2024-10-13 More backlog, up to tri-axial Mars)

Between one thing and another (which includes my laptop deciding to power-down half-way through an OS upgrade), a week of inactivity. Fortunately, nowt published, so let's see what is in the pile.

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Bottom of the list : 16 August 2024
Oh, before I go any further, T CorB still hasn't "gone". Yet.
• Portability of Fortran's `do concurrent' on GPUs How to execute code on $GPU$ in a relatively transparent manner - because those who write the code may not know who is running the code, and on what hardware. - Really, that's very interesting. But is it astronomy?
• Time-Evolution Images of the Hypergiant RW Cephei During the Re-brightening Phase Following the Great Dimming A year and a bit ago, there was much screaming and shouting about Betelgeuse having a "dimming event". But this is normal behaviour for relatively large large stars. Totally normal.
• 28 August 2024 - A synchronous moon as a possible cause of Mars’ initial triaxiality
  Oh, that's interesting. Mars presents a lot of questions because it isd the closest Earth-a-like we can study in any detail.
  On the other hand, many people forget how different Mars is to Earth (@twitter.com@elonmusk - are you listening? Of course not - you talk, not listen.) Yes (FTFA), "It turns out that a moon of less than a third of the lunar mass was capable of producing a sufficient initial triaxiality." may be true, but it glosses over that Mars is now (and probbly always was) one tenth of Earth's mass. So, presenting the same data differently suddenly sounds less impressive : "It turns out that a moon of three times the relative lunar mass of Luna to Earth ..." sounds less impressive. That, and requiring a deus ex machina to take the moon off-stage before we get to see it ... unconvincing. It's plausible that the author (one-off : Michael Efroimsky, US Naval Observatory, Washington DC 20392 michael.efroimsky @ gmail.com! ; always a good sign of something that hasn't passed an in-house peer review before seeing the outside world. The author may be right, but as it stands, it's his name that he'll blacken, not his institution) is correct, but I won't hold my breath.
  Maybe worth reading about the "initial tri-axility" though. Between rotational forces, and the possibility of small bodies to exhibit "single-plate tectonics" (never (??) seen on Earth), there are some interesting questions there. Wossname did an interesting SETI "lunchtime lecture" on the Martian "hemispheric dichotomy" (N. Polar Basin vs Southern Highlands) a number of years ago. Accepting the "giant impact" hypothesis for that structure (itself a natural expectation of "hierarchical growth" - little things accrete to make bigger things), then the possibility that after the last "giant impact" the body is significantly non-spherical becomes sort-of obvious. not guaranteed though - late-stage impacts are going to deliver enough energy (which cannot leak away fast enough) that the planet is effectively a drop of a low-viscosity fluid. And you've got to have a large enough body (Moon-size, or larger ; the Moon is about 1.25% of the mass of the Earth) close enough to affect the shape of the (slowly) cooling mass. Hmmm. Before reading TFP, that's not looking very liklely. OK, I've done enough thinking on this, it's worth it's own post.

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