5 ms·

I like thinking about why something that survives interstellar travel might be elongated and off the top of my head I think of what analogous shape is familiar.

I like thinking about why something that survives interstellar travel might be elongated and off the top of my head I think of what analogous shape is familiar. The best way to penetrate mass is with length and density and of course space is “empty” but not over long time scales, and not when you add up interstellar medium over long distances. A big feature of such a shape assuming some stability is a small cross section and the length comes as a side effect of the necessary mass. It makes some sense that an object would be shaped like that but I do wonder what might provide the stability to maintain a small cross section rather than having a more chaotic rotation about some axis other than the radial one. I don’t think we know enough about Oumuamua to say whether this wondering is even relevant to it, but it’s fun to speculate, it could also be Darwinian in a sense. Its stability about a long rotation axis over long periods of time is why we end up seeing it on a long, long, long journey, or it’s something totally different :).

BeefWellington 4y ago
Given its shape and size appears to have changed substantially as it passed through the solar system[1], it seems like the comet theory is the best to explain what it was. In terms of its shape, the article also suggests that was misleading and it may have been much more flat and at least one, possibly two orders of magnitude smaller than originally believed. [1]: https://www.space.com/interstellar-object-oumuamua-pancake-shape-pluto-like-planet https://www.space.com/interstellar-object-oumuamua-pancake-s...
- codezero 4y ago
  Makes sense! Thanks for sharing. I studied comets quite a bit but have been out of academia for a while so I’m no longer as wired into the reality of wild space shit :)
qikInNdOutReply 4y ago
https://revelationspace.fandom.com/wiki/Lighthugger https://revelationspace.fandom.com/wiki/Lighthugger
lamontcg 4y ago
According to wikipedia it has a non-primary axis rotation which is characterized as "tumbling": > ʻOumuamua is not rotating around its principal axis, and its motion may be a form of tumbling.[16][90] This accounts for the various rotation periods reported, such as 8.10 hours (±0.42 hours[18] or ±0.02 hours[17]) by Bannister et al. and Bolin et al. with a lightcurve amplitude of 1.5–2.1 magnitudes,[17] whereas Meech et al. reported a rotation period of 7.3 hours and a lightcurve amplitude of 2.5 magnitudes.[91][n] Most likely, ʻOumuamua was set tumbling by a collision in its system of origin, and remains tumbling since the time scale for dissipation of this motion is very long, at least a billion years.[16][92]
- codezero 4y ago
  There goes my musing out the window, glad that there are smart folks out there doing the real work and folks like you sharing it!

BeefWellington 4y ago

Given its shape and size appears to have changed substantially as it passed through the solar system[1], it seems like the comet theory is the best to explain what it was. In terms of its shape, the article also suggests that was misleading and it may have been much more flat and at least one, possibly two orders of magnitude smaller than originally believed. [1]: https://www.space.com/interstellar-object-oumuamua-pancake-shape-pluto-like-planet https://www.space.com/interstellar-object-oumuamua-pancake-s...

codezero 4y ago
Makes sense! Thanks for sharing. I studied comets quite a bit but have been out of academia for a while so I’m no longer as wired into the reality of wild space shit :)

qikInNdOutReply 4y ago

https://revelationspace.fandom.com/wiki/Lighthugger https://revelationspace.fandom.com/wiki/Lighthugger

lamontcg 4y ago

According to wikipedia it has a non-primary axis rotation which is characterized as "tumbling": > ʻOumuamua is not rotating around its principal axis, and its motion may be a form of tumbling.[16][90] This accounts for the various rotation periods reported, such as 8.10 hours (±0.42 hours[18] or ±0.02 hours[17]) by Bannister et al. and Bolin et al. with a lightcurve amplitude of 1.5–2.1 magnitudes,[17] whereas Meech et al. reported a rotation period of 7.3 hours and a lightcurve amplitude of 2.5 magnitudes.[91][n] Most likely, ʻOumuamua was set tumbling by a collision in its system of origin, and remains tumbling since the time scale for dissipation of this motion is very long, at least a billion years.[16][92]

codezero 4y ago
There goes my musing out the window, glad that there are smart folks out there doing the real work and folks like you sharing it!