluto’s heart). They propose that this is the consequence of melt (liquid nitrogen) rising from the base of the glacier! #Pluto10

A photograph of a sketch in my notebook, done for the T +10 years Pluto workshop that was held last week at APL. The sketch shows the number 10 drawn out in a very modern font. At the top of the one is the new horizon spacecraft, glistening in gold. The number one is almost a trail left behind the spacecraft, drawn in a blue gradient. Inside of the zero is a sketch of Pluto itself, centered on the encounter hemisphere, and Sputnik Planitia. Pluto is in shades of red, brown, yellow, and gray. Beneath the large number 10 is the title of the conference, “progress and understanding the Pluto system: 10 years after flyby.“ I’ve also drawn some colorful rainbow “swooshes” behind the graphics. The entire drawing is maybe 6 inches across, as you can see the pen just next to the notebook for scale.

10 years ago, the New Horizons mission flew past Pluto. That world, that mission, and the team of people that made it happen—changed my life.

Last week was the #Pluto10 workshop. It was amazing to see all of the continuing science from Pluto!

That's a wrap! Stern is thanking everyone who helped put #Pluto10 together.

"I don't know the next time we'll have over a hundred scientists come together to talk about Pluto."

See y'all at Pluto15!! <I have hope>

Holler: "Can I throw out one of three points? I think that's a philosophical question."

#Pluto10

Holler: Images from JWST were focused on Pluto. "Nix and Hydra end up as bonus science." They weren't expected to be there & observable. Nothing from Styx & Kerberos, which are too faint.

#Pluto10

Holler hits that conference end-of-week feeling perfectly.

"If you feel like you have a smoothie between your ears."

Yup.

#Pluto10

Holler: Nix appears to be pretty close to solar color.

#Pluto10

Brian Holler is giving the last talk of the conference, The Unique Surface Compositions of Pluto's Minor Satellites Nix and Hydra.

Work features a high school student, Derek Wang.

#Pluto10

"A lot of what I'm presenting is based on his initial analysis."

Porter: The general trend of the dust in the system is to drift inwards. It could be that Nix is somewhat contaminated with Hydra dust.

#Pluto10

Porter: New HST observations from April-June 2025. "We got Starlinked."

>.<

#Pluto10

Porter: Densities for Nix and Hydra both were ~1.1 g/cm^3. "You can't just make these out of pure ice. They have to have some rocky component to them."

#Pluto10

Porter: Astrometry data from HST goes from 2006-2019. Hyper precision around flyby in 2015. Combine the two data sets in a single fit.

#Pluto10

Porter: "We expect all of these are experiencing some sort of pole variation over time." They're spinning fast enough that they're not chaotic, just precessing. It's been enough time since the flyby that photometry should show differences.

#Pluto10

Porter" Hydra's shape model "would be baffling if you didn't see the shape." Then he adds, "We see the shape and it's still baffling."

#Pluto10

Porter: There is a lot of data from Nix and Hydra because both were discovered before we wrote the New Horizons observation sequence.

#Pluto10

Porter: I'll talk about shape, mass and densities. We can't do that with NH alone but we can use NH maximally.

#Pluto10

Simon Porter on the Shapes, Masses, and Densities of the Small Satellites of Pluto

#Pluto10

"This is going to be kind of a grab bag talk."

Denton's video of kiss-and-capture for Pluto. Starring proto-Vin Diesel.

#Pluto10

Kenyon: Looking at the moons, stable orbits around Pluto, our goal is to understand stability over 4.5 Gyr.

#Pluto10

Scott Kenyon joins us remotely with Formation and Stability of the Pluto-Charon Small Satellite System

#Pluto10

Last break of #Pluto10

Back at 10:50!

McKinnon says he and Schenk, as a thought experiment, looked for clues of a collision on the surface of Pluto. Schenk is working on updating the entire STEREO map of Pluto with 5600 control points "and counting." That's double the original STEREO map.

#Pluto10

Bill McKinnon is asking the question, Is There Geological, Geophysical, or Geochemical Evidence for the Charon-Forming Impact?

#Pluto10

Denton: Kiss-and-capture can feasibly reproduce the smaller Orcus-Vanth system. That suggests this may work in the rest of the solar system. With the caveat that the OV system's smaller mass relates to its material strength.

#Pluto10

Denton: If Pluto had an ocean, kiss-and-capture won't work. They merge and create "this weird snowman, super-Arrokath-looking thing."

#Pluto10

You'll have to ask @spacewhalerider.com for a picture

By the way, today is @spacewhalerider.com 's birthday!!

"I've always wanted to talk for 45 mts on my bday!" :)

I couldn't find a happy birthday image with an actual whale in space, and I'm too lazy to make one, so I just found a nice happy space whale.

#Pluto10

Here is @spacewhalerider.com kiss-capture model in video form

#Pluto10

www.youtube.com/watch?v=HMrS...

Denton: Charon grazed Pluto at an oblique angle, grazing it just enough to get caught, shear, and snap away. If it is less, the two bodies merge because they lack geostrength.

#Pluto10