*** The Official Astronomy & Universe Thread ***

Soldato
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There is faster than light phenomena that has been demonstrated, quantum entanglement. Einstein called iirc spooky action at a distance. Iirc if something of mass approaches and gets upto light speed its energy and mass become infinite, so that would put a dampener on things.

Yes, there is a lot of poop about the speed of light. It's not a limitation of the Universe, rather there is just a problem with how we can achieve it - the one you state, that as you give a body energy you give it mass, which in turn requires more and more energy to accelerate it. But what if it didn't? Without the Higgs field there is no mass. That thought makes my ears perk up immediately!
 
Soldato
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Anyone recommend a book (ideally pick up and read - I don't want to be reminded of A-levels math) for astronomy / stargazing?
Also drop any youtube channels you find useful for beginners. ty
 
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You're right, the 'official astronomy and universe thread' is the best place to talk about heaven and hell :cry:

Dark energy could also be related to the Panchajanya (conch shell of Vishnu), you never know :D
Oh, so Dark Energy is some sort of Devine consequence, which we have accidently discovered, but weren't suppose to. Raiders of the Lost Ark comes to mind
 
Soldato
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The fact that the Universe is expanding shouldn't really have come as a shock. We never knew what caused it to expand in the first place, so to make assumptions about something you don't understand is pretty obviously a mistake. Especially since Mother Nature loves throwing us curveballs.
 
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It's just amazing that we can even begin to analyse the atmosphere of a planet 120 light years away. It's science I can't even begin to comprehend in my little brain :cry:
Spectral analysis has always been a thing and at its core is really simple, it's only more recently that it's possible with proper detail with JWST now up there able to do that. It's also amazing to think that scopes like JWST will almost certainly be the first to detect hard evidence of biological life on another planet either through a bio signature from the spectral, or a technosignature from the dimming observed over time due to structures orbiting a planet in such a way that it could only be possible artificially.
 
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The fact that the Universe is expanding shouldn't really have come as a shock. We never knew what caused it to expand in the first place, so to make assumptions about something you don't understand is pretty obviously a mistake. Especially since Mother Nature loves throwing us curveballs.
But it did come as a shock to discover it was expanding at an accelerating rate
 
Soldato
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Do any of you watch Star Talk on youtube, the hosts can be annoying but i find it suits me more than very serious channels
 
Soldato
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But it did come as a shock to discover it was expanding at an accelerating rate

But when you think about it, why?

We don't know what caused the universe to expand in the first place, so why are we surprised that it's accelerating?

In retrospect I'm not. And I don't see it as anything particularly special either. It's just another universal constant that we don't understand, just like all the others! We should not have assumed the Universe wasn't accelerating.

I say in retrospect, because if I had been this inciteful before the measurements that showed it to be the case, I would have won a Nobel prize!!! But looking back, now, we should have foreseen this at least as a possibility.
 

SPG

SPG

Soldato
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Yes, there is a lot of poop about the speed of light. It's not a limitation of the Universe, rather there is just a problem with how we can achieve it - the one you state, that as you give a body energy you give it mass, which in turn requires more and more energy to accelerate it. But what if it didn't? Without the Higgs field there is no mass. That thought makes my ears perk up immediately!

Dimensions..... We are getting laughed at by 6yrs olds poking our simple 3D dimensional space with a stick :(
 
Soldato
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To add to this, off the top of my head, it's down to the core needing to be liquid to generate the magnetic field - over billions of years the core cools and starts to solidify, and slowly the magnetic field dissipates allowing the atmosphere to vanish as described above. Earth is much larger than Mars, and so will retain heat in the core a lot longer.
Yes about half the earth's core has solidified eventually it will completely solidify and then the magnetic field will cease but by that time the earth will have turned into another Venus anyhow so its moot. Incidently Venus has no or negligible magnetic field due it have an extremely slow rotation longer than its year infact - and has a tail that streams off into space composed of gas stripped off by the solar wind so its slowly being eroded but being larger to start with than mars theres still a dense atmosphere left. Most of the material is hydrogen that was water vapour that was disassociated by UV radiation in the upper atmosphere the H2 being swiftly lost to space as its so light venus is very dry today but almost certainly had as much water as the earth originally but its all gone lost to space. The same thing happens on the earth but most of our water sits in the oceans rather than the atmosphere so its rate of erosion is much lower

Dark Matter is such a wonderful name, it's perfect for generating research grants. Especially if you happen to think its a particle, it's another excuse for all those experimental particle physicists to start building stuff, even though there isn't that much evidence that it is actually a particle at all.

Same with Dark Energy. Great name. But Einstein already said what it was. It's a constant. But because it has a wonderful name, it's a grant magnet, unlike all the other unexplained constants with really boring names.
Constant? Constant what? You're making zero sense.

Yes, there is a lot of poop about the speed of light. It's not a limitation of the Universe, rather there is just a problem with how we can achieve it - the one you state, that as you give a body energy you give it mass, which in turn requires more and more energy to accelerate it. But what if it didn't? Without the Higgs field there is no mass. That thought makes my ears perk up immediately!
Didn't what? Have mass? Light has no mass but cannot travel faster than the speed of light (through a vacuum). Its a fundamental property of spacetime.
 
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Soldato
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Yes about half the earth's core has solidified eventually it will completely solidify and then the magnetic field will cease but by that time the earth will have turned into another Venus anyhow so its moot. Incidently Venus has no or negligible magnetic field due it have an extremely slow rotation longer than its year infact - and has a tail that streams off into space composed of gas stripped off by the solar wind so its slowly being eroded but being larger to start with than mars theres still a dense atmosphere left. Most of the material is hydrogen that was water vapour that was disassociated by UV radiation in the upper atmosphere the H2 being swiftly lost to space as its so light venus is very dry today but almost certainly had as much water as the earth originally but its all gone lost to space. The same thing happens on the earth but most of our water sits in the oceans rather than the atmosphere so its rate of erosion is much lower


Constant? Constant what? You're making zero sense.


Didn't what? Have mass? Light has no mass but cannot travel faster than the speed of light (through a vacuum). Its a fundamental property of spacetime.

Einstein included Dark Energy in his equations and he called it the Cosmological constant. It is no different to any other constant in the Universe, in that it is a number that we don't understand. There are lots of them. The only reason the Cosmological constant is of such interest right now, is because it has this wonderful alternate name - Dark Energy, also, of course, it turned out that it's value came as a real shock to people.

There is no law that states that nothing can travel faster than light. What Einstein stated is that there is a barrier, in that is currently impossible to accelerate anything with mass to the speed of light. But it isn't an absolute limit, there is no reason to suppose that it's impossible - just we don't yet know how.


 
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Soldato
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It seems back in Nov Voyager 1 broke down, in that the data it was sending was garbage.

They managed to track it down to some damaged code on 1 chip. Then figured out how to remotely reprogram the flight data system to move the corrupt code out of the way and update the rest of the program.

In early April it started communicating properly with NASA again.

Amazing really, to do that with nearly 50 Yr old tech that's currently 15 Bn miles away.

 
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