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I'll have to leave you settling this issue with your fellow countryman here (specifically, from 12:20 to 13:00):
Originally Posted by Christian Miller
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06-22-2026 06:04 AM
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Unrelated to our G-type star, but adding to G-type trivia, if life were to be found on Mars and and a common origin with life on Earth established, it would follow that life originated on Mars, due to Earth's higher G, er, *factor*.
It's like, even a Telecaster will always gravitate to the Super 400, rather than the other way around.
Well, sort of.
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Not sure if you mean photosynthesis will cease due to a problem with the Sun or with the Earth. Originally Posted by BWV
May not even matter, if your confidence in our knowledge of physics is right...
Back in 1995 Rigel was observed to have begin fluctuating over 2.5 magnitude range - that is a red giant's herald it is about to supernova. General public expressed concern because Rigel is only about 60 ly distant. Astrophysicists said not to worry, we won't burn up, there won't be a shock wave that blows the atmosphere off the Earth, and even the protective magnetosphere will be untouched... the observation of Rigel's supernova will just be light we see and neutrinos we don't; supernova have no effect on the Earth.
A Indian graduate student in astronomy wondered about that. There is a good record of about three dozen supernova observations over the last 3-4000 years. One of the few estimates of Earth's attributes that goes that far back is average temperature, so he took the temperature graph and marked the points in time (x-axis) of supernova observations.
He noticed that every supernova observation is followed by a dip down in temperature, then a larger and longer bump up in temperature. The size of these dips/bumps varied with distance of the supernovae from us. A few moments on the calculator and he was ready to add Rigel to the graph.
In his paper the original graph was the upper half of a page. To add Rigel's effect at that same temperature scale (y-axis) he wrote that the graph would have to be 11 more pages tall - that's a factor of 21 time as tall. It looked like Rigel's dip would freeze all the oceans, its bump would boil and vaporize the oceans.
Clearly the additional light will be insignificant with respect to the light we get from the Sun. The neutrinos are so non interactive that one may pass through about 40 ly of lead before "hitting something". So this variation in temperature at the Earth had to be due to the Sun. He knew that the fusion in the Sun's core is kept stable by a regulatory system; fusion creates neutrinos which then act to damp the fusion process. When the neutrino flux increases, the Sun would be cooled and the thermal vs gravity balance would move to shrink the Sun's radius a little. The spherical shell of unspent fuel around the core would also shrink and move closer, but not be consumed because of the slowed fusion rate. When the neutrino flux has passed, the Sun would find itself ramping up the fusion rate at the same time that the unspent fuel shell was closer, causing the Sun to get hotter for a while. The difference with Rigel is because it is so close (both light and neutrino obey inverse square).
There was only one observed supernova in the last century (1987A) in the Small Magellanic Cloud about 200,000 light-years away. Estimates for Rigel are 50% probability in about 50-75 years.
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The simplest way of putting this is that the sun will progressively heat up as it continues its main sequence life, so the habitable zone of the solar system slowly pushes outwards. Originally Posted by pauln
Eventually, due to a number of factors, complex life (based on photosynthesis) will no longer be sustainable on Earth. Simple life may survive longer. Estimates for the end of complex life on Earth vary and are not uncontested, but most figures seem to be between 500 million - 1 billion years in the future. Longer in the future the Earth will end up much like Venus is today.
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Rigel is not a red giant, it's a B class (blue) supergiant. Originally Posted by pauln
While it has entered the late stages of its life (it's at the Helium burning stage) and will go supernova at some point, I'm not seeing an estimate as to when. Probably a while. I think Betelgeuse is more evolved? Not sure. Massive stars have complicated, messy and drama filled lives, and are not something I know a huge amount about.
However, while Rigel's distance is not precisely known, modern observations put it at 900 ly give or take. A Rigel supernovae won't be an issue from this distance, but it would be really cool to look at.
Are you sure it's Rigel you mean? Although, I don't believe there are any evolved massive stars near enough to us to pose an issue.
I vaguely recall some of the physics you mention re temperature variations in the geological record possibly being influenced by supernovae. Don't remember it having anything to do with the sun? Sounds interesting, do you have a reference for this?Last edited by Christian Miller; 06-22-2026 at 08:18 AM.
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They put a turntable in there too. Originally Posted by palindrome
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Where'd you get this from? I don't recall that being said when I studied the subject. Originally Posted by pauln
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What's that SF short where they discover that the star of Bethlehem was actually a supernova that wiped out a whole civilisation?
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It was an Arthur C Clarke, I think - was it 'the Star'? Originally Posted by CliffR
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Sounds about right. I wonder if his Childhood's End is the inspiration for the techbros' insistence on consciousness uploading. Originally Posted by Christian Miller
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Maybe? I kind of feel it’s more likely to be Neal Stephenson. Or Iain Banks or someone. Originally Posted by CliffR
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It's been a few decades since I last read it, but I don't recall uploading as a motif in Childhood's End-more like a kind of evolutionary next-step. I suspect that the techbros are looking to more recent writers, particularly the cyberpunks, or, going back a bit, to John Varley. Originally Posted by CliffR
I won't call myself an expert, but I've been an academic and journalistic specialist in SF since before grad school, and I always find it strange how some folks fail to understand that SF is not so much predictive as speculative, hypothetical, exploratory, and playful--it runs on what Samuel Delany called "subjunctivity"--"what if?" The "hardest" varieties of SF insist on constraints--they only work with the most well-tested understandings of the physical world. Less obsessive varieties depend on "enabling devices"--ideas and devices that literally make the story possible, even when they are unlikely or not possible in our current models. (Time travel and history-redacting is a prime example. Interstellar empires are another, for more complex reasons-why-not.)
The most sophisticated SF writers understand the difference--take a look at the work of Charles Stross, who had deployed a wide range of extreme enabling devices (nanotech, the Eschaton) in order to tell some wild and wooly stories with sharply ironic-satiric edges. Then look at his Saturn's Children sequence, which argues that humans are way too delicate to ever engage in space travel (strongly likely) and that AI/robotics will have to do off-planet work. (Accepting a strong-AI assumption--which drives even more irony and satire.)
Back to the tech bros and other pursuers of SF dreams--I offer Hemingway's curtain line to The Sun Also Rises: "Isn't it pretty to think so."
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Yeah, I seem to remember (again, a very long time ago) that there's a similar idea in 2001, and it's more metaphysical in nature (maybe Olaf Stapledon too, even earlier?). The uploading to silicon hardware is a more recent idea, but I daresay the transhumanists do view this as an evolutionary next step.
Vaguely related. A friend recently sent me this article, which is a pretty good dissection of the ideas surrounding conscious AI. I felt at least one of the arguments put forward was a little weak, and apparently the article has received some rebuttals, but it's nevertheless a pretty thoughtful piece worth reading I'd say.
The Mythology Of Conscious AI
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Clarke does mention the uploading of consciousness into machines as a passing phase into the more metaphysical stage, Originally Posted by CliffR
whatever that is. Here’s the quote from 2001, courtesy of the internet
“And now, out among the stars, evolution was driving toward new goals. The first explorers of Earth had long since come to the limits of flesh and blood; as soon as their machines were better than their bodies, it was time to move. First their brains, and then their thoughts alone, they transferred into shining new homes of metal and of plastic. In these, they roamed among the stars. They no longer built spaceships. They were spaceships.”
Chapter 37, "Experiment"
It’s a bit of a repeated idea in many of his books.
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We only got complex life here.
This is where our view is at.
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'The dominant belief that the Earth is unremarkable and insignificant will come under increasing strain as observations and sky searches continue to indicate that the rest of the observable universe appears to be pristine, natural, and apparently lifeless.'
Edmund King
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Well I think we should have our own "Late Nite" radio talk show..
We can have breaks with our own music and compositions and do an analysis of the tune and then
Back to The Aliens
We will come up with some very creative titles for the show Im sure
Ahh...G-Strings of Venus
Must say some of the ramblings give the impression that some of us have done some "Space Studies"
Always been fascinated by Phd. types saying with confidence..how old/large/ the universe is and its behavior..
what it can and will do and when..and the (almost) exact time of its birth..ahh yes..the Sacred-Big Bang..
Always liked the time/distance framework..Millions of light years--Im sure they have no trouble reconciling a bank statement..
And now on to our first guest..someone who has some classical music background and a good mix of be-bop..
And he is going to reveal how he was abducted at a Rolling Stones concert-that never happened!!
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We can only observe a mere fraction of a possibly infinite universe, and only the 3d portion of it. We speculate on the rest based on what we know of the observable realm, presuming that our local laws of physics will apply throughout, which is a big leap of faith.... what with black holes, randomness, Schrodinger's cat meowing spookily in the distance, Ben Monder, etc. Originally Posted by Litterick
In 1875, a young Max Planck was advised by his physics professor, Philipp von Jolly, against entering the field. Jolly reportedly told him that "in this field, almost everything is already discovered, and all that remains is to fill a few unimportant holes." Originally Posted by wolflen
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None of us here know chemistry real well. Probably some do but very likely they keep quiet.
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Don’t look at me guv, I get a bit confused by molecules. Also, anything heavier than helium is a metal Originally Posted by emanresu
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There is a very good reason to not BELEIVE in aliens:
people open their mouths and sounds come out.
the sounds for words and sentences. it is quite free to do.
It is as simple as that. The popular topic of UFOs, aliens and gods - all a product of the freedom of the vocal chords.
People can do ANYTHING!
Ain't that amazing?
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It do be like that Originally Posted by emanresu
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It's a popular topic because even in Greek mythology we are told the "gods" brought man technological innovation. Prometheus and fire, for example. In the book of Enoch, a fallen angel named Azazel taught weaponmaking and metallurgy. Originally Posted by emanresu
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Still. Just people talking.
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Black triangles, seeing is believing. Originally Posted by emanresu
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