measuring LMC's Rotation!

[orin stepanek]

http://hubblesite.org/news/2014/11 Maybe somebodt that lives in the LMC is measuring the MilkyWay's rotation!

[BDanielMayfield]

That link reported that the LMC's rotation rate is once per 250 million years. That's about one galactic year to us. What might this mean?

[neufer]

http://hubblesite.org/news/2014/11
Maybe somebodt that lives in the LMC is measuring the MilkyWay's rotation!

Maybe by a tarantula in the Tarantula Nebula in the constellation Dorado (the dolphinfish).

---

<<In Olaf Stapledon's 1937 science fiction novel Star Maker, there is a group of aliens that live in the Large Magellanic Cloud called the Symbiotics, a super-intelligent symbiotic race composed of telepathically linked arachnoid beings and whale-like ichthyoid beings. The "Symbiotics" are the most advanced intelligent life in the Milky Way Galaxy and its satellite galaxies. The reason is because they combine the manipulative tool-using intelligence of the arachnoids with the contemplative meditative and mathematical intelligence of the ichthyoids. The "Symbiotics" travel in starships equipped with tanks of water for the ichthyoids and piloted by the arachnoids. They conduct vast terraforming projects, terraforming planets in numerous different planetary systems. They also construct large artificial planetoids, hollow spheres filled with water inhabited on the inside by the icthyoids and on the surface by the arachnoids. They have the most advanced and powerful telepathic powers of any race in our galaxy and its satellites and are thus able to stop the War of Galactic Empires within the Milky Way Galaxy by telepathically attacking the military forces of the various Galactic Empires and causing them to have doubts about imperialism. This causes the various Imperial military forces to become totally disorganized. The Galaxy is led into a new era of galactic peace supervised by the democratic and communistic Galactic Community of Worlds, which emerges after the fall of the Galactic Empires.

The novel is one of the most highly acclaimed in science fiction. Its admirers at the time of first publication saw it as one of the most brilliant, inventive, and daring science fiction books. Among its more famous admirers were H. G. Wells, Virginia Woolf, Jorge Luis Borges, Brian Aldiss and Doris Lessing. Borges wrote a prologue for a 1965 edition and called it "a prodigious novel". Lessing wrote an afterword for a UK edition. Freeman Dyson was also a fan, admitting to basing his concept of Dyson spheres on a section of the book, even calling "Stapledon sphere" a better name for the idea. Among SF writers, Arthur C. Clarke has been most strongly influenced by Stapledon.>>

That link reported that the LMC's rotation rate is once per 250 million years. That's about one galactic year to us. What might this mean?

Rotation rate is proportional to the average mass density which is about the same for both.

[Ann]

neufer wrote:
Rotation rate is proportional to the average mass density which is about the same for both.

That sounds prosaically plausible and just a tiny, tiny bit disappointing. Wouldn't it have been cool if the LMC had had a tidally locked rotation because it orbited the Milky Way in a way that is somewhat similar to how the Moon orbits the Earth?

(Yes, yes, I have heard that the Magellanic Clouds might just be passing us by, probably stirring the Milky Way up a little in the process, which is cool too...)

Ann

[neufer]

Rotation rate is proportional to the average mass density which is about the same for both.

That sounds prosaically plausible and just a tiny, tiny bit disappointing. Wouldn't it have been cool if the LMC had had a tidally locked rotation because it orbited the Milky Way in a way that is somewhat similar to how the Moon orbits the Earth?

(Yes, yes, I have heard that the Magellanic Clouds might just be passing us by, probably stirring the Milky Way up a little in the process, which is cool too...)

If the LMC had been "tidally locked" it would have been at its own longer orbital period not that of the Earth's.