** The Official Space Flight Thread - The Space Station and Beyond **

mrk

mrk

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Not probably, almost definitely. The universe is of course expanding (Hubble Constant) and the farthest away light sources are moving away at a faster rate than those closer to us. The probability is that it's probably far more than 90 billion years, but we will never ever know or see this to give an estimate on that because once the observable universe horizon has been passed by those light sources, they are gone forever as the speed of expansion beyond that is faster than the light can reach us.

As mentioned previously, at one point in the future every single light we see in the sky will vanish because they have gone beyond that horizon. The night sky will be pitch black. If space was too big now to make contact with any life out there not really feasible without some exotic technology currently yet not even dreamt up, then a time like the above will be something unimaginable on another level :p

Edit*
I was reading this week about how the laws of physics in our universe "may" be changing. It's been long thought that the universe and nature in general could be one living thing that has a delicate balance of everything. The paper isn't peer reviewed yet and the researchers do state caution for their theory but it's an interesting thing for sure and lends itself to those scientists who are pro-living universe that evolves within itself:

https://futurism.com/laws-physics-changing
 
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Soldato
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Not probably, almost definitely. The universe is of course expanding (Hubble Constant) and the farthest away light sources are moving away at a faster rate than those closer to us. The probability is that it's probably far more than 90 billion years, but we will never ever know or see this to give an estimate on that because once the observable universe horizon has been passed by those light sources, they are gone forever as the speed of expansion beyond that is faster than the light can reach us.

As mentioned previously, at one point in the future every single light we see in the sky will vanish because they have gone beyond that horizon. The night sky will be pitch black. If space was too big now to make contact with any life out there not really feasible without some exotic technology currently yet not even dreamt up, then a time like the above will be something unimaginable on another level :p

Edit*
I was reading this week about how the laws of physics in our universe "may" be changing. It's been long thought that the universe and nature in general could be one living thing that has a delicate balance of everything. The paper isn't peer reviewed yet and the researchers do state caution for their theory but it's an interesting thing for sure and lends itself to those scientists who are pro-living universe that evolves within itself:

https://futurism.com/laws-physics-changing

I'm not sure about *every* star going dark. We're going to be stuck with our local galactic cluster, as the forces of gravity will keep them together. Plenty of light there for many years to come.

But yes, everything beyond that will be totally gone. Any civilisation born in that cluster of galaxies will assume that's the entire universe.
 
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One of the theories for the end of the universe (expansion one I think could be wrong) is that eventually all stars will fade away to nothing, starting with the blue stars first as they burn brightest and have shortest lives, then yellow and red super giants, then stars similar in size to our sun, then the red dwarfs, at the moment they have no recorded data of red dwarfs dying via burning through all their fuel as they go through it so slowly they reckon a trillion years plus for that, once there gone it will be husks like white dwarfs and brown dwarfs which will eventually fade to nothing, then the blackholes which slowly radiate away there mass via hawking radiation, even the atoms, electrons, protons, and neutrons will eventually fade to nothing this will however take many many trillions of years.

One of the other theories is the big crunch where expansion hits a point where gravity overtakes it and everything crunches together basically back to the singularity that preceded the big bang. There is also the strange matter theory that some sort of strange matter comes into existence and interacts with regular matter changing it into strange matter and this acts like a virus spreading exponentially until all the universe is made of this strange matter.

https://science.howstuffworks.com/dictionary/astronomy-terms/big-crunch.htm
https://www.bbvaopenmind.com/en/science/physics/strange-matter-last-piece-in-puzzle-of-cosmos/
https://astronomy.com/news/2020/09/the-big-freeze-how-the-universe-will-die

There is a big rip theory as well but I don't remember the details of that one.
 
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It's quite saddening that we'll (and any other alien species in their own) eventually think we're the only galaxy because everything has moved so far apart.
 

mrk

mrk

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I'm not sure about *every* star going dark. We're going to be stuck with our local galactic cluster, as the forces of gravity will keep them together. Plenty of light there for many years to come.

But yes, everything beyond that will be totally gone. Any civilisation born in that cluster of galaxies will assume that's the entire universe.

Ah yes true didn't consider this as forgot about it! Unless bodies in a local group get flung out due to a merger event or something else then yeah they will stick together!
 
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One of the theories for the end of the universe (expansion one I think could be wrong) is that eventually all stars will fade away to nothing, starting with the blue stars first as they burn brightest and have shortest lives, then yellow and red super giants, then stars similar in size to our sun, then the red dwarfs, at the moment they have no recorded data of red dwarfs dying via burning through all their fuel as they go through it so slowly they reckon a trillion years plus for that, once there gone it will be husks like white dwarfs and brown dwarfs which will eventually fade to nothing, then the blackholes which slowly radiate away there mass via hawking radiation, even the atoms, electrons, protons, and neutrons will eventually fade to nothing this will however take many many trillions of years.

One of the other theories is the big crunch where expansion hits a point where gravity overtakes it and everything crunches together basically back to the singularity that preceded the big bang. There is also the strange matter theory that some sort of strange matter comes into existence and interacts with regular matter changing it into strange matter and this acts like a virus spreading exponentially until all the universe is made of this strange matter.

https://science.howstuffworks.com/dictionary/astronomy-terms/big-crunch.htm
https://www.bbvaopenmind.com/en/science/physics/strange-matter-last-piece-in-puzzle-of-cosmos/
https://astronomy.com/news/2020/09/the-big-freeze-how-the-universe-will-die

There is a big rip theory as well but I don't remember the details of that one.

The one you are thinking of is heat death of the Universe, the only one that's actually guaranteed to happen eventually due to laws of entropy.
 
Soldato
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It's quite saddening that we'll (and any other alien species in their own) eventually think we're the only galaxy because everything has moved so far apart.

It’s sad in a way but sort of irrelevant unless you have warp drive / folding space technology to visit those galaxies.
 
Soldato
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Yet another static fire test imminent.

Things feel like they have slowed down I'm know there is a lot going on to prepare "Stage 0"/ground infrastructure, and other stuff that we dont see. Are we also still waiting on the environment assessment etc?
Anyway, I'm getting restless waiting for the next big launch, still a way off for the next. I've been spoiled by the rapid pace of development over the last year or so.
 
Soldato
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If it wasn't designed to accept a refuelling satellite it might be a moot point.

Although if we have reached the point of long term Lunar Gateway habitation maybe our confidence for longer and deeper space missions will grow also.
 
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Ok so this is all over my head. :o

How can we look billions of years into the past with this telescope..?

There’s even more to it than just seeing into the past. As commented, light takes a finite time to travel so you see things as they were in the past - the Sun is 8 light-minutes away so if it were to vanish now, we wouldn’t know about it for 8 minutes, nor would we feel the gravitational effects of the event.

Hubble looked back billions of light years, meaning the light it could see had been travelling since not long after the formation of the Universe, but there are limits.

The further back you go, the more the light has been stretched out in its journey by the expansion of space itself, increasing it’s wavelength. Eventually, it increases so much it goes out of the visible light spectrum and into the infra-red, and Hubble wasn’t able to look at that.

This is one of the reason for James Webb to be placed out beyond the moon - to see in the infra-red, which is also felt as heat, your detector has to be cold. Very cold. The telescope will be at about 30 degrees above absolute zero, something not possible in earth orbit. Using earth itself as a shadow, and it’s own sun shields, will keep the detector cold enough to see the infra-red light - light that left the universe much earlier than Hubble can.
 
Soldato
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This is one of the reason for James Webb to be placed out beyond the moon - to see in the infra-red, which is also felt as heat, your detector has to be cold. Very cold. The telescope will be at about 30 degrees above absolute zero, something not possible in earth orbit. Using earth itself as a shadow, and it’s own sun shields, will keep the detector cold enough to see the infra-red light - light that left the universe much earlier than Hubble can.
Will it also be able to take conventional images like some of the fantastic ones we have seen from Hubble over the years?
 
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