Interstellar travel
Discussion
Eric Mc said:
The square or the blue smudge within the square?
We've had broadcast radio since about 1900. If you include telegraph messages, we can go back to the 1840s. So you are looking at a circle around 180 or 120 light years from earth.
Aliens picking up earth TV is how the aliens found out about us in the book/movie "Contact" (written by Carl Sagan).
The small blue smudge inside the expanded square. For aliens to come across our signals is the equivalent of being unlucky enough to prick their finger on a needle in a haystack. Make it TV and you'll be limiting to a light sphere 70ish years across. Not the clearest analogy but heopfully you get what I mean We've had broadcast radio since about 1900. If you include telegraph messages, we can go back to the 1840s. So you are looking at a circle around 180 or 120 light years from earth.
Aliens picking up earth TV is how the aliens found out about us in the book/movie "Contact" (written by Carl Sagan).
Eric Mc said:
Mr Whippy said:
Artificial gravity seems an easy fix if you just spin your occupants around?!
On travelling interstellar, I’m sure when the time comes we’ll have no need to for the reasons we think we do now, and to travel there will be like travelling to the local shop on foot… a case of opening and closing a few doors.
The biggie is getting out into our solar system in the short term while we’re undeveloped enough to need it’s resources and safety (eggs not all in one basket)
I was considering the other day the cost of just making a huge hill so you can basically traverse “along the ground” to about 100,000ft or 200,000ft, or wherever it gets a bit tricky.
Once you can get stuff up there super cheaply (assuming you ignore initial cost), and bring stuff back down, it’d seem pretty easy to start building some big equipment for getting out and about.
Also lots of scope for a geostationary ring full of solar panels and stuff to variably shade the Earth and provide energy.
I assume someone has done some quick scribbles on this already?
Ie. Will the plate you build it on just sink/split apart under the weight?
So many misconceptions in one post On travelling interstellar, I’m sure when the time comes we’ll have no need to for the reasons we think we do now, and to travel there will be like travelling to the local shop on foot… a case of opening and closing a few doors.
The biggie is getting out into our solar system in the short term while we’re undeveloped enough to need it’s resources and safety (eggs not all in one basket)
I was considering the other day the cost of just making a huge hill so you can basically traverse “along the ground” to about 100,000ft or 200,000ft, or wherever it gets a bit tricky.
Once you can get stuff up there super cheaply (assuming you ignore initial cost), and bring stuff back down, it’d seem pretty easy to start building some big equipment for getting out and about.
Also lots of scope for a geostationary ring full of solar panels and stuff to variably shade the Earth and provide energy.
I assume someone has done some quick scribbles on this already?
Ie. Will the plate you build it on just sink/split apart under the weight?
Spinning something does not create artificial gravity, it simulates it. What it actually creates is centrifugal/centripetal force. This can create the feel of gravity but there are a number of issues. In a space craft or space station sized object - such as the one depicted in the film "2001" or the rotating section of the Soviet spacecraft in "2010", as well as centripetal force, there will also be some coriolis force in play as well which may very well make rotating spacecraft or rotating sections of spacecraft very tricky. I would imagine that walking around inside a rotating ring or drum might well see you walking at 45 degrees to where you want to go - like being dizzy or drunk.
"I was considering the other day the cost of just making a huge hill so you can basically traverse “along the ground” to about 100,000ft or 200,000ft, or wherever it gets a bit tricky".
Altitude is not the issue when trying to achieve space travel, it's velocity. If you were able to walk to the top of a 200,000 foot hill and stepped off the top - you'd just plummet the 200,000 feet back to earth - like Joe Kittinger or Felix Baumgartner did in their high altitude parachute jumps.
To get off the earth and STAY off the earth, you need to achieve a velocity of around 17,500 mph (to orbit the earth) or 25,000 mph to get away from the earth completely. If you want to travel out of the solar system, you need to achieve solar escape velocity, which is around 37,000 mph. The two Voyager spacecraft are on a genuine interstellar journey as they have achieved solar system escape velocity.
Going round requires an acceleration.
Yes if you then accelerate that spinning item, to move it around, uhhhh. But hey. Either accelerate the ship slowly, or in a constant way which you can consider in the design, etc.
Ie, maybe a constant acceleration section (floor perpendicular to travel), and a steady state section (spinning)
If you’re going a long way you’re gonna need to not waste your body away, otherwise why send humans at all?
The point is we have a handful of solutions that accelerate you so you don’t waste away, that don’t require Star Trek levels of technology.
On the hill. Yes 200,000ft isn’t geostationary.
But there isn’t much air, and there is a lot of momentum. And a decent high-level zone for say solar panels etc.
If you have a big train that drives up the hill and accelerates to high speed (easy with solar power, geothermal, whatever takes your fancy with a project this big), then surely you can just throw stuff off into space with very little effort from such a location.
Even just conventional rockets launched from up there would be on their final booster stage if released from a fast train.
I dunno, lots of reasons it’d be a stupidly large project, but we’re not gonna get where we need to be thinking small and negatively, and looking at all the costs.
If we want a space faring future we need to invest in getting off this rock easily and massively.
Loads of rockets won’t really cut it will they? Especially when we want to bring stuff back down… getting back through the atmosphere isn’t easy either.
Whoozit said:
Eric Mc said:
The square or the blue smudge within the square?
We've had broadcast radio since about 1900. If you include telegraph messages, we can go back to the 1840s. So you are looking at a circle around 180 or 120 light years from earth.
Aliens picking up earth TV is how the aliens found out about us in the book/movie "Contact" (written by Carl Sagan).
The small blue smudge inside the expanded square. For aliens to come across our signals is the equivalent of being unlucky enough to prick their finger on a needle in a haystack. Make it TV and you'll be limiting to a light sphere 70ish years across. Not the clearest analogy but heopfully you get what I mean We've had broadcast radio since about 1900. If you include telegraph messages, we can go back to the 1840s. So you are looking at a circle around 180 or 120 light years from earth.
Aliens picking up earth TV is how the aliens found out about us in the book/movie "Contact" (written by Carl Sagan).
Ie, don’t we use absorption spectra from other planets to look at composition?
Wouldn’t “aliens” just be just as likely to be watching spectra from other planets over time and noting differences indicative of different types of life and events etc?
rustyuk said:
My bet is that we crack how to digitise consciousness and send that at the speed of light before we discover how to send living matter at great speeds and distances.
Then in 10000 years we arrive at Alpha Centauri and discover our AI probe has become Planet SHODAN and our rival AI's can have an interstellar war.Mr Whippy said:
Shirley aliens are going to have better gear than we have wrt scanning the EM spectrum over time?
Ie, don’t we use absorption spectra from other planets to look at composition?
Wouldn’t “aliens” just be just as likely to be watching spectra from other planets over time and noting differences indicative of different types of life and events etc?
Yes but the speed of light limit means our radio waves simply haven't reached very far. So there is, in a real sense, nothing for the aliens outside that radio sphere to observe.Ie, don’t we use absorption spectra from other planets to look at composition?
Wouldn’t “aliens” just be just as likely to be watching spectra from other planets over time and noting differences indicative of different types of life and events etc?
Why do you think the reporting on the deep space telescope discoveries often say something like "peering into the birth of the Universe"? For exactly the same reason. It's taken untold billions of years for the light from that event to reach our planet.
Edited by Whoozit on Wednesday 4th October 19:25
Whoozit said:
Mr Whippy said:
Shirley aliens are going to have better gear than we have wrt scanning the EM spectrum over time?
Ie, don’t we use absorption spectra from other planets to look at composition?
Wouldn’t “aliens” just be just as likely to be watching spectra from other planets over time and noting differences indicative of different types of life and events etc?
Yes but the speed of light limit means our radio waves simply haven't reached very far. So there is, in a real sense, nothing for the aliens outside that radio sphere to observe.Ie, don’t we use absorption spectra from other planets to look at composition?
Wouldn’t “aliens” just be just as likely to be watching spectra from other planets over time and noting differences indicative of different types of life and events etc?
Why do you think the reporting on the deep space telescope discoveries often say something like "peering into the birth of the Universe"? For exactly the same reason. It's taken untold billions of years for the light from that event to reach our planet.
However, this evidence would be extraordinarily difficult to discern from those distances - the view of Earth is blocked for most of our own galaxy by the stars that lie between us, so only relatively nearby star systems would realistically be able to find that evidence. That's still many hundreds or thousands of star systems, but that's only a tiny fraction of those in our own galaxy.
Whoozit said:
Mr Whippy said:
Shirley aliens are going to have better gear than we have wrt scanning the EM spectrum over time?
Ie, don’t we use absorption spectra from other planets to look at composition?
Wouldn’t “aliens” just be just as likely to be watching spectra from other planets over time and noting differences indicative of different types of life and events etc?
Yes but the speed of light limit means our radio waves simply haven't reached very far. So there is, in a real sense, nothing for the aliens outside that radio sphere to observe.Ie, don’t we use absorption spectra from other planets to look at composition?
Wouldn’t “aliens” just be just as likely to be watching spectra from other planets over time and noting differences indicative of different types of life and events etc?
Why do you think the reporting on the deep space telescope discoveries often say something like "peering into the birth of the Universe"? For exactly the same reason. It's taken untold billions of years for the light from that event to reach our planet.
Edited by Whoozit on Wednesday 4th October 19:25
For what it’s worth my view is that advanced “aliens” are in essence going to be doing is what the 3D person is doing when interacting with the 2D world in Flatland.
They’re not “travelling” in 3D space to get here, they’re doing exotic stuff like folding space or equivalent things that make distances completely irrelevant.
Mr Whippy said:
Whoozit said:
Mr Whippy said:
Shirley aliens are going to have better gear than we have wrt scanning the EM spectrum over time?
Ie, don’t we use absorption spectra from other planets to look at composition?
Wouldn’t “aliens” just be just as likely to be watching spectra from other planets over time and noting differences indicative of different types of life and events etc?
Yes but the speed of light limit means our radio waves simply haven't reached very far. So there is, in a real sense, nothing for the aliens outside that radio sphere to observe.Ie, don’t we use absorption spectra from other planets to look at composition?
Wouldn’t “aliens” just be just as likely to be watching spectra from other planets over time and noting differences indicative of different types of life and events etc?
Why do you think the reporting on the deep space telescope discoveries often say something like "peering into the birth of the Universe"? For exactly the same reason. It's taken untold billions of years for the light from that event to reach our planet.
Edited by Whoozit on Wednesday 4th October 19:25
For what it’s worth my view is that advanced “aliens” are in essence going to be doing is what the 3D person is doing when interacting with the 2D world in Flatland.
They’re not “travelling” in 3D space to get here, they’re doing exotic stuff like folding space or equivalent things that make distances completely irrelevant.
Eric Mc said:
Mr Whippy said:
On the hill. Yes 200,000ft isn’t geostationary.
But there isn’t much air, and there is a lot of momentum. And a decent high-level zone for say solar panels etc.
Nope - you don't get much boost to orbital velocity by launching from an altitude of 200,000 feet. But there isn’t much air, and there is a lot of momentum. And a decent high-level zone for say solar panels etc.
There is fractionally more KE due to altitude. Fractionally less gravity.
Almost zero air resistance.
Depending on altitude temperatures can be near sea level temps, or much lower. Maybe preferable for a big maglev accelerator?
Shirley having a big maglev at say 50,000ft or ideally over 100,000ft is going to remove most issues with getting big stuff into space?
Of course I’ve no idea how viable hundreds of thousands or millions of launches are with hydrogen and oxygen burning… taking loads of small parts up to space, vs a sky-high platform sending up finished machines/facilities in one go… and equally bringing stuff back down much more easily.
One way or another we either need to make getting stuff into space easier.
Or making stuff in space from things sourced in space.
Is the working logic that we’ll get by with oxygen hydrogen rockets until we have facilities sufficient to make stuff in space, negating the need for superior ways of getting into space?
Ie, for at least a hundred years at least at this rate, I’d assume?
Whoozit said:
Well yeah, with FTL capability then lots of things become possible. Although needle and haystack still applies. Monitoring in vaguely real time a volume of space a few hundred thousand years across will take a loooot of listening stations, each of which need access to FTL comms.
It’s still a bit 2D trying to understand 3D here isn’t it?I suppose we need aliens that are very advanced but are constrained by lots of physical things that we find ourselves constrained by.
I think what is more likely is that aliens that can find us simply think better of contacting us, because they’ll be so far advanced not in just technology, but as an entity, that perceptions will just be on a completely different level.
To find aliens like humans, but more advanced, fannying around near us, but in secret, highly unlikely.
Just what would be their motive?
I think we’re pretty much going to be alone until we evolve to not see the universe the way we do.
And when we can see it all for what it truly is, we will realise we don’t need to travel around it in machines… we’ll just travel around it in our minds… peeking in at stuff from our extra dimensions of perspective.
Mr Whippy said:
I’m not really talking about orbital velocity boost either.
There is fractionally more KE due to altitude. Fractionally less gravity.
Almost zero air resistance.
Depending on altitude temperatures can be near sea level temps, or much lower. Maybe preferable for a big maglev accelerator?
Shirley having a big maglev at say 50,000ft or ideally over 100,000ft is going to remove most issues with getting big stuff into space?
Of course I’ve no idea how viable hundreds of thousands or millions of launches are with hydrogen and oxygen burning… taking loads of small parts up to space, vs a sky-high platform sending up finished machines/facilities in one go… and equally bringing stuff back down much more easily.
One way or another we either need to make getting stuff into space easier.
Or making stuff in space from things sourced in space.
Is the working logic that we’ll get by with oxygen hydrogen rockets until we have facilities sufficient to make stuff in space, negating the need for superior ways of getting into space?
Ie, for at least a hundred years at least at this rate, I’d assume?
Nope - still doesn’t work. If it did, they’d all be hoisting rockets to 200,000 feet using balloons - and they don’t.There is fractionally more KE due to altitude. Fractionally less gravity.
Almost zero air resistance.
Depending on altitude temperatures can be near sea level temps, or much lower. Maybe preferable for a big maglev accelerator?
Shirley having a big maglev at say 50,000ft or ideally over 100,000ft is going to remove most issues with getting big stuff into space?
Of course I’ve no idea how viable hundreds of thousands or millions of launches are with hydrogen and oxygen burning… taking loads of small parts up to space, vs a sky-high platform sending up finished machines/facilities in one go… and equally bringing stuff back down much more easily.
One way or another we either need to make getting stuff into space easier.
Or making stuff in space from things sourced in space.
Is the working logic that we’ll get by with oxygen hydrogen rockets until we have facilities sufficient to make stuff in space, negating the need for superior ways of getting into space?
Ie, for at least a hundred years at least at this rate, I’d assume?
Mr Whippy said:
It’s still a bit 2D trying to understand 3D here isn’t it?
I suppose we need aliens that are very advanced but are constrained by lots of physical things that we find ourselves constrained by.
[snip]
I think we’re pretty much going to be alone until we evolve to not see the universe the way we do.
And when we can see it all for what it truly is, we will realise we don’t need to travel around it in machines… we’ll just travel around it in our minds… peeking in at stuff from our extra dimensions of perspective.
Ah well yes. God mode. Somewhat of a cheat code answer to this thread, don't you think I suppose we need aliens that are very advanced but are constrained by lots of physical things that we find ourselves constrained by.
[snip]
I think we’re pretty much going to be alone until we evolve to not see the universe the way we do.
And when we can see it all for what it truly is, we will realise we don’t need to travel around it in machines… we’ll just travel around it in our minds… peeking in at stuff from our extra dimensions of perspective.
Eric Mc said:
Nope - still doesn’t work. If it did, they’d all be hoisting rockets to 200,000 feet using balloons - and they don’t.
Can a balloon get to 200,000ft?You’re still missing the point about going very fast at high altitude too.
Once you’re out of the bulk of the atmosphere surely a fast moving carriage type release is pretty simple too, unlike running rocket launches off aircraft in the thick of it.
It sounds like you’re saying the atmosphere and starting speed are currently not impediments to getting into space, which begs the question what is?
Mr Whippy said:
Artificial gravity seems an easy fix if you just spin your occupants around?!
On travelling interstellar, I’m sure when the time comes we’ll have no need to for the reasons we think we do now, and to travel there will be like travelling to the local shop on foot… a case of opening and closing a few doors.
The biggie is getting out into our solar system in the short term while we’re undeveloped enough to need it’s resources and safety (eggs not all in one basket)
I was considering the other day the cost of just making a huge hill so you can basically traverse “along the ground” to about 100,000ft or 200,000ft, or wherever it gets a bit tricky.
Once you can get stuff up there super cheaply (assuming you ignore initial cost), and bring stuff back down, it’d seem pretty easy to start building some big equipment for getting out and about.
Also lots of scope for a geostationary ring full of solar panels and stuff to variably shade the Earth and provide energy.
I assume someone has done some quick scribbles on this already?
Ie. Will the plate you build it on just sink/split apart under the weight?
Assuming your “hill” has a pyramid shape, even if you had a steep angle of 45 degrees, a hill of 65,000 m (proper unit equivalent of 200,000 ft) then the base of the pyramid would be a square 65,000 m x 65,000 m with a volume of 13,672 cubic kilometres. For reference Mount Everest is about one cubic kilometre…On travelling interstellar, I’m sure when the time comes we’ll have no need to for the reasons we think we do now, and to travel there will be like travelling to the local shop on foot… a case of opening and closing a few doors.
The biggie is getting out into our solar system in the short term while we’re undeveloped enough to need it’s resources and safety (eggs not all in one basket)
I was considering the other day the cost of just making a huge hill so you can basically traverse “along the ground” to about 100,000ft or 200,000ft, or wherever it gets a bit tricky.
Once you can get stuff up there super cheaply (assuming you ignore initial cost), and bring stuff back down, it’d seem pretty easy to start building some big equipment for getting out and about.
Also lots of scope for a geostationary ring full of solar panels and stuff to variably shade the Earth and provide energy.
I assume someone has done some quick scribbles on this already?
Ie. Will the plate you build it on just sink/split apart under the weight?
Whoozit said:
Mr Whippy said:
It’s still a bit 2D trying to understand 3D here isn’t it?
I suppose we need aliens that are very advanced but are constrained by lots of physical things that we find ourselves constrained by.
[snip]
I think we’re pretty much going to be alone until we evolve to not see the universe the way we do.
And when we can see it all for what it truly is, we will realise we don’t need to travel around it in machines… we’ll just travel around it in our minds… peeking in at stuff from our extra dimensions of perspective.
Ah well yes. God mode. Somewhat of a cheat code answer to this thread, don't you think I suppose we need aliens that are very advanced but are constrained by lots of physical things that we find ourselves constrained by.
[snip]
I think we’re pretty much going to be alone until we evolve to not see the universe the way we do.
And when we can see it all for what it truly is, we will realise we don’t need to travel around it in machines… we’ll just travel around it in our minds… peeking in at stuff from our extra dimensions of perspective.
Talk or warp drives and folding space seem to me not much different than saying you will invent magic and then create a spell to teleport yourself anywhere in the universe.
Skeptisk said:
Whoozit said:
Mr Whippy said:
It’s still a bit 2D trying to understand 3D here isn’t it?
I suppose we need aliens that are very advanced but are constrained by lots of physical things that we find ourselves constrained by.
[snip]
I think we’re pretty much going to be alone until we evolve to not see the universe the way we do.
And when we can see it all for what it truly is, we will realise we don’t need to travel around it in machines… we’ll just travel around it in our minds… peeking in at stuff from our extra dimensions of perspective.
Ah well yes. God mode. Somewhat of a cheat code answer to this thread, don't you think I suppose we need aliens that are very advanced but are constrained by lots of physical things that we find ourselves constrained by.
[snip]
I think we’re pretty much going to be alone until we evolve to not see the universe the way we do.
And when we can see it all for what it truly is, we will realise we don’t need to travel around it in machines… we’ll just travel around it in our minds… peeking in at stuff from our extra dimensions of perspective.
Talk or warp drives and folding space seem to me not much different than saying you will invent magic and then create a spell to teleport yourself anywhere in the universe.
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