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#asteroid

12 posts3 participants0 posts today
Public
Matteo Ceriotti

Edward Tomanek-Volynets' #PhD #research has just been published:

"The pointer network for reward maximisation in multi-target
space mission sequence selection"

This work uses machine learning to optimise sequences of targets to visit in a multi-target #space mission, for example #asteroid rendezvous, #spacedebris removal, or #satellite servicing.

#free #OpenAccess:
doi.org/10.1016/j.asr.2025.04.

Congrats Edward! 🎓

Multi-target space mission scenarios such as asteroid rendezvous, debris removal or satellite servicing, require targeting several orbits in a single mission, often to be selected among a large set, and therefore choosing optimal sequences of these orbits to be visited. This paper demonstrates a reinforcement-learning-based framework for selecting the sequence of targets to be visited in large-scale multitarget mission optimisation problems. The sequence selection is a NP-hard combinatorial optimisation problem. The proposed method builds upon a neural network architecture for combinatorial optimisation originally developed for Euclidean problems, to produce estimates of the optimal sequence of targets in very short amounts of time. The neural network is trained using a policy-gradient reinforcement-learning approach. Once training is complete, the network can be evaluated in two ways: one of these (greedy decoding) produces solutions on average 15% less optimal than Ant Colony Optimisation (ACO); the other (stochastic search) is on average 5% less optimal than ACO, using an iterative process that is slower than greedy decoding but still orders of magnitude faster than ACO. The quality of the network’s solutions is shown both averaged over large amounts of problems, and demonstrated more closely on a few specific instances.
#ML#AI#engineering
Public
Olly 👾

NASA doubles odds of Moon hitting Near-Earth Asteroid [2024 YR4].

"Experts at NASA’s Center for Near Earth Object Studies at the agency’s Jet Propulsion Laboratory have updated [2024 YR4]’s chance of impacting the Moon on December 22, 2032 from 1.7 to 3.8 percent," the agency said.

science.nasa.gov/blogs/planeta

GIF
#asteroid#2024yr4#space
Public
Spaceflight 🚀

@planet4589 : "When I was a kid 🧒, it was #LEO. Now, the frontier is out near the #asteroid belt, and the #Moon and #Mars are becoming part of where humanity just hangs out, maybe not yet as people, but with #robots. Meanwhile, #LEO is so normalized that it doesn’t take a #SpaceAgency to deal with it. You just call #SpaceX. Thousand years from now, perhaps more people live off Earth 🌌 than on it" cearkadia.edu.pl/jonathan-mcdo

cearkadia · Jonathan McDowell on Retiring From Harvard and Leaving the U.S. - cearkadiaJonathan McDowell is a go-to expert for all things spaceflight. Thousands of subscribers read his monthly Space Report, and far more people have seen him
#SpaceExploration#SpaceHistory
Public *
IOTA European Section

Shadow profile of slow-rotating asteroid (144) Vibilia measured by 6 stations in Poland and Germany on 2025 April 4. One additional observer reported a negative observation from the northern edge of the shadow.

cloud.occultwatcher.net/event/

The team of SODIS has calculated a preliminary profile of the asteroid of 134 x 134 km.

The dashed line shows the predicted centre line of the shadow. Another very accurate prediction.

Shadow profile of asteroid (144) Vibilia measured during a stellar occultation on 2025 April 4 in Germany and Poland. The dashed chord no. 5 shows the predicted centre line.
#astronomy#occultation#citizenscience
Public
Lukas VFN 🇪🇺

Life recovered rapidly at site of dino-killing asteroid. A hydrothermal system may have helped
phys.org/news/2025-04-life-rec paper: nature.com/articles/s41467-025

"the crater it left behind in the #GulfOfMexico was a literal hotbed for life, enriching the overlying #ocean for at least 700,000 years... a #hydrothermal system created by the #asteroid impact may have helped marine life flourish at the impact site by generating and circulating nutrients in the crater environment."

Simplified map of the Gulf of Mexico just after the asteroid impact.
Public
NewsFlash

✅ Importance Score: 45 / 100

Study: Dinosaur Extinction Debate Reignited by Fossil Availability
A recent study suggests that dinosaurs were likely not in decline before a m...
More » newsflash.one/2025/04/08/rethi

News FlashRethink of fossils hints dinosaurs still thrived before asteroid hit
More from NewsFlash
#News#BreakingNews#LatestNews
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