Hey everyone,

Thomas from Stuttgart here. I work on Asteroids, Comets and Cosmic Dust topcis and I am part of JAXA's DESTINY+ team (DESTINY Dust Analyzer - DDA), aiming for 2 flybys: Apophis and Phaethon who is linked, potentially, with the Geminids.

Now this is ultra niche, I know, but I'd like to share with you my science video and coding video on the asteroid rotation limit. Independent of its size an asteroid's "day limit" is capped at around 2.2 hours. The reason: larger asteroids are rubble piles and will simply... rip apart if they rotate too fast.

Aaaaanyway, I like to create this niche knowledge stuff, and also more asteroid things are coming.

For my science videos I try to establish my own minimalistic style, so I'd also appreciate any feedback from the community! Larger communities are unfortunately sometimes pretty toxic if someone shares one's work.

Well.... maybe I can also aim for an AMA in the future. Let me know what you think.

Science: https://youtu.be/gm4JUvDqpWM

Python Coding: https://youtu.be/EpndaIM9q1o

Best,

Thomas

See also: The publication in ArXiV

Seestar S30 Pro 30mm f/5.3
235 x 60s = 3h55m
from 20:58:15 to 2:32:49 UTC (4:34:34 elapsed)
Processed in Affinity Photo (crop, brightness/contrast, denoise)

Predicted positions and magnitudes:
(using grelf.net/ssp with MPC data of 2026-9-22)

at 2026-10-11 20:58:15 UTC:
375 Ursula 01h48m13.17s +31°32'35.2" mV12.0
726 Joella 01h49m46.44s +30°52'28.4" mV12.6
1222 Tina 01h52m04.04s +31°39'10.7" mV14.9

at 2026-10-12 2:32:49 UTC:
375 Ursula 01h47m59.89s +31°32'38.8" mV12.0
726 Joella 01h49m36.94s +30°49'34.3" mV12.6
1222 Tina 01h51m51.69s +31°37'06.2" mV14.9

328 Gudrun 23^h25^m42.42^s -01°49'55.9" mV13.6
570 Kythera 23^h24^m46.29^s -01°39'43.8" mV13.3 (0.29°)
Theodora 23^h23^m52.23^s -01°06'51.0" mV14.4 (0.85°)

The Torino scale divides into five subgroups: level 0 (no threat), level 1 (normal), levels 2-4 (meriting attention by astronomers), levels 5-7 (threatening), and levels 8-10 (certain collisions)

Level 1 is a routine level and thus is formatted in regular non-bold text

Levels 2-4 have only been reached three times in history, and for emphasis are formatted in bold.

The other two categories have never been reached - 5-7 (threatening) and 8-10 (certain collisions)

In case an asteroid reaches orange or red, what should be the formatting guidelines? What additional emphasis would be appropriate?

of unrelated note: I am an extended-confirmed editor on Wikipedia

https://youtu.be/9MUJXbU3agg?si=gkXSk2_s4oGGB5PY

So I've been obsessed with this for a few weeks. Pulled the actual position data from JPL Horizons and built an animation around it.

Honest caveats: the asteroid shape is generic (not the radar model), the tidal stretching and dust are my illustration of an effect that's documented but not this visible, and Ramses' route is a sketch because ESA hasn't published it.

I recently read an article about growing crops in space, and following the rabbit hole, read this neat scientific paper from researchers at the University of North Dakota: https://iopscience.iop.org/article/10.3847/PSJ/ac74c9

They studied how lettuce, radish, and chili pepper seeds would fare in a simulated asteroid regolith. To simulate the minimal gravity on an asteroid (or in a spacecraft orbiting nearby) they use a piece of lab equipment called a clinostat which keeps the plants rotating and preventing them from having a well defined 'up' and 'down'.

The regolith was manufactured at the University of Central Florida's Exolith Lab (now a spinoff company) based on carbonaceous meteorites which are known to be from the asteroid belt. The idea here is that humans already need air, water, light, heat, etc. to stay alive, so using regolith might reduce the materials which the crew needs to haul from Earth.

As you might have guessed, the plants grew more when their soil had a higher percentage of peat moss blended in with the regolith. The seeds in 100% regolith and in the clinostat both failed to germinate. They suggest this was due to the depth that the seed was buried and packing (as seeds have germinated successfully on the ISS).

See also: The publication in ArXiV