5 ms·
No mention of a Dyson sphere[1]? I hope we are witnessing the construction of one! [1] https://en.wikipedia.org/wiki/Dyson_sphere https://en.wikipedia.org/wiki
by strbean 7y ago
No mention of a Dyson sphere[1]? I hope we are witnessing the construction of one!
[1] https://en.wikipedia.org/wiki/Dyson_sphere https://en.wikipedia.org/wiki/Dyson_sphere
- hnuser123456 7y agoIIRC this dimming cycle has been repeating for decades
- petschge 7y agoActually there is several period detected in the brightness, one being ~420 days (give or take 10 days or so), another is ~2100 days. Several of those having a (nearly) simultaneous minimum might very well explain the stronger than normal dimming we just have seen. The other thing that got some attention is that Betelgeuse did not start to rebrighten January twenty-something -- like expected -- but reached a minimum slightly later, on February 10th or so. The correct conclusion of course is not "it is blowing up" but "we got the period length slightly wrong", closer to 425 days or maybe the period length is not exactly constant.
- rbanffy 7y agoAround a star that's going supernova in the next 1e+5 years? No, thanks.
- flashman 7y agomaybe it's stadium seating for a species that doesn't mind a few gamma rays
- ByThyGrace 7y agoOr an alien doomsday cult.
- mnw21cam 7y agoOr a shield to protect things nearby from the coming supernova.
- rbanffy 7y agoA "paranova" is an interesting concept, but it'd probably be more effective to build multiple smaller ones closer to the settled worlds. We may want to build a smaller scale parasol for Venus so it cools down and can be eventually settled.
- shagie 7y agoAssuming using all the mass in the solar system (1.82 10^26 kg), and 1AU, you get something that is about 8-20 cm thick depending on density. r = 1AU gives a surface of 12.57 square AU (that unit boggles my mind as I write this) r = 3.5 AU for Betelgeuse and the surface area is 153.94 AU. That 3.5 puts the sphere at the surface of the star. The 8-20 cm thick surface becomes roughly 0.8 - 2 cm. Betelgeuse is roughly 100,000 times more luminous than the sun (it is a variable star so I'm using a very round number). The habitable zone is a function of luminosity only ( https://www.britannica.com/science/habitable-zone https://www.britannica.com/science/habitable-zone ). The approximation then is for the sqrt(L). For 100,000 this is 316. The habitable would be about 320 AU away from the center of Betelgeuse. This gives the mind boggling large number 1.3 x 10^6 square astronomical units. The thickness of this material on the scale of proteins and Wolfram Alpha says it is about three times the approximate diameter of a carbon nanotube. --- Hoping to see a Dyson sphere around Betelgeuse would stretch the limits of physics. Or I've got my math off in a few places - which is quite possible.
- mr_toad 7y agoAn actual sphere is implausible and probably impractical. (Unstable, no gravity, no atmosphere). There doesn’t seem to be any reason to orbit artificial structures in the habitable zone.
- eric-hu 7y agoWhy would a hypothetical Dyson sphere need to be in the habitable zone? I would guess that it should be built as small as the construction materials can tolerate. Edit: I love that you did napkin math for this, BTW.
- atisu 7y agoJust for the record: the Dyson sphere is not an actual solid hollow sphere around a star. Rather it is a swarm of rotating objects orbiting the star.
- machello13 7y agoYou're thinking of a Dyson swarm.