My latest 3D artwork "Monsieur M. And His Lilies" has been featured in this week's Best of Blender: https://www.blendernation.com/2026/08/07/best-of-blender-artists-2026-32/

My updated class THE SCIENCE OF THE SOLAR SYSTEM is now LIVE and COMPLETELY FREE at www.coursera.com/learn/solar-system

27 hours of lectures, full quizzes, full exam. And free. You can’t even pay if you want to. Or you can just find the lectures on YouTube any time.

First multi-opposition recoveries of large-orbit LSST TNOs

Chantal Hemmann, Brett Gladman, Justine Obidowski, Jean-Marc Petit, JJ Kavelaars
https://arxiv.org/abs/2608.04287 https://arxiv.org/pdf/2608.04287 https://arxiv.org/html/2608.04287

arXiv:2608.04287v1 Announce Type: new
Abstract: We report 2026 CFHT second-opposition recovery observations of three large-orbit Trans-Neptunian Objects (TNOs) discovered by the Vera C. Rubin Telescope's Legacy Survey of Space and Time (LSST) during preliminary observations in 2025. Due to their potential scientific interest, we selected three TNOs whose nominal semimajor axis could be larger than 100~au according to their short-arc ($\leq0.2$-yr) LSST observations. These three targets (2025 LS2, 2025 ME278, 2025 MX348) had discovery opposition orbits of varying observation quality (in terms of the duration and distribution of observations). In two cases, the 2026 CFHT recoveries showed that the semimajor axis dropped by a factor of $\simeq$3-10, and that the object appears to be a (common) plutino in the 3:2 mean-motion resonance with Neptune. We discuss how and why the estimated orbital elements evolved, and re-caution the community to be skeptical of unusual TNO orbits until they have multi-opposition recoveries.

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☀️🌑🌍 Just 6 days until the next total #solareclipse! Download my free, ad-free, and add-on-free "Solar Eclipse Live" app for iOS. It uses the #opensource tools REBOUND and ASSIST to calculate accurate ephemeris data on the fly without the need for an internet connection. So it's great if you plan to chase the totality in the middle of nowhere. And yeah, you really want to see totality if you can, as proven by this xkcd comic.

https://apps.apple.com/us/app/solar-eclipse-live/id6480014046

https://xkcd.com/2914/

From last December: a new iteration on the #JezeroBrightRocks studies (previously https://mastodon.social/@sharponlooker/114042437186059919), this time with comparison to Earth's analogs. It still doesn't extend beyond sol 1000 (Neretva Vallis) so it doesn't cover the CRISM detections around Pico Turquino/Seattle Park (fig. 7)

Broz et al: "Alteration history of aluminum-rich rocks at Jezero crater"
https://doi.org/10.1038/s43247-025-02856-3

#JezeroDeltaScience #JezeroRimScience #kaolinite

Some favorite pictures from Harrison Schmitt’s visit today. See alt text for details!

Today's evening run, adorned by a quiet #ÅnLagan and a scenic sundown.

#Småland

@FaithfullJohn multiple references to Stac Fada as a potential terrestrial analog in the paper 😉

https://mastodon.scot/@FaithfullJohn/116334361431993618

If... 😢

All the complexity of the #JezeroCrater outer rim on display 😍

Jones et al: "Stratigraphy Preserved on the Jezero Crater Rim Reveals Repeated Impacts on Early Mars"
https://doi.org/10.1029/2026JE009779

#JezeroRimScience #JezeroRimSpherules

Total solar #eclipse loading ☀️🌕🌍

On 12 August, the #Moon will slip between the #Earth and the #Sun, turning day into night for up to a minute and a half along the path of totality.

Get the gist with ESO fellow Mar Carretero Castrillo 🎬👇

1/4

#astrodon #astronomy #astrophysics #space #science #solareclipse

Broken heart 💔

#freeAssociation

Processed, night-time SHERLOC_WATSON image captured under artificial light
looking down (-82°) from RMC 90.0000
Sol 1937, LMST: 22:50:46
Original: https://mars.nasa.gov/mars2020-raw-images/pub/ods/surface/sol/01937/ids/edr/browse/shrlc/SIF_1937_0838934950_656EBY_N0900000SRLC08061_0000LMJ01.png

Credit: #NASA #JPL-Caltech/65dBnoise

#Perseverance #Mars2020 #Solarocks #Space

«Interview with a Sysadmin in 2026 [Corporate]» Este tipo es un genio haciendo vídeos, un poquito de nicho, pero yo me parto de la risa https://youtube.com/watch?v=I7IHInNJZvE

#SilentSunday #LakeLife
(pontoon boats reputedly invented in #Minnesota)

¿Alguien recuerda a Atahualpa Yupanqui ¿Y a Mercedes Sosa? Pa' mí son muy buena gente que me ha enseñado mucho desde mi más tierna infancia. Y esta canción debería ser el himno del Fediverso, he dicho. Solo haría falta cambiar "tantos hermanos" por "tantes hermanes" y poco más.
Les dejo la letra completa en el ALT.

"Nytt cafebiträde" 🙃

#SilentSunday

And transonic is particularly useful in tunnels, as that's where the Navier Stokes equation gets real chaotic and the adaptive time step in your CFD starts to get real short.

That's why most airliners look alike, they can take advantage of decades of transonic research in the common shape.

Rotation and Mutual Eclipse Events Season in the Kuiper Belt: (524366) 2001 XR$_{254}$

Audrey Thirouin, William M. Grundy, Scott S. Sheppard, Keith S. Noll, Jos\'e Mar\'ia G\'omez-Lim\'on, Benjamin Proudfoot
https://arxiv.org/abs/2607.27589 https://arxiv.org/pdf/2607.27589 https://arxiv.org/html/2607.27589

arXiv:2607.27589v1 Announce Type: new
Abstract: (524366) 2001 XR$_{254}$ is a dynamically Cold Classical Kuiper Belt Object that is a nearly equal-sized wide binary whose upcoming mutual events season makes it a particularly valuable target for physical characterization. In advance of the mutual eclipse events, we conducted a ground-based photometric observing campaign between 2021 and 2026 using the \textit{Lowell Discovery Telescope} to investigate the rotational and physical properties of the system, to refine predictions for its future mutual events, as well as provide a lightcurve we can use as a baseline to identify eclipse events superimposed with the rotation. We derive a double-peaked asymmetric rotational lightcurve with a period of 11.17$\pm$0.04 h and a lightcurve amplitude of 0.42$\pm$0.04 mag. The lightcurve presents a sharp V-shaped minimum consistent with the primary being a close/contact binary, possibly making this a triple system. Using the Keplerian mutual orbit solution, we model the upcoming mutual event season expected between $\sim$2031 and $\sim$2040 and present some individual events for future campaigns. 2001 XR$_{254}$ is one of the few wide binary Kuiper belt systems with a well-determined mutual orbit and a soon observable mutual eclipse event season. Mutual event observations of this possible triple system will provide a rare opportunity to improve component sizes, shapes, densities, and surface properties, offering insights into the formation of the Kuiper Belt.

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Malmö yesterday evening

#Skåne #onlookerOnTour

Tried a new hotel and were upgraded so high up, you could see me & Mrs Wife's common former workplaces all from one window, and even our old hamlet 😍

#onlookerOnTour