https://bigthink.com/starts-with-a-bang/planet-orbiting-3-stars/
"How many stars can a planet successfully orbit before gravitational
interactions compel it to be ejected? For a long time, we had only our own
Solar System to look to for actual data, as we were the only star we knew of
with planets around it at all. It wasn’t until the 1990s that we found planets
orbiting other star systems. Even though stars come in singlets, binaries,
trinaries, and even greater numbers of multi-star systems, we’d only ever found
stars orbiting one — or, at most, two — stars. Even in systems with three or
more stars, planets had only been found orbiting one or two of the stars at
once, with the other star(s) always orbiting much farther out: at distances
where they wouldn’t affect the inner planets’ stabilities.
Why was this the case? There were two main ideas that held sway for decades.
One idea was that planets can orbit stars either closely, in which case their
orbits are dominated by one central star (or a tight binary star) that supplies
their gravity, or far away, as long as they’re far enough so that however many
stars there are behave like a single mass. According to this idea, the only
reason we hadn’t seen planets in wide orbits around trinary (or greater)
systems was because it’s difficult to observe. But a rival idea was that wide
planetary orbits around three or more stars would be fundamentally unstable due
to the nature of the 3-body problem, and gravitational interactions would
quickly kick out any such planets.
While this was contentious for a time, the mystery has been solved with the GW
Orionis system: a still-forming trinary system now known, definitively, to
house planets of its own. For the first time, planets in orbit around all three
stars in the system have been found, suggesting such a configuration is not
only possible, but relatively common. Here’s the story of what we’ve learned."
Via
Fix the News:
https://fixthenews.com/276-nauseously-optimistic/
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
