Apparently, astronomers have looked at images from the last century, and they’ve found that about 100 stars have gone missing.OMG. One of our Stars has gone Missing!
They are visible in observations from decades ago, but they aren’t there today. There’s no evidence they became black holes, so what’s going on?
One suggestion is that aliens are responsible! An advanced alien civilisation could enclose a star in something like a Dyson sphere in order to collect all of its energy output.
Somehow it's always WW2. You know, living with the idea you could die tomorrow. And who could not love Glenn Miller? A considerable industry still exists in Nostalgia:
The Three Belles.
Galu, Sidney Coleman was the Physicist's Physicist! Admired by Dick Feynman and "Leonardo" Susskind.
For gags, I'd watch his great public lecture "Quantum Mechanics in your Face".
YouTube
I can't believe Bill Clinton was there unless his intern was sitting between him and his wife, but Sidney's: "It's Quantum Mechanics, Stupid" predates Bill's comment that "It's the Economy, Stupid". But a serious hardcore bit of Quantum Mechanics thrown in too.
Interestingly, I mentioned that David Hilbert had good taste in hats. Further investigations reveal he was bald as a badger.
Not many people know that.
The Three Belles.
Galu, Sidney Coleman was the Physicist's Physicist! Admired by Dick Feynman and "Leonardo" Susskind.
For gags, I'd watch his great public lecture "Quantum Mechanics in your Face".
YouTube
I can't believe Bill Clinton was there unless his intern was sitting between him and his wife, but Sidney's: "It's Quantum Mechanics, Stupid" predates Bill's comment that "It's the Economy, Stupid". But a serious hardcore bit of Quantum Mechanics thrown in too.
Interestingly, I mentioned that David Hilbert had good taste in hats. Further investigations reveal he was bald as a badger.
Not many people know that.
Mathematicians are proud to wear their caps and hats! https://www.spreadshirt.co.uk/mathematician+caps+&+hats
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Joan Sims or Sylvia Sims ?
Tough one. I naturally fancied Sylvia. What's not to like?
My acting friends told me she was a hard woman to work with. Interestingly, Sylvia is still alive.
Sylvia, you can call my number. Or PM me.
Tough one. I naturally fancied Sylvia. What's not to like?
My acting friends told me she was a hard woman to work with. Interestingly, Sylvia is still alive.
Sylvia, you can call my number. Or PM me.
Good old Leslie Phillips and Joan Sims in 'Carry on Teacher'. What a 'Ding Dong'!
The 24 year old Joan Sims was hard not to fancy when playing one of the 'Belles' (a teacher actually) in the 'Belles of St Trinian's'.
The 24 year old Joan Sims was hard not to fancy when playing one of the 'Belles' (a teacher actually) in the 'Belles of St Trinian's'.
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Even its science has been analysed! YouTubeBut a great film.
"500 turns each and we get to the top!"
Duality of matter is a weird thing, with particles exhibiting wave like behaviour in certain circumstances, and particle like behaviour in others. A property of any particle is gravitational potential energy. If a particle travels away from an object, it gains gravitational potential energy. Under Quantum Mechanics a photon can be seen as having a mass equivalent to its energy, since mass is energy. The energy of a photon is given by E = hf, where h is Planck's Constant. Using Einstein's E = mc^2, the 'mass' of a photon becomes, m = hf/c^2.
Does a photon exhibit the behaviour of a mass when the dimensions are hugely macroscopic?
Does a photon exhibit the behaviour of a mass when the dimensions are hugely macroscopic?
At the end of which I can offer you a 'Moonlight Serenade'!
As a big band trumpet player, I've played bothof those tunes many times.Thanks for the nice earworms.
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The concept of photons having momentum is more clearly understood in the concept of the solar sail.
A solar sail is a surface that’s attached to lightweight unmanned spacecraft. The sail is designed to reflect incoming photons from the Sun. In doing so, the momenta of the photons is transferred to the sail. This provides a force which pushes the sail, and hence the spacecraft it’s attached to, away from the Sun.
A solar sail is a surface that’s attached to lightweight unmanned spacecraft. The sail is designed to reflect incoming photons from the Sun. In doing so, the momenta of the photons is transferred to the sail. This provides a force which pushes the sail, and hence the spacecraft it’s attached to, away from the Sun.
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Pluto: Back From The Dead
There was a new programme on the dwarf planet this evening (repeated on BBC2 on Thursday at 11.30pm and available on BBC iPlayer).
The New Horizon space probe flyby in 2015 revealed Pluto to be an active and complex world, with mountains carved from ice, a nitrogen glacier that appeared to be moving and a recently active volcano. Scientists have even started to speculate that there may even be alien life on Pluto today.
There was a new programme on the dwarf planet this evening (repeated on BBC2 on Thursday at 11.30pm and available on BBC iPlayer).
The New Horizon space probe flyby in 2015 revealed Pluto to be an active and complex world, with mountains carved from ice, a nitrogen glacier that appeared to be moving and a recently active volcano. Scientists have even started to speculate that there may even be alien life on Pluto today.
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@ Steve
Just read your 'Bite every in a hazelnut'. A classic! How do you get away with it?
Funny as anything IMO. The Joke is that hindsight is always perfect.
This is an age of miracles and wonders, IMO:
I have no wish to go to Pluto. A dull and cold rock, IMO. I have a sensible fear of heights for one thing.
But I am curious if I really saw Apollo 13 fire off to the Moon on Saturday, April 11th. 1970. Apollo 13 - Wikipedia?
I am the first to admit that memory is fallible. But I think I watched Jim Lovell and his buddies fire off to the Moon with my telescope into the Westering evening skies in Epsom, Surrey. 50 years later: Jim Lovell recounts the Apollo 13 disaster | Astronomy.com
Many questions arise. I thought the 2nd or 3rd stage rocket was going right with a puff of smoke. But the new or half-crescent Moon was to the left. Maybe did a lap of Earth orbit before getting on-target.
TBH, maybe I dreamed the whole thing. But I was pretty hot on astronomy in those days. And had many books on the subject.
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