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ESO telescope sees surface of dim Betelgeuse
- deleted 7y ago[deleted]
- stevespang 7y agoBeacause all the light coming from this star is so far away, the events we are now witnessing occurred millions, if not billions of years ago - although high levels of radiation can still reach us from a supernova for example, muons in particular. Seems the earth could use a massive shield, is it possible for the moon were to be "manipulated" in it's orbit such that it could be "steered" to a stationary point to block a stream of radiation from such an event ? Elon, get to work . . .
- SiempreViernes 7y agoThe original ESO press release is probably a better link, as the phys.org text mostly just a small bit of context but doesn't include the "before" pictures or links to any further details. https://www.eso.org/public/news/eso2003/ https://www.eso.org/public/news/eso2003/
- Defenestresque 7y agoThanks! I was very curious about the before/after comparison but didn't see a working link in the original article. Here is the direct YT link (from your article): https://youtu.be/o1ls7Gr9LTE https://youtu.be/o1ls7Gr9LTE This truly seems like a completely massive change in the observable characteristics of the star especially on such a short timeframe. 36% dimmer in 12 months? I'll be really interested to see if we can find out for sure what's happening.
- tigershark 7y agoNo, 36% of its normal brightness, so it’s about 1/3 as bright as usual.
- SiempreViernes 7y agoImpressive that they managed to resolve the surface with just adaptive optics, and that they didn't require a fulll optical interferometry measurement.
- deleted 7y ago[deleted]
- bkloppenborg 7y agoBetelgeuse is ~47 milliarcseconds in diameter, making it one of the largest stars (in angular diameter terms) observable from Earth. It was first resolved using the Michelson Stellar Interferometer (which had a diameter of 20 meters) in the 1880s. I don't know the observational wavelength for the images in the article (VLT-SPHERE has filters that go from ~1-2 microns), but if the image were in H-band (1.6 micron wavelength) the resolution of the 8.2 meter telescope is ~49 milliarcsecond, putting this image just at the formal resolution limit. Still, quite impressive stuff.
- SiempreViernes 7y agoMan, I don't know how to feel about this information: resolved imaging of stellar disks is from the 1880??! So from the list on wikipedia, I guess they could just do that one star, and didn't learn very much beyond the radius? What's the hottest results in the field of spatially resolved stellar observations?
- jconnop 7y agoThe measurement was apparently made in 1920, not 1880s. Still surprising. https://en.wikipedia.org/wiki/Michelson_stellar_interferometer https://en.wikipedia.org/wiki/Michelson_stellar_interferomet...
- adrianN 7y agoSomebody is getting close to completing their Dyson sphere?
- tyfon 7y agoGood luck dyson sphering that star :) It's massive and very violent! It might be that this violence is causing the dimming by discharging massive amounts of dust and gas. I hope it's a prelude to fireworks but that is unfortunately not probable.
- raxxorrax 7y agoI just hope that there is nobody wanting our sun to explode for scientific curiosity.
- tyfon 7y agoBetelgeuse can not sustain life and it _will_ blow up very soon in cosmic timescales. There is nothing we do to stop it blowing up so yes, I hope to see this event in my lifetime :) Our sun is much more stable.
- detritus 7y agoHow can you know that? I mean, you're probably correct, but given we have precisely one datapoint for life, it's a bit much to extrapolate further - there might be aeons-old silicon-skinned space whales congregating around Betelgeuse for their thrice giga-millennial spawning season, or something... . Probably not. - ed 'thrice kilo or mega millennial' seems a bit less unlikely!
- tyfon 7y agoWell, disregarding radiation resistant space whales (which would be able to migrated to another star anyway), I think it's pretty clear the radiation and onslaught of solar winds from Betelgeuse will sterilise everything in the vicinity. But you are right, nothing can be ruled out ;)
- retro64 7y agoOrion is one of my favorite constellations. Where I grew up, the winter sky was often clear and I spent many hours as a youth gazing up, wondering about it all. Even now, when I saw a pic of Orion after following links from the article, I again couldn’t help but think about how awesome the universe is, and how whatever is going on out there just dwarfs our petty, shitty little Earthy problems.
- cgriswald 7y agoIt's definitely one of the most identifiable constellations and has several bright stars in the sky: Betelgeuse, Rigel (one of the brightest from Earth) and Bellatrix. The Orion nebula is resolvable with binoculars and easily captured in a DSLR (although it'll be blurry if you don't have tracking). A newer favorite of mine is Scorpius (visible now at my latitude ~fivein the morning when I walk my dogs); mostly because of Antares, one of the visibly reddest stars in the sky. (And for similar reason, I'm a fan of Aldebaran/Taurus.)
- susam 7y agoOrion is one of my favourite constellations too! I had a pretty similar childhood experience. I got photocopies of two star charts (for both hemispheres) off a book I found in my school library and began using the star chart for the northern hemisphere to study the night sky. The winter sky was the best. I was and I still am very fond of the winter sky. I never had to refer to the star chart to locate Orion. It was easily the most recognizable constellation in the winter sky. Rigel and Betelgeuse, the two brightest stars in Orion are also easily recognizable. They are situated diagonally opposite to each other in the constellation. While Rigel shines bright white, Betelgeuse is distinctly reddish. When I later learnt about red giant stars, the reddish hue of Betelgeuse made even more sense. And then if we imagine a straight line that roughly passes through the three stars in Orion's belt and extend it eastwards, the imaginary line ends up in the vicinity of Sirius, the brightest star of the night sky.
- brandmeyer 7y agoIf you ever get the chance to look up at the night sky with night-vision goggles, you should take another look. Its a whole new kind of stunning when you can clearly see Barnard's loop as well.
- BurningFrog 7y agoOK, that picture looks more like there is a gas cloud blocking the view than that the star itself is fading. Since it's asymmetrical. BTW, Betelgeuse is more known as Orion's left shoulder.
- jackfoxy 7y agoBetelgeuse is really huge, comparable to the size of the orbit of Jupiter. I'm not an astrophysicist. It seems like that size would make surface asymmetries more likely.
- asdfman123 7y agoGuys, please don't say the name a third time.
- shadowgovt 7y agoSize and perspective matter; a smaller object much closer to us could occlude Betelgeuse. Granted, that object would likely need to be both dark and travelling through interstellar space, two things that would by themselves be noteworthy. Unless it's something much, much closer and in the orbit of our own star... I wonder if they're ruled out Kuiper Belt objects or comets yet?
- gmueckl 7y agoThis dimming has been going on for a long time now. If an object within our solar system were to occlude that star, that wiuld only last a few minutes max before it exits the narrow line of sight again. Keppler's law ensures that. I would also assume that a gas cloud in interstellar space would be too homogeneous to occlude one part of a star much more than the rest.
- shadowgovt 7y agoI agree on the gas cloud estimate, which leaves us with exotic large extrasolar bodies if the star isn't actually changing shape (which IIUC, it also shouldn't be doing...) Curiouser and curiouser.
- jobseeker990 7y agoWhich part of Orion is it? One of the shoulders? which?
- oliveshell 7y agoIt’s Orion’s left shoulder.
- mohaine 7y agoIt is the star on the left, not necessarily the left shoulder. It is only the left shoulder if Orion is facing away from you, which I've always assumed he isn't. Any idea if there is a convention for which direction Orion is facing?
- realreality 7y agoIf he’s facing us, then his scabbard is on his right side, making him left handed. Is Orion left handed?
- onetimemanytime 7y agoWhen it explodes, is it close enough to any damage to us? Maybe, not destroy life or anything, but increase radiation or something else harmful. In other words, should we start running ;) ?
- dhosek 7y agoNo.
- mellosouls 7y agoNo. https://www.discovermagazine.com/the-sciences/what-will-a-betelgeuse-supernova-look-like-from-earth https://www.discovermagazine.com/the-sciences/what-will-a-be... There’s no need to worry about the stellar explosion. A supernova has to happen extremely close to Earth for the radiation to harm life — perhaps as little as several dozen light-years, according to some estimates. Betelgeuse is far outside that range, with recent studies suggesting it sits roughly 724 light-years away, well outside the danger zone. But the supernova could still impact Earth in some surprising ways. For example, Howell points out that many animals use the moon for navigation and are confused by artificial lights. Adding a second object as bright as the moon could be disruptive.
- yazr 7y ago> Over their lifetimes, red supergiants like Betelgeuse create and eject vast amounts of material What % of material is then captured by other forming/formed stars? Doesnt it just end up in interstellar space ?
- Aperocky 7y agoStars are formed in compressed interstellar matter, so in that sense, given enough time, a very significant portion will end up in next stars