[HN Gopher] Astronomers Watched a Star Disappear. Now JWST Might...
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Astronomers Watched a Star Disappear. Now JWST Might Have Some
Answers
Author : Brajeshwar
Score : 96 points
Date : 2023-10-05 16:17 UTC (6 hours ago)
(HTM) web link (www.universetoday.com)
(TXT) w3m dump (www.universetoday.com)
| marricks wrote:
| Reading the article I figured this event was in our galaxy but
| it's 22 million light years away! Makes sense that other
| telescopes couldn't resolve it.
| suzzer99 wrote:
| The Milky Way is only 100k light years across. So one of those
| two things can't be true. The article says: "N6946-BH1 is in a
| galaxy 22 million light-years away". So it's a different
| galaxy.
| furyofantares wrote:
| Yep! That's what they're saying - that they had mistakenly
| thought it was in the Milky Way until they saw that it's 22
| million light years away.
| KMag wrote:
| I think the GP was just ambiguous with their wording. I think
| they meant "I originally thought this was within our galaxy,
| but later discovered it was 22 million light-years away."
| jdiez17 wrote:
| A Dark Forest strike?
| ASalazarMX wrote:
| The article says
|
| > [..] a more likely model is that the 2009 brightening was
| caused by a stellar merger. What appeared to be a bright
| massive star was a star system that brightened as two stars
| merged, then faded.
|
| But wouldn't it be cool if this was because someone brute-
| forced the nine billion names of god?
|
| https://en.wikipedia.org/wiki/The_Nine_Billion_Names_of_God
| teekert wrote:
| Perhaps some civilization created a Dyson sphere. Or perhaps a
| technologically advanced civilization contained an overly
| aggressive species.
| jowea wrote:
| From what I understand an actual Dyson shell completely
| covering a star is probably out of reach of even such a
| civilization. Would a Dyson swarm make the star disappear?
| bloopernova wrote:
| Spoilers!
|
| Excellent books, I've read them like a dozen times.
| vkou wrote:
| A Dyson sphere wouldn't cause the star to significantly
| brighten and then wink out all at once.
| sillywalk wrote:
| In the book Pandora's Star (see comment above), the Dyson
| sphere wasn't physical, it was some sort of energy-type
| shield.
| teekert wrote:
| You got the reference ;) First thing I thought: if we had
| wormholes we could observe the event again.
|
| And indeed, the brightening is Probably from the
| construction phase of the sphere.
| bell-cot wrote:
| During final assembly of the Dyson sphere, the
| astrodynamics contractor cranks the to-be-enclosed star's
| fusion rate way up - to brake the infall of the segments of
| the spherical shell with light pressure. Then, once all the
| shoring joints between the segments pass their load/shear
| inspections, the general contractor clears the AC to drop
| the fusion rate back to nominal.
|
| From a distance, the now-enclosed star seems to wink out in
| a very brief time.
| CobrastanJorji wrote:
| Or maybe a Pandora's Star scenario!
| bloopernova wrote:
| I've read those 2 books like a dozen times. It might be time
| for another reading lol.
|
| For those unfamiliar: Pandora's Star is by Peter F Hamilton.
| It details humanity's encounter with a star system that is
| completely enclosed in an impenetrable exotic matter/energy
| shell. It's fantastic sci-fi, a great adventure with fun
| characters, loads of bizarre future stuff, and very cool
| action.
|
| Highly, highly recommend!
| RHSman2 wrote:
| Will check it out!
| [deleted]
| snakeyjake wrote:
| >Dark Forest
|
| Dark Forest makes no sense.
|
| If you are an intelligence capable of faster-than-light
| interstellar travel, capable of snuffing out stars, capable of
| collapsing dimensions-- you don't care about anyone else.
| Nobody's going to compete with you for resources.
|
| Scarcity no longer exists. All you care about is energy and you
| have mastered it. Energy is practically infinite to you. You
| can sit off to the side of black holes or neutron stars
| harvesting energy from their relativistic jets.
|
| Finding or controlling a consistent supply of physical matter,
| least of all individual stars and planets, is no longer
| relevant to you. You can just pluck individual hydrogen atoms
| out of the interstellar void and rearrange them using your
| sources of near-infinite energy to transform them into million-
| kilometer-wide cubes of whatever you want.
|
| If someone makes it to your level of mastery of the cosmos, you
| would just share the locations of any of the other several
| hundred billion sources of free and limitless energy.
|
| You ain't killing a star because an inhabitant of one of its
| planets might take your planet over. You haven't needed to live
| on planets for billions of years. You can construct atomically-
| perfect structures of arbitrary size and composition out of
| what we perceive to be the nothingness of space.
|
| You don't need dirt.
| Tronno wrote:
| Humans kill wasps even though we landed on the moon.
| SllX wrote:
| Wasps and humans live different lives inside a closed
| ecosystem with finite resources and energy. The
| hypothetical civilization the parent is describing is
| further away from us technologically than we are from
| wasps.
| blacksmith_tb wrote:
| I think real problem with the Dark Forest hypothesis is
| that it assumes alien civilizations at a very high level
| of technical development would somehow have not also made
| any sort of moral or ethical progress. Even humans, in a
| few thousand years have gone from winner-take-all, kill
| 'em all, to universal human rights, rules of war, etc.
| (sure, we aren't doing a perfect job, but we clearly have
| made some progress - by the time we're sending ships to
| other stars, I'd like to think we'll be farther along
| yet).
| CodeAndCuffs wrote:
| Plenty of people kill for no reason. I wouldn't rule out the
| idea of a non human lifeform doing the same.
|
| I'm not saying I agree with the dark forest. I just wanted to
| assert that the dark forest idea isn't limited to "we have
| something they want". It could also include. "They're jerks"
| sebzim4500 wrote:
| >Scarcity no longer exists. All you care about is energy and
| you have mastered it. Energy is practically infinite to you.
|
| I'm not convinced. There is a big difference between infinite
| and merely very large. I think the demand for energy will
| grow with the supply, as it has for us.
| snakeyjake wrote:
| >I think the demand for energy will grow with the supply,
| as it has for us.
|
| I think if we apply what is happening on Earth that is not
| going to be true.
|
| It seems as though per-capita energy consumption increases
| to a certain point, and then stops. In the US it peaked in
| the 1970s and has fallen such that even with the
| intervening population increases US energy demand has
| barely increased.
|
| Depending on who is counting energy consumption (this is
| all sources of energy not just utility electricity) either
| peaked or plateaued in 2017-2018.
|
| In the US, EU, and Japan energy consumption is decreasing
| (and it is decreasing faster than population loss in
| Japan). There are a number of reasons for this but mostly
| it's efficiency improvements-- which still count!
|
| I think there is only so much consumption that a TYPICAL
| human being can do. Only so much heating and cooling, only
| so much travel, only so many hot showers. Everyone gets to
| that point, and then stops. They don't reach that level and
| start setting up tesla coils for funsies.
|
| Once they reach that apex, efficiency improvements start to
| decrease overall consumption.
|
| If population predictions pan out and a shift to more
| efficient energy production and storage techniques
| continue, I'm willing to bet that in a century the world
| will be using less energy than it is today.
|
| Same thing for hyper-dimensional interstellar megagods.
| There are only so many 100km x 100km x 100km cubes of
| atomically-pure gold one needs in their collection.
| pbh101 wrote:
| Look at what people make in MineCraft. If people had the
| ability to do that in real worlds, they would. In
| addition to the effect you describe, I think energy
| consumption would grow with ergonomics/facility of use.
| midasuni wrote:
| US per capita consumption doesn't count imported foods
| though. If it costs 1MWh to build a dohicky in China and
| that's imported into the US, you don't add 1MWh to US
| consumption (and remove it from China)
| Tepix wrote:
| > If someone makes it to your level of mastery of the cosmos,
| you would just share the locations of any of the other
| several hundred billion sources of free and limitless energy.
|
| I'm not sure that's true. Evolution is competitive. An
| advanced race may decide to remove potential competitors
| before they become a threat.
| Shaanie wrote:
| That's a lot of assumptions which may or may not be true,
| however likely they may seem. There's no telling how another
| life form may reason, hell it might not even reason at all -
| perhaps it's some kind of space fungi or virus which
| traverses space to inhabit planets capable of supporting
| life. Not that I think the dark forest theory is likely, but
| I wouldn't say it makes no sense.
| ck2 wrote:
| Oh a "failed supernova" would be fascinating
|
| There have only been two in our galaxy in relatively modern
| history, 19th century
|
| https://en.wikipedia.org/wiki/Supernova#Observation_history
| nsxwolf wrote:
| Imaging becoming a black hole without getting to explode first.
| It would be a huge letdown. I imagine it must be like when
| you're just about to sneeze, but then can't. Getting all bright
| like that, here's your moment after billions of years...
| then... nothing.
| em-bee wrote:
| or a balloon that doesn't pop but just deflates
| spacecadet wrote:
| Except it formed a black hole?
| eps wrote:
| > Astronomers watched a star disappear
|
| I sure hope one of them wasn't called Dudley Bose [1].
|
| [1] https://en.wikipedia.org/wiki/Commonwealth_Saga
| distract8901 wrote:
| We should absolutely, without question go poking at it. Surely
| there won't be any consequences
| [deleted]
| perihelions wrote:
| https://arxiv.org/abs/2309.16121
|
| Figure 8 looks weird, how they fit a parameterized model to 3
| points?
| queuebert wrote:
| It's the molecular emission spectrum of PAH (polycyclic
| aromatic hydrocarbons) plus a blackbody. Both of these are
| known quite well to atmospheric scientists. The only thing to
| fit was how much of each to add and what the total flux
| normalization was.
|
| (The blackbody is a smooth single hump, while the PAH spectrum
| are the jagged atomic and molecular lines coming from quantum
| mechanical effects, which have discrete energies.)
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