I think that notion arises because the Sun is in the middle of the Hertzsprung-Russell diagram.
The sun is a typical mid-life, mid sequence star, but a bit smaller than average.
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Thing is it’s not average - only if you consider its position in the H-R diagram but that really just saying something about where it is in its evolution. Size wise it’s in the 80th percentile.
Most stars in the universe from what we can tell are red/brown dwarfs. I saw a Pareto once and the size drops of quickly so you have this very long tail.
Most stars in the universe from what we can tell are red/brown dwarfs. I saw a Pareto once and the size drops of quickly so you have this very long tail.
If we compare the Sun's properties to neighbouring stars, in no way does it have 'average' or 'typical' stellar properties.
A more typical star within our galaxy would be Proxima Centauri - a low mass, M-dwarf, main sequence star.
In statistical terms, 'average' only applies if the objects being studied have a normal (or Gaussian) distribution.
As you have pointed out, the mass distribution of stars is non-normal, the lowest mass stars being most numerous.
If my memory serves me right, the term normal refers to the range of elements that lie one standard deviation below, the infimum, and above the mean, the supremum.
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An interesting discussion would be, to delve into how the random motion of high temperature plasmas, give rise to ordering of electrons and positively charged nuclei to create extremely intense magnetic fields. This, again, if I am not mistaken, has to do with complex dynamics of systems comprised of huge aggregates of elements with many degrees of freedom. Again, if I am not mistaken, it is believed biological brains, which are comprised of billions of heavily interconnected neurons, function using the dynamics of complex dynamics.
Post Scriptum:
An interesting discussion would be, to delve into how the random motion of high temperature plasmas, give rise to ordering of electrons and positively charged nuclei to create extremely intense magnetic fields. This, again, if I am not mistaken, has to do with complex dynamics of systems comprised of huge aggregates of elements with many degrees of freedom. Again, if I am not mistaken, it is believed biological brains, which are comprised of billions of heavily interconnected neurons, function using the dynamics of complex dynamics.
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Interesting that some of the Red dwarf stars have a predicted lifespans of 100 billion years. One would hope long enough for complex life to form. Problem is most planets that orbit them in the Goldilocks zone are tidally locked which more often than not is problematic as this encourages thermal runaway ie greenhouse effect.
There was a very interesting show on the BBC about 15 or twenty years ago where a bunch of astrophysicists and biologists were tasked with imagining a planet with a thick, oxygen rich atmosphere orbiting a red dwarf. Fascinating show - maybe someone here remembers it.
In this case, IIRC the imagined planet was actually an Earth-sized moon orbiting a large gas giant type planet which in turn orbited the red dwarf so this is how they got around the tidal locking problem.
There was a very interesting show on the BBC about 15 or twenty years ago where a bunch of astrophysicists and biologists were tasked with imagining a planet with a thick, oxygen rich atmosphere orbiting a red dwarf. Fascinating show - maybe someone here remembers it.
In this case, IIRC the imagined planet was actually an Earth-sized moon orbiting a large gas giant type planet which in turn orbited the red dwarf so this is how they got around the tidal locking problem.
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I get cross at people who install street lighting at the blue end of the spectrum. Even on Portsmouth sea front, we are blinded by Mercury lighting. Never mind cars and bikes with blue LED headlamps.
There is a very interesting website known as International Dark-Sky Association | IDA | Light Pollution. Astronomers hate light pollution. And surprisingly you see better in the dark without glare. Criminals beware. 😀
I keep telling the local politicians that dark skies cost nothing.The Riemann or Euler Zeta function for second order proves that the main street-lighting event is the one over your head. By a fraction of 2/3. Not the stuff far away, which does next to nothing except look bright. And what you have should point down rather than up and sideways and be more yellow than blue so as not to destroy your night vision: Riemann zeta function - Wikipedia.
The Goldilocks zone actually varies with the Sun's brightness. I learnt this from Professor Brian Cox's superb look at our Solar System: BBC iPlayer - The Planets.
There is a terrific book by Professor Ian Stewart about celestial mechanics. Even classical mechanics is full of surprises about stability. Mercury could be anywhere in a few billion years time. Even off into interstellar space. The outer planets go all over the place. Asteroids have a life of their own. Calculating the Cosmos: How Mathematics Unveils the Universe: Amazon.co.uk: Stewart, Professor of Math and Gresham Professor of Geometry Ian: 9780465096107: Books
Strangest of all was a night in 1987. We all slept badly in the house. Saw a bright flash in our heads. Our resident Physics genius explained that a star had gone Supernova some distance away. SN 1987A - Wikipedia.
Apparently a burst of Neutrinos. Well, I was there! 😱
There is a very interesting website known as International Dark-Sky Association | IDA | Light Pollution. Astronomers hate light pollution. And surprisingly you see better in the dark without glare. Criminals beware. 😀
I keep telling the local politicians that dark skies cost nothing.The Riemann or Euler Zeta function for second order proves that the main street-lighting event is the one over your head. By a fraction of 2/3. Not the stuff far away, which does next to nothing except look bright. And what you have should point down rather than up and sideways and be more yellow than blue so as not to destroy your night vision: Riemann zeta function - Wikipedia.
The Goldilocks zone actually varies with the Sun's brightness. I learnt this from Professor Brian Cox's superb look at our Solar System: BBC iPlayer - The Planets.
There is a terrific book by Professor Ian Stewart about celestial mechanics. Even classical mechanics is full of surprises about stability. Mercury could be anywhere in a few billion years time. Even off into interstellar space. The outer planets go all over the place. Asteroids have a life of their own. Calculating the Cosmos: How Mathematics Unveils the Universe: Amazon.co.uk: Stewart, Professor of Math and Gresham Professor of Geometry Ian: 9780465096107: Books
Strangest of all was a night in 1987. We all slept badly in the house. Saw a bright flash in our heads. Our resident Physics genius explained that a star had gone Supernova some distance away. SN 1987A - Wikipedia.
Apparently a burst of Neutrinos. Well, I was there! 😱
Compared to the normal neutrino flux from the Sun (about 100 billion neutrinos passing through each square centimetre of your body every second) the odd one or two from the distant Supernova will have been quite insignificant!
The bright flash you saw, Steve, was probably a flash of inspiration as you solved yet another loudspeaker crossover problem! 😀
You may be referring to the UK's Channel 4 programme 'Extraterrestial' in which a team of scientists examines two hypothetical examples of realistic worlds on which extraterrestial life could evolve: a tidally locked planet orbiting a red dwarf star and a large moon orbiting a gas giant in a binary star system.
Extraterrestrial (TV program - Wikipedia)
Our resident Physics genius Simon Jones was actually a bit of a menace. He propped his Lager glass on his window ledge one Summer's day in London.
Come a gust of wind and his net curtains billowing, and it toppled onto my balcony below. Missing my head by inches and alarming me greatly. 😱
Of course a miss is as good as a Mile. I had no hard feelings about it.
AFAIK, Simon ended up in the Patent Office, just like Albert Einstein. He could explain Dirac's equation on the back of a beer mat.
I have been enjoying the current Netflix "Star Trek: Discovery" lately. Ludicrous idea that we can go faster than light, IMO. Warp Factor One it is! No more. 😀
The great mystery about the Universe, IMO, is why only two massive particles are actually stable. The Electron and the Proton. And wherever you go in space or time, they look the same. And 99% of the relevant Physics is to do with the Electromagnetic Force.
I have always loved Number Theory. This strange and seemingly useless stuff about prime numbers, squares and cubes an' all that. I believe we live in a Mathematical Universe:
Quanta Magazine
But Honestly, I am too thick to get it. 😱
Come a gust of wind and his net curtains billowing, and it toppled onto my balcony below. Missing my head by inches and alarming me greatly. 😱
Of course a miss is as good as a Mile. I had no hard feelings about it.
AFAIK, Simon ended up in the Patent Office, just like Albert Einstein. He could explain Dirac's equation on the back of a beer mat.
I have been enjoying the current Netflix "Star Trek: Discovery" lately. Ludicrous idea that we can go faster than light, IMO. Warp Factor One it is! No more. 😀
The great mystery about the Universe, IMO, is why only two massive particles are actually stable. The Electron and the Proton. And wherever you go in space or time, they look the same. And 99% of the relevant Physics is to do with the Electromagnetic Force.
I have always loved Number Theory. This strange and seemingly useless stuff about prime numbers, squares and cubes an' all that. I believe we live in a Mathematical Universe:
Quanta Magazine
But Honestly, I am too thick to get it. 😱
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You'll eat your words once you've seen the Einstein-Rosen Bridge (aka wormhole) in the Delta Quadrant! 🙂
Dodging flying glasses used to be the lager drinker's occupational hazard in certain Glasgow pubs! 😀
I gotta be terribly careful to stay within Forum Rules here.
To me, a "certain" author called Mark was terrifically humorous and entertaining while telling his yarns. Someone I enjoy as much as Raymond Chandler or James Ellroy or James Lee Burke. The first modern writer. Fast and to the point.
About 2,000 years ago. The "Learners" were stuck on a boat out in the Sea of Galilee during a Storm. They feared for their lives. What I found entertaining, was that they just didn't apply any logic. If a certain person was onboard, they were scarcely going to perish. I mean, REALLY!
"Why be Ye Afraid?" as the guy said. I'll stop there. 😎
To me, a "certain" author called Mark was terrifically humorous and entertaining while telling his yarns. Someone I enjoy as much as Raymond Chandler or James Ellroy or James Lee Burke. The first modern writer. Fast and to the point.
About 2,000 years ago. The "Learners" were stuck on a boat out in the Sea of Galilee during a Storm. They feared for their lives. What I found entertaining, was that they just didn't apply any logic. If a certain person was onboard, they were scarcely going to perish. I mean, REALLY!
"Why be Ye Afraid?" as the guy said. I'll stop there. 😎
Whoops, I was thinking this thread was called "The End of the Universe"! I must be running a fever... 😱
Here's an interesting thing we think we know.
Matter seems to dominate over anti-matter in the Universe. Logically there ought to be as much anti-matter as matter. So where is it? Or where did it go?
The neutral Kaon particle was discovered back in the 1950's. This violates CP-symettry aka Charge-Parity symettry: CP violation - Wikipedia
Briefly, the matter particle decays at a different rate from the anti-matter version. Very odd.
It is possible, and I'm no great shakes on Particle Physics. that anti-matter is all around us in some form. Just we don't interact with it hardly at all, except through gravity. And it ought to be spinning opposite to matter to balance the equation.
We had a related topic at a certain forum. Is the Universe spinning? And if so, in what direction? Our Solar system is certainly spinning anti-clockwise when viewed from above the North Pole.
More research needed. 😎
Here's an interesting thing we think we know.
Matter seems to dominate over anti-matter in the Universe. Logically there ought to be as much anti-matter as matter. So where is it? Or where did it go?
The neutral Kaon particle was discovered back in the 1950's. This violates CP-symettry aka Charge-Parity symettry: CP violation - Wikipedia
Briefly, the matter particle decays at a different rate from the anti-matter version. Very odd.
It is possible, and I'm no great shakes on Particle Physics. that anti-matter is all around us in some form. Just we don't interact with it hardly at all, except through gravity. And it ought to be spinning opposite to matter to balance the equation.
We had a related topic at a certain forum. Is the Universe spinning? And if so, in what direction? Our Solar system is certainly spinning anti-clockwise when viewed from above the North Pole.
More research needed. 😎
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Matter and antimatter all but annihilated each other early in the universe's history, and in the process the universe was filled with light.
An example of this process is when an electron and an anti-electron (or positron) annihilate each other and their mass is converted into energy in the form of a photon of light.
Everything that makes up the universe today is simply the residue of the incomplete cancellation of matter and antimatter. The balance was very slightly tipped in the favour of matter. It is estimated that, for every 100 billion matter particles made just after the Big Bang, only one survived.
In the early universe, there was a balance between pairs of electrons and positrons colliding to form photons and the reverse process of photons colliding to create an electron/positron pair.
However, the reverse process isn't so easy as it requires the photons to carry a certain minimum quantity of energy just to create the mass of the electron and proton.
As the temperature of the expanding universe dropped, collisions having enough energy to create electron/positron pairs occurred less often than pairs were being destroyed by annihilation.
I just like how elements heavier than iron are formed due to the pressure of the xploding star.
.. well that and everything else
.. well that and everything else
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