AI clocks first-known 'binary sextuply-eclipsing sextuple star system'. Another AI will be along shortly to tell us how to pronounce that properly Astronomers have discovered the first-known “sextuply-eclipsing sextuple star system,” after a neural network flagged it up in data collected by NASA’s Transiting Exoplanet Survey Satellite (TESS). The star system, codenamed TIC 168789840, is an oddball compared to its peers. Not only does it contain six suns, they’re split …
With the stars orbiting each other on a timescale of days they will not be very far apart. Consider that Mercury has an orbit of 88 days. This means that there are no stable orbits for planets around any single star in the system.
The closer two sets of binaries are orbiting at roughly twice the distance of Mars (or roughly a third of the distance of Jupiter) which would almost certainly exclude a stable orbit around either of those binary pairs.
The only possibility of a stable orbit would be around the 'outer' binary pair. But even there the 8 day orbit of the stars puts them further apart, so a planet would have to be waaaaaaay out to minimum the 'bumpiness' of the changing gravity as the stars orbit. So well past the frost line, and waaaaaaaay beyond the sort of orbit where the tides would be significant. And even well beyond the range at which the suns would just be really bright stars.
I agree that it would be amazing, unfortunately just very unlikely.
That means the suns in each pair, to an observer, pass directly in front of one another in their orbits. Depending on where the observer is! ;-)
Might there be similar systems we can't spot because we see them from far enough above/below to not see the eclipsing and hence the periodic dimming?
Thousands of them. The odds that a pair of stars circling in a randomly aligned orbit will appear to eclipse when viewed from Earth is over 1,000:1 (much the same is true for detecting planets in this way). It's not really known whether there's any tendency for the orbits of widely separated stars to align (say, with the plane of the galaxy), which might improve the odds somewhat.
The plane of a system is determined by the initial collapse of the gas cloud that becomes the star. (IIRC it's determined by the shortest axis of the gas cloud, though I may have misremembered) And the plane of the galaxy has no significant influence on this. So the plane of a stellar system is effectively random in comparison to the plane of the galaxy.
https://www.forbes.com/sites/startswithabang/2018/08/30/our-motion-through-space-isnt-a-vortex-but-something-far-more-interesting/
About half way down is an accurate animation of how the inner solar system is moving as it circles the galaxy. This shows that our solar system is not travelling edge on.
I believe the 'random' arrangement of planes is supported by the results from Kepler, in that Kepler detected planets in a percentage of the systems observed that was consistent with the planes being arranged randomly. If systems had a tendency to align with the galactic plane then there would have been a far higher percentage of systems in which planets were detected.
Oh that's a clever thing. tfb's rule of astronomers clearly applies here: 'whatever trick you think of, however implausible it is to engineer, astronomers will either have been using it for decades, or have considered it in the past but now be doing something cleverer and requiring even more extreme engineering'.
Indeed my new startup's business plan is '(1) invent mad astronomy-related idea from which money can be extracted; (2) wait for the invention of the idea to cause astronomers to have invented it and sorted out all the engineering twenty years ago; (3) profit'. We feel there may be some causality problems with the second step: we are intending to solve these by suggesting a meta company which will frame these causality problems as astronomical in nature, thus causing them to have been solved in the late 1990s. We don't, of course, actually need to start that company: merely suggesting it should be enough we believe.
It is, unless those bodies are far enough apart, that you can consider each separately as a two body system, and each is orbiting the centre of mass of each of the others, in much the same way that the Earth and Moon orbit the Sun together, and you don't have to worry too much about the separate effects of the Sun's gravity on each.
It sort of is - but then with certain ICs its gets dead easy. We live in a 10 body system (well 10 to 100 or more if your picky) and yet our system has been stable for billions of years and you can work out the speed of light to a few 100ths of a percent by observing satellites of Jupiter or Saturn. The Greeks called it the harmony of the heavens and they thought it was epicycles all the way down. I'd bet you could find some kind of stabilising feedback in the resonances of the 6 stars that causes them to stabilise their orbits - as evidenced by finding them!
We live in a 10 body system (well 10 to 100 or more if your picky) and yet our system has been stable for billions of years
for specified values of "stable"
There are a lot of things about our solar system that indicate that this "stability" is only metastability. For instance the late heavy bombardment, the preponderance of craters on every celestial body that doesn't have an active surface to recycle them, shepherd moons in ring systems that form, and break up over observable time scales, the postulated migration of the gas giants from the inner solar system to their current positions, and so forth. There certainly are resonances that stabilise orbits, but the heavens are not some eternal piece of clockwork that never changes.
I found the phrase "That means the suns in each pair, to an observer, pass directly in front of one another in their orbits" in the article very misleading. English is a particularly ambivalent language as many meanings can be ascribed to this. OTOH, KittenHuffer certainly seems a lot more knowledgeable about the matter than I am!
Well, if IBM's marketing department from the early/mid 1960s was in charge, it would "hextuplet", because one would not want the applications engineer blushing when talking about number systems. Although to be fair they did have hermaphroditic cable connectors. Maybe hardware folks are less easily embarrased?
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