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Where would you travel to if you had an extrasolar spacecraft?

MMohammed

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It's tantalizing enough - and takes a ton of my daydreaming time - to imagine being able to travel around our solar system. However, what if we had the chance/ ability to explore quite a ways beyond that? What if you had an extrasolar spacecraft? Where would you go?

My first thought is to check out some of these carbon-rich exoplanets, just to see how diamond-like they are!
 
Seems like post #1 may be thinking about 14-Feb coming up :) If I was taking this trip, I would desire to know if the exoplanet was indeed earthlike vs. a bad location where I get burned up :) However, a trip to study closely Betelgeuse for example could be interesting.
 
Feb 11, 2021
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I would first go to the moon and completely make sure there is nothing else there. Because the moon is the closest thing to earth I would start there then move forward,
 
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I would head for infinity and beyond, just like Superman. Unfortunately, superman, infinity and time, are all 'made' by man. There is no human on earth with enough brain-power to understand that space and time is endless and neither have a beginning nor end. Just my opinion and this comes from an old man who has nothing better to do than believe his dreams. Watch this space (Pardon the pun)
 

Catastrophe

"Science begets knowledge, opinion ignorance.
I would head for infinity and beyond, just like Superman. Unfortunately, superman, infinity and time, are all 'made' by man. There is no human on earth with enough brain-power to understand that space and time is endless and neither have a beginning nor end. Just my opinion and this comes from an old man who has nothing better to do than believe his dreams. Watch this space (Pardon the pun)

"There is no human on earth with enough brain-power to understand that space and time is endless and neither have a beginning nor end."

What is the problem? Just blank your mind (as in meditation) and float outwards without thinking about stopping. Anyone can do it.

Cat :)
 
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Where would you travel to if you had an extra solar spacecraft?

I think the question is fairly broad spectrum, so can be answered in many different ways. This is apparent to anyone who has read the other responses to the question. What I have decided is that if we had a fuel system that is effectively "unlimited" then in theory the limiting factors to where you would travel to would be governed by the limitations of the human body, so that is the approach that I have taken. In other words, where could we travel to outside the solar system without dying of old age before we get there?

NOTE: I don't plan to talk about the "pseudo science" of perhaps theoretically possible worm holes (not sure) or other types of drive systems from "science fiction" movies and TV shows. I am not against such things but wish to remain inside the theories of mainstream science, rather than the science of our imagination. If I fail in the eyes of others then will happily take a second look at what I have written at some later time.

To get back to the original question, within my noted parameters.

If we had a spacecraft that was capable of travelling to another star system, then we need to ask how long it would take to get there. If it had enough power to accelerate at whatever rate the human body is capable of withstanding then it would still take one hell of a long time to get to Proxima Centauri. This is a red dwarf star that is only 3.8 light years away but it would still take quite a long time to get there. The good news is that if the traveller hasn't died of old age on arrival and found "nothing there worth bothering with" then one may well continue on towards the other two stars that make up the Alpha Centauri system.

The nearer of the two main stars of Alpha Centauri, namely Alpha Centauri A, would probably be less than two light years away when starting from the Red Dwarf, which is of course the nearest star to Sol. Apart from the Alpha Centauri system, there are a few other stars that aren't too far away in terms of how long light takes to travel from one star to another. The problem is that we don't really know how to ACCELERATE fast enough to get "up to speed". There is for example a star approximately 16 light years away that may possibly have a planet that is inhabitable. The problem is that if it takes 16 years when travelling at the speed of light, then even if we were to get to travel at an average speed of about 50% of the speed of light over the entire distance, we would then take well over 30 years. We would need to accelerate close to the speed of light for the first half of the trip and then take the second half of the trip to slow down again. The total travel time would be at least 35 years and that is presuming our human bodies are capable of withstanding almost infinite levels of acceleration.

I think the conclusion from the abovementioned comments and ideas is that we will not be able to travel to very many places at all outside our own solar sytem because it simply takes too long to get there. Having said that, almost everyone wants to believe that there must be some sort of space travel possible, to other star systems that is at least possible, even if impractical, so here is a couple of left field ideas.


I think that if researchers into cures for cancer were to consider that aggressive growths basically don't like cold conditions then we need to learn how to cool the human body down to about 1 - 4 degrees Celsius. That may help to cure cancer but WHAT HAS IT GOT TO DO WITH SPACE TRAVEL? The answer is that if we cool an organism down to just above the freezing point of water then the rate of aging of typical organisms (bacteria, yeast, etc) is about one tenth of what it is at 37.4 Celsius. That means in theory we may take up to 10 times as long to "grow old". What we may also manage to do if we try REALLY HARD with decent funding etc, is have our bodies in a chamber that enables us to be alive without any gas in our lungs or any other part of our bodies. This may sound like a stretch but theoretically our body should also then be capable of withstanding a lot more G forces than the typical 7 or so that would be dangerous for a space traveller under "normal" conditions. It may also be possible that if we were under so much pressure that the freezing point of water would be well below zero Celsius.

Who knows how much slower the ageing process of humans would be if we could even go to about 10 below zero and yet still be "alive". Note that I am not talking here about cryogenics because I am not discussing the possibility of actually freezing us under any sort of conditions. What I am suggesting is more about slowing down the ageing process to some extreme level, but without actually stopping it. I find this possibility more interesting.

As for who may want to travel for such a long time, imagine if certain people were told that their form of cancer is so bad that the only cure is to spend about 5 - 20 years or more existing under these extremely cold conditions that would gradually cause the cancer to die out, due to the cancer cells struggling to survive under conditions unfavourable to them but not to normal cells. This means that a person could conceivably be told that if they stay on Earth then the only way to stay alive is to spend so much time in this "cold chamber" that by the time the individuals are cured their family and friends will have all moved on so that on waking you may not know or recognize many people anyway.

Getting back to the space travel question, if we could be accelerated at about 20 - 30 Gs well then I haven't done the maths so far but I suspect that we could then make it to some close by star system in a time frame of hundreds instead of thousands of years. I don't think cooling our bodies down is going to streatch our life span anywhere near enough. The whole entire process is way too much of a stretch without something else to help us on top of what has been said by me so far. The only thing I can think of to help give us some sort of possibility that isn't too far removed from my version of "proper science" is the idea that maybe we can manage to generate gravity waves under conditions that effectively pull us towards some point in space that is actually directly in front of us and in line with both our departure point and also our destination. I don't know where to begin in expanding on this idea because even then, we may well find that the equipment needed to create these waves would maybe collapse under the strain if the machine wasn't under the influence of the waves that it is relying on to allow us to stay alive while being thrust with so much force in any direction at all.

This response on my part may not be giving the answer that the person posing the question had asked for but is intended by me to be "food for thought" that is directed at those who have a genuine interest in solving the difficult task of justifying the idea of humans being able to travel to another star system and then be able to actually appreciate it after arrival. If we could manage to do it then on arrival I suspect our intrepid travellers wouldn't necessarily be made welcome but who knows! Imagine if intelligent aliens had arrived on Earth at the time that humans only had simple "hunter gatherer" communities. Maybe any well trained humans would be able to give such peoples so much of a helping hand that they would almost feel like gods and would likely be treated as such by at least some of the locals. Maybe those who survived the trip would end up fighting amongst themselves, just like the Greek gods seemed to do.
 
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alien117

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It's tantalizing enough - and takes a ton of my daydreaming time - to imagine being able to travel around our solar system. However, what if we had the chance/ ability to explore quite a ways beyond that? What if you had an extrasolar spacecraft? Where would you go?

My first thought is to check out some of these carbon-rich exoplanets, just to see how diamond-like they are!
I would travel to Alpha Centauri to check if their are any aliens!
 
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It's tantalizing enough - and takes a ton of my daydreaming time - to imagine being able to travel around our solar system. However, what if we had the chance/ ability to explore quite a ways beyond that? What if you had an extrasolar spacecraft? Where would you go?

My first thought is to check out some of these carbon-rich exoplanets, just to see how diamond-like they are!


Dark side of the moon. My ships could explode on landing there, & nobody would know.

No witnesses, no problems

E. Musk
 

Catastrophe

"Science begets knowledge, opinion ignorance.
Where would you travel to if you had an extrasolar spacecraft?

What we are not told is the speed the ESC can attain. In practice it is likely to be (if and when possible) a small fraction of the speed of light. The big problem (as if there were only one ;) ) is the fuel to accelerate and, what is more, if you want to stop when you get there, the fuel to decelerate.
Light speed is 6.706e+8 ( 186,000 x 60 x 60 = 6.696 x 10^8 ) miles per hour
The nearest star is approx 4.3 light years away, or 4.3 x 6,000,000,000,000 or approx 25.8 x 10^13 miles.

Thus 4.3 light years at 1% speed of light would take 25.8 x 10^13 divided by 6.7 x 10^6 or 3.85 x 10^7 hours, or 1.6 x 10^6 days or 4383.56 years. Of course, getting up to speed and slowing down would add to the time, but I think we can probably neglect these. We have shown elsewhere that light sails are out.
Any other ideas?

Cat :)

P.S. I would be happy if someone please checks my maths. :) :)
 
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@Catastrophe, I think you have a X10 error. 4.3 x 6x 10^12 would be 25.8 x 10^12, or 2.58 x 10^13.

But hey, there is also MASSIVE Time dilation due to the velocity. Sure, it'd take (rounding greatly) 430 years to get to the nearest star at 1% of C, but to the passengers it would only be 430/1.00005 = 429.9785 years, or 429 years, 357 days, 4 hours. So, you'd age almost 8 days less than those poor suckers on earth!

Being a long time Space/Science wonk, I would LOVE to believe that there is some way to travel to other stars, but I can't get past the energy it would take to get there in any less than thousands of years. For instance, a SpaceX Falcon Heavy uses ~440 tons of Kerosene and liquid O2 to accelerate 64 tons of payload to ~5 miles per second. With kinetic energy being KE-((MV^2)/2), then you would need the equivalent of (((1,860mps/5mps)^2))*440 [also note that the divide by 2 in KE equation is cancelled by the need to decelerate, which doubles total fuel requirements) = 60,888,000 metric tons of fuel and O2 to accelerate that same 64 tons to 1% the speed of light. Given that 2020 global oil production was 94 million barrels or (94M barrels * 136kG /barrel) = 12,800,000 metric tons, you could say our little rocket would require 5 years of total global oil production! (OK, more than half the 440 tons is O2, and we are ignoring lots of things here) But suffice it to say, chemical rockets won't get us there in 430 years. Everyone that keeps saying "and we'll accelerate to 99% the speed of light" seems to be missing the fact that you'd need to convert Jupiter or something to fuel to make that happen. ;->

So, to get to the stars using any reasonable rocket the first steps might be 1) make people essentially immortal, 2) give them an off switch so they can handle thousands of years of effective hibernation.

We could rerun all this assuming antimatter for fuel. However, making antimatter is a highly inefficient process, and a quick web search returns "Making 1 gram of antimatter would require approximately 25 million billion kilowatt-hours of energy and cost over a million billion dollars."

I'm waiting for warp drive.
 

Catastrophe

"Science begets knowledge, opinion ignorance.
@Catastrophe, I think you have a X10 error. 4.3 x 6x 10^12 would be 25.8 x 10^12, or 2.58 x 10^13.

But hey, there is also MASSIVE Time dilation due to the velocity. Sure, it'd take (rounding greatly) 430 years to get to the nearest star at 1% of C, but to the passengers it would only be 430/1.00005 = 429.9785 years, or 429 years, 357 days, 4 hours. So, you'd age almost 8 days less than those poor suckers on earth!

Being a long time Space/Science wonk, I would LOVE to believe that there is some way to travel to other stars, but I can't get past the energy it would take to get there in any less than thousands of years. For instance, a SpaceX Falcon Heavy uses ~440 tons of Kerosene and liquid O2 to accelerate 64 tons of payload to ~5 miles per second. With kinetic energy being KE-((MV^2)/2), then you would need the equivalent of (((1,860mps/5mps)^2))*440 [also note that the divide by 2 in KE equation is cancelled by the need to decelerate, which doubles total fuel requirements) = 60,888,000 metric tons of fuel and O2 to accelerate that same 64 tons to 1% the speed of light. Given that 2020 global oil production was 94 million barrels or (94M barrels * 136kG /barrel) = 12,800,000 metric tons, you could say our little rocket would require 5 years of total global oil production! (OK, more than half the 440 tons is O2, and we are ignoring lots of things here) But suffice it to say, chemical rockets won't get us there in 430 years. Everyone that keeps saying "and we'll accelerate to 99% the speed of light" seems to be missing the fact that you'd need to convert Jupiter or something to fuel to make that happen. ;->

So, to get to the stars using any reasonable rocket the first steps might be 1) make people essentially immortal, 2) give them an off switch so they can handle thousands of years of effective hibernation.


We could rerun all this assuming antimatter for fuel. However, making antimatter is a highly inefficient process, and a quick web search returns "Making 1 gram of antimatter would require approximately 25 million billion kilowatt-hours of energy and cost over a million billion dollars."

I'm waiting for warp drive.

"I think you have a X10 error. 4.3 x 6x 10^12 would be 25.8 x 10^12, or 2.58 x 10^13."
Can you explain please?
I said: "Thus 4.3 light years at 1% speed of light would take 25.8 x 10^13 divided by 6.7 x 10^6 or 3.85 x 10^7 hours, or 1.6 x 10^6 days or 4383.56 years."
Is there an error in this?
Whatever, thanks for checking as I requested. Let's get this sorted :) :)

Catastrophe
 
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"I think you have a X10 error. 4.3 x 6x 10^12 would be 25.8 x 10^12, or 2.58 x 10^13."
Can you explain please?
I said: "Thus 4.3 light years at 1% speed of light would take 25.8 x 10^13 divided by 6.7 x 10^6 or 3.85 x 10^7 hours, or 1.6 x 10^6 days or 4383.56 years."
Is there an error in this?
Whatever, thanks for checking as I requested. Let's get this sorted :) :)

Catastrophe
Sure. You calculated a total of 25.8 x 10^13 miles to the star, but it’s actually 2.58x 10^13. More simply, if you are traveling 4.3 light years at .01C (1%), then travel time is 4.3/.01=430 years, no need for further equations.
 
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Catastrophe

"Science begets knowledge, opinion ignorance.
Epiphany, you stated:
"More simply, if you are traveling 4.3 light years at .01C (1%), then travel time is 4.3/.01=430 years, no need for further equations."

light years are a unit of distance, not of time.
Therefore 4.3 light years/0,01 = 430 light years, not 430 years.

Cat :)

P.S. Are you saying this is incorrect?
"The nearest star is approx 4.3 light years away, or 4.3 x 6,000,000,000,000 or approx 25.8 x 10^13 miles."?
 
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Catastrophe

"Science begets knowledge, opinion ignorance.
Distance to alpha Centauri in miles:

Search Results
Alpha Centauri/Distance to Earth
25.67 trillion miles

Equals 2.567 x 10^13 miles. You are correct there, thank you.

Therefore I agree 438.356 years instead of 4383.56 years.

But do you really mind which time it takes you?

Cat :) :)
 
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Catastrophe

"Science begets knowledge, opinion ignorance.
Thanks to Epiphany the correct answer is

Therefore I agree 438.356 years instead of 4383.56 years.
But do you really mind which time it takes you?

Remember the question was:
Where would you travel to if you had an extrasolar spacecraft?
We are not told how fast the ESS can travel. Once you go at speeds approaching light there are serious complications (especially starting and stopping) also fuel to accelerate to such speeds.



Cat :) :)

P.S. I ignored relativistic effects which probably would not change the answer materially.
For example, I took 4.3 instead of 4.243 light years for the distance of Proxima Centauri.
And alpha Centauri is 4.367 light years away. So approximations were made.
 
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GN-Z11 galaxy would certainly be my destination. If I had an extrasolar spacecraft, I would travel to the farthest point in our Universe to see something we have never seen, and we'll hardly see.
 

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