Can .99c Be Achieved? Exploring Interstellar Travel Possibilities

In summary, it is theoretically possible to build a vehicle that can accelerate to .99 C, but it would require significant advances in technology that are not currently on the drawing board. Beamed propulsion, matter/antimatter reactions, and Bussard scramjets are not viable options for interstellar travel. The potential for a warp drive to significantly decrease the amount of energy needed for interstellar travel has been proposed, but there are still many challenges and limitations to making it a reality. Wormholes are also a possibility, but they also require technologies that may not be possible to achieve. In short, while the concept of traveling at .99 C is possible in theory, the practicality of achieving it is currently very low.
  • #1
cjackson
39
0
Is it possible to build a vehicle that can accelerate to .99 C?

How would we go about doing something like this?

If at all possible, how many centuries or millennia is it before this can be accomplished?

Could a Bussard scramjet do it?

How large would a laser/maser/gaser have to be to get the craft up to such speed?

How long would it take from the crew's perspective to cross the galaxy?

How big would the craft be? I imagine a lot of fuel would be required even if you could gather propellant along the way - Bussard scramjet. What kind of fuel would be needed?

Would such a vessel help establish a galactic civilization? Or would time dilation make implausible?

What would it look like?

Are any sort of warp drives completely impossible? If so, which of the following would best for interstellar travel: beamed propulsion, matter/antimatter reaction, Bussard scramjet, or something else?
 
Astronomy news on Phys.org
  • #2
cjackson said:
Is it possible to build a vehicle that can accelerate to .99 C?

Theoretically yes.
cjackson said:
How would we go about doing something like this?

No time soon, it would require fantastic advances in technology that don't look to be anywhere on the drawing board.
cjackson said:
If at all possible, how many centuries or millennia is it before this can be accomplished?

Same answer as above.
cjackson said:
Could a Bussard scramjet do it?

I take it you mean "ramjet" and no, http://en.wikipedia.org/wiki/Bussard_ramjet#Discussions_of_feasibility".
cjackson said:
How large would a laser/maser/gaser have to be to get the craft up to such speed?

http://en.wikipedia.org/wiki/Beam-powered_propulsion" [Broken].
cjackson said:
How long would it take from the crew's perspective to cross the galaxy?

At .99c time dilation is 0.07 minutes for every minute for an observer at rest. To cross from Earth to the far side of the galaxy (~70kly) would take 4962.168 years from the perspective of the crew. From one side of the galaxy to the other (~100kly) would take 7088.821 years.
cjackson said:
How big would the craft be? I imagine a lot of fuel would be required even if you could gather propellant along the way - Bussard scramjet. What kind of fuel would be needed?

That question can't be answered because it depends on technologies that haven't been invented yet e.g. how much mass do you need to hold the necessary stable ecology, industry and society. As linked above ramjets would not work.
cjackson said:
Would such a vessel help establish a galactic civilization? Or would time dilation make implausible?

In addition to such a vessel you would also need to be able to terraform otherwise you're not going to have a civilisation. Whether or not it could work as a civilisation is anyone's guess, see the http://en.wikipedia.org/wiki/Fermi_paradox" [Broken] for further discussion.
cjackson said:
What would it look like?

The ship or civilisation? Either question is as unanswerable as a Neanderthal trying to envision Facebook.
cjackson said:
Are any sort of warp drives completely impossible?

On the subject of warp drives http://arxiv.org/PS_cache/gr-qc/pdf/9905/9905084v5.pdf" [Broken]. The "trick" is to change the warp bubble so that it's exterior radius is microscopic yet the interior radius is large enough to accommodate your vehicle (essentially making a warp bubble that's bigger on the inside than on the out). Apparently this would greatly shrink the amount of energy needed to manageable levels. They don't outline how exactly a shell could be build around a ship in such a fashion nor how the ship could leave.

However neither of these approaches fixes the other problems of a warp bubble such as requiring the construction of an exotic matter shell, superluminal signalling to steer/control the bubble and the huge amount of radiation a warp drive subjects you to. There are some interesting (but technical) objections in http://arxiv.org/PS_cache/gr-qc/pdf/0406/0406083v2.pdf" [Broken] that apparently show that a warp drive would only be capable of very low velocities as well as highlighting other problems.

In summary unless you have a way of making speculative impossible exotic matter, it's not going to happen (and might not even if you could).
cjackson said:
If so, which of the following would best for interstellar travel: beamed propulsion, matter/antimatter reaction, Bussard scramjet, or something else?

None of them. For manned interstellar travel beamed propulsion won't be strong enough, M/Am rockets are far too dangerous (your "vessel" is a weapon so powerful that it could easily annihilate the entire surface of Earth countless times over) and the Bussard ramjet won't work.
 
Last edited by a moderator:
  • #3
wow ok a lot of questions about 1 thing. First I think its theoretically possible I guess. If we were to have a ship that ran on our current fuel and managed to build it, it would probably take a thousand years to even get to 99%C and also an almost infinite amount of energy. Space is huge. It would take many generations of people to travel even to the closest stars. If we ever discover a wormhole (or if they even exist), that would be a much better bet. ^ I agree with the warp bubble and have heard stuff about it, but who knows exactly how much faster that would be.
 
  • #4
CosmicEye said:
wow ok a lot of questions about 1 thing. First I think its theoretically possible I guess.

It's theoretically possible but that doesn't mean much. It's theoretically possible to rearrange every star in the galaxy, doesn't mean we'll ever have the knowledge, resources and will to do it.
CosmicEye said:
It would take many generations of people to travel even to the closest stars.

If you want people to survive you also have to be able to build:
  • A stable ecology
  • An industry capable of building and recycling nearly everything
  • A social, legal, political and economical model that allows the society on the ship to survive harmoniously for thousands of years
All of these are extremely http://en.wikipedia.org/wiki/Nontrivial" [Broken].
CosmicEye said:
If we ever discover a wormhole (or if they even exist), that would be a much better bet. ^ I agree with the warp bubble and have heard stuff about it, but who knows exactly how much faster that would be.

Wormholes suffer from the same problem as warp drives, they require probably impossible http://en.wikipedia.org/wiki/Exotic_matter" [Broken].
 
Last edited by a moderator:
  • #5
Please don't forget that, as you get close to the speed of light, tiny specks of the interstellar medium will impact your ship with the kinetic energy of 20 megaton bombs.
 
  • #6
skippy1729 said:
Please don't forget that, as you get close to the speed of light, tiny specks of the interstellar medium will impact your ship with the kinetic energy of 20 megaton bombs.

Doesn't this violate relativity? It seems to imply that certain speeds are the universal norm, and others are inherently fast. I thought the universe was supposed to look the same from any vantage point.
 
  • #7
Algr said:
Doesn't this violate relativity? It seems to imply that certain speeds are the universal norm, and others are inherently fast. I thought the universe was supposed to look the same from any vantage point.

It is. From the perspective of the guy on the ship the speck is traveling at 0.99c, the speck sees the ship doing the same. The energy is the result of the kinetic energy that would be the same regardless of who was traveling at that speed.

However only one of them is experiencing time dilation because one of them has been in an accelerating reference frame and the other in an inertial.
 
  • #8
If you started out from Earth using an ion drive that slowly increased acceleration given enough time it would reach .99c.

You have to also remember time dilation and length contraction for the ship would mean by the time say it arrived at Proxima Centauri it would of aged differently and moved through a shorter space than it would appear to you as an observer who is relatively stationary on Earth.
 
  • #9
Galron said:
If you started out from Earth using an ion drive that slowly increased acceleration given enough time it would reach .99c.

It wouldn't matter if it increased its acceleration, it just needs to have a constant acceleration but there are problems with this:

A) Supplying it with enough fuel to get to 0.99c - taking a http://en.wikipedia.org/wiki/VASIMR" [Broken] as the best speculative ion drive with a specific impulse of 30,000 seconds you would need ~1000 parts kg fuel for every 1kg of ship

B) Having enough thrust to reach 0.99c in a reasonable time - taking VASIMR again if we assume a 1 tonne ship with 1000 tonnes of fuel then with a thrust of http://en.wikipedia.org/wiki/Ion_thruster#Comparisons" the ship will be capable of an average acceleration of 1e-6 and would reach 0.99c in roughly a million years.

C) All the other engineering issues of energy, waste heat etc

Galron said:
You have to also remember time dilation and length contraction for the ship would mean by the time say it arrived at Proxima Centauri it would of aged differently and moved through a shorter space than it would appear to you as an observer who is relatively stationary on Earth.

What do you mean move through a shorter space? From all reference frames the ship would have traveled the same distance.
 
Last edited by a moderator:
  • #10
ryan_m_b said:
It is. From the perspective of the guy on the ship the speck is traveling at 0.99c, the speck sees the ship doing the same. The energy is the result of the kinetic energy that would be the same regardless of who was traveling at that speed.

However only one of them is experiencing time dilation because one of them has been in an accelerating reference frame and the other in an inertial.

This isn't quite true. Each would perceive time for the other running slow, while the ship is in motion. What is true is that when the ship is co-moving again with typical stars again, it will have aged less, and the rocket and a nearby planetary observer agree on this. A good terminology for this is time dilation (relative) versus differential aging (invariant).
 
  • #11
PAllen said:
This isn't quite true. Each would perceive time for the other running slow, while the ship is in motion. What is true is that when the ship is co-moving again with typical stars again, it will have aged less, and the rocket and a nearby planetary observer agree on this.

Yeah I get this, what was wrong with my explanation? (Not criticising, genuinely interested).
 
  • #12
ryan_m_b said:
Yeah I get this, what was wrong with my explanation? (Not criticising, genuinely interested).

You said: "However only one of them is experiencing time dilation ". That is misleading.

Also, it is, in fact true, that:

- while moving, the ship perceives the distance to a star as much smaller than appeared before they were up to speed (length contraction; which is why they still measure light from the star as moving at c: shorter distance, smaller elapsed time, compared to Earth bound measurement of lightspeed from the star).

- If you introduce a concept of odometer, there is a perfect symmetry between length and time. Time dilation is relative and once to equivalent clocks are comoving, their rates are the same, but their accumulated time reflects their path through spacetime. Similarly, length contraction is relative, but an odometer measuring integral of apparent distance traveled will be remain different and dependent on path through spacetime. The rocket will perceive it never traveled faster than c, and that it traveled 10 light years in one year because its odometer says it really only traveled e.g. .9 light years.
 
Last edited:
  • #13
PAllen said:
You said: "However only one of them is experiencing time dilation ". That is misleading.

I see, of course. I should have explained my point more. Thanks.
 
  • #14
ryan_m_b said:
It is. From the perspective of the guy on the ship the speck is traveling at 0.99c, the speck sees the ship doing the same. The energy is the result of the kinetic energy that would be the same regardless of who was traveling at that speed.

However only one of them is experiencing time dilation because one of them has been in an accelerating reference frame and the other in an inertial.

I wasn't talking about the time dilation, but the "20 megaton bombs." At one speed you get hit by them, and at another you don't. This seems to me to point to a "proper speed of the universe"
 
  • #15
Algr said:
I wasn't talking about the time dilation, but the "20 megaton bombs." At one speed you get hit by them, and at another you don't. This seems to me to point to a "proper speed of the universe"

I don't really see why. The energy has nothing to do with time dilation or relativity, it's simply kinetic energy.
 
  • #16
Algr said:
I wasn't talking about the time dilation, but the "20 megaton bombs." At one speed you get hit by them, and at another you don't. This seems to me to point to a "proper speed of the universe"

No, ryan_m_b is completely correct. Speck says rocket moving very fast, hits hard; rocket says speck moving very fast, hits hard.

There is, of course, a frame for any region of space such that the total momentum of matter is zero, and one may describe speed in that frame as speed relative to average matter of the region. However, that is completely irrelevant to the principle of relativity.
 
  • #17
So there are no galaxies headed for Earth at 99% the speed of light? And no particles? It would only be space ships?
 
  • #18
Algr said:
So there are no galaxies headed for Earth at 99% the speed of light? And no particles? It would only be space ships?

Most likely, it will be nothing ever.

[Edit: missed the reference to particles. Particles hit Earth every day with .9999999c. They are called cosmic rays. Occasionally, they are so energetic that one proton carries as much KE as a thrown baseball.

If a 1 gram object had the speed of the fastest cosmic rays, it would hit Earth with an energy of about 1 hundred million gigatons of TNT
]
 
Last edited:
  • #19
PAllen said:
[Edit: missed the reference to particles. Particles hit Earth every day with .9999999c. They are called cosmic rays. Occasionally, they are so energetic that one proton carries as much KE as a thrown baseball.

If a 1 gram object had the speed of the fastest cosmic rays, it would hit Earth with an energy of about 1 hundred million gigatons of TNT
]
For Q1 and Q2 below, imagine two objects traveling on a perfect head-to-head collision course.

Q1. Is it possible to calculate the energy released if two 1,0 gram objects, each traveling with the speed of the fastest cosmic rays, would hit each other?

Q2. What would happened if two 1 gram objects, one traveling with the speed of .9999999c and the other at 1c, would colide with each other? Is it possible to calculate the released energy in this impact?

Thanks :)
 
Last edited:
  • #20
Lucutus said:
For Q1 and Q2 below, imagine two objects traveling on a perfect head-to-head collision course.

Q1. Is it possible to calculate the energy released if two 1,0 gram objects, each traveling with the speed of the fastest cosmic rays, would hit each other?

Q2. What would happened if two 1 gram objects, one traveling with the speed of .9999999c and the other at 1c, would colide with each other? Is it possible to calculate the released energy in this impact?

Thanks :)

I'm pretty sure (but not absolutely sure) you could just calculate the energy by each and add it up. So;

1 gram object traveling at 0.9999999c (299792428m/sec) would release 44,937,749,943,067.6 joules of energy or ~45 petajoules. So the collision of two grams would be ~90 petajoules
 
  • #21
ryan_m_b said:
I'm pretty sure (but not absolutely sure) you could just calculate the energy by each and add it up. So;

1 gram object traveling at 0.9999999c (299792428m/sec) would release 44,937,749,943,067.6 joules of energy or ~45 petajoules. So the collision of two grams would be ~90 petajoules

I used a joule to kiloton converter on the internet, if this converter is true the combined force would be about 21,48 kilotons.What about Q2? Is it possible to calculate the energy if one of the two one gram objects were traveling at 1c, and the other 1 gram object were traveling at 0,999999c?

And, finally, my Q3 =)
Is it possible to calculate the energy of a collision if both 1 grams objects were traveling at 1c?

I ask these Q2 and Q3 because I have a vaguely memory that I read that calculations states that the energy would be infinitive when reaching 1c. Or is it only the energy needed to accelerate an object two 1c that becomes infinitive?

Best regards
Mattias
 
  • #22
I know that your goal is speed; but what about slow and steady?
What if Helium 3 could be used as a fuel source, and plotting courses to moons with robotic mining missions that would set up robotic mining colonies - no humans. These "colonies" would be the galaxtic "gas stations" for future missions when technology has caught up to speed (pardon the pun) to possibly carry humans :)
 
  • #23
Lucutus said:
I ask these Q2 and Q3 because I have a vaguely memory that I read that calculations states that the energy would be infinitive when reaching 1c. Or is it only the energy needed to accelerate an object two 1c that becomes infinitive?

Best regards
Mattias

It takes infinite energy to accelerate an object with mass to c.
Maximilan said:
I know that your goal is speed; but what about slow and steady?
What if Helium 3 could be used as a fuel source, and plotting courses to moons with robotic mining missions that would set up robotic mining colonies - no humans. These "colonies" would be the galaxtic "gas stations" for future missions when technology has caught up to speed (pardon the pun) to possibly carry humans :)

You've done the hard part, coming up with the idea, now just to solve the easy part, the engineering!

That's a little bit of sarcasm there because without overcoming the huge technical hurdles ideas like this are just interesting fantasies.
 
  • #24
ryan_m_b said:
You've done the hard part, coming up with the idea, now just to solve the easy part, the engineering!

That's a little bit of sarcasm there because without overcoming the huge technical hurdles ideas like this are just interesting fantasies.

LOL .. yeah, I was trying to blend in so I could ask a Sci-Fi question :)

But nations are seriously considering this in the near future: http://www.explainingthefuture.com/helium3.html
 
  • #25
Maximilan said:
LOL .. yeah, I was trying to blend in so I could ask a Sci-Fi question :)

But nations are seriously considering this in the near future: http://www.explainingthefuture.com/helium3.html

Lol, first show me working fusion on the ground, then show me a working http://en.wikipedia.org/wiki/Fusion_power#D-3He_fuel_cycle", then show me a nuclear fusion propulsion system. After all of that let's examine the geopolitical, socioeconomic and scientific/technological situation at that point in history and then we can have a meaningful discussion about He3 mining.

I don't mean to sound flippant but discussing the role of He3 mining in future space exploration is not just putting the cart before the horse its putting the cart before the wheel.
 
Last edited by a moderator:
  • #26
ryan_m_b said:
Lol, first show me working fusion on the ground, then show me a working http://en.wikipedia.org/wiki/Fusion_power#D-3He_fuel_cycle", then show me a nuclear fusion propulsion system. After all of that let's examine the geopolitical, socioeconomic and scientific/technological situation at that point in history and then we can have a meaningful discussion about He3 mining.

I don't mean to sound flippant but discussing the role of He3 mining in future space exploration is not just putting the cart before the horse its putting the cart before the wheel.

http://fti.neep.wisc.edu/pdf/wcsar9304-1.pdf

http://www.lpi.usra.edu/decadal/leag/DecadalHelium3.pdf

Prototype Reactor:
"A commercial fusion reactor has never been built, but a prototype called the International Thermonuclear Experimental Reactor (ITER) has just begun construction in Cadarache, France. The plan is to generate the needed 100 million degree plasma by the year 2016, but a power plant that can supply electricity might not come online for another 20 years after that." reported by msnbc.com http://www.msnbc.msn.com/id/2617994...-science/t/how-moon-rocks-could-power-future/

Fusion Propulsion:
"Fusion is the only option that potentially achieves the most important regime for Solar-System travel: exhaust velocities of 105 to 106 m/s at thrust-to-weight ratios of 10-3. Such levels of performance allow both fast human transport and efficient cargo transport. There is no doubt that one of the most difficult problems that a peaceful world will face in the 21st century will be to secure an adequate, safe, clean, and economical source of energy. Existence of lunar helium-3, to be used as fuel for fusion reactors, is well documented; verified from numerous Apollo and Luna mission samples, current analyses indicate that there are at least 1 million tonnes embedded in the lunar surface. The helium-3 would be used as fuel for fusion reactors." Fusion Technology Institute of Wisconsin http://fti.neep.wisc.edu/research/dhe3

Robotic Mining Technology:
http://technology.infomine.com/robomine/
 
Last edited by a moderator:
  • #27
I should have been clearer, I meant fully mature technology or peer-reviewed research, not mission statements or opinion pieces. I'm well aware of the current state of projects like ITER but that is a far cry from even being proof of principle of what you have described.

Yes He3 is on the moon and yes there are large quantities but without fully realized technology we cannot meaningfully discuss the situation. We cannot examine the economical viability of mining without knowing exactly how much the efforts will cost, what the alternatives will be and what political and social factors will be in play. Looking at what we do know I am sceptical that anyone will make the effort to mine He3 for nuclear fusion fuel, the aforementioned first generation nuclear fusion reactors (based on ITER if it is a success) can be used to breed He3. I doubt we will ever get to the stage where sending vast robotic industries to the moon and other bodies is cheaper than simply having a number of dedicated 1stgen fusion reactors for breeding on Earth.
 
Last edited:
  • #28
Maximilan said:
...but a power plant that can supply electricity might not come online for another 20 years after that...

:rofl: Our fathers and grandfathers said the same thing in the 1940's, but every time we get a little closer we find another very complex unanticipated collective phenomenon that makes it more difficult than we thought. I think our great great grandchildren would agree that fusion almost certainly will not play a significant role in the future of power generation, instead we will refine other, more elegant approaches.
 
  • #29
JeffKoch said:
:rofl: Our fathers and grandfathers said the same thing in the 1940's, but every time we get a little closer we find another very complex unanticipated collective phenomenon that makes it more difficult than we thought. I think our great great grandchildren would agree that fusion almost certainly will not play a significant role in the future of power generation, instead we will refine other, more elegant approaches.

I disagree. We have made steady progress for the last 60+ years in confinement time and power using multiple confinement methods. Saying that it will never be a source of significant power generation seems to imply that we haven't made any progress. (to me at least) While it might not be a NEAR future approach, I have very little doubt that we will eventually reach power production.

Lucutus said:
What about Q2? Is it possible to calculate the energy if one of the two one gram objects were traveling at 1c, and the other 1 gram object were traveling at 0,999999c?

And, finally, my Q3 =)
Is it possible to calculate the energy of a collision if both 1 grams objects were traveling at 1c?

I ask these Q2 and Q3 because I have a vaguely memory that I read that calculations states that the energy would be infinitive when reaching 1c. Or is it only the energy needed to accelerate an object two 1c that becomes infinitive?

As has been said, getting to 1c is impossible. No matter how much energy you poured into an object, it would not approach c. However it's momentum would approach huge amounts near 1c.
 
  • #30
JeffKoch said:
:rofl: Our fathers and grandfathers said the same thing in the 1940's, but every time we get a little closer we find another very complex unanticipated collective phenomenon that makes it more difficult than we thought. I think our great great grandchildren would agree that fusion almost certainly will not play a significant role in the future of power generation, instead we will refine other, more elegant approaches.

WOW! Your grandpa knew about Helium 3 fusion prototypes being built before even Nuclear was on the block? Einstein must have been jealous. PLUS you got a time machine! Dang you da man - let me guess your ancestors were from Nibiru right?
 
  • #31
ryan_m_b said:
You've done the hard part, coming up with the idea, now just to solve the easy part, the engineering!

That's a little bit of sarcasm there because without overcoming the huge technical hurdles ideas like this are just interesting fantasies.

Hey don't forget that interesting fantasies are how we get the ideas for progress! If nobody ever had big dreams like that then we're not ever going to have that. No one woke up one day with some crazy new advanced concept they completely understood it and knew exactly how to prove it. That being said I'm going to go ahead and say mining the moon is probably a very very bad idea and that should most certainly not be our goal for mining extra terrestrial material.

JeffKoch said:
:rofl: Our fathers and grandfathers said the same thing in the 1940's, but every time we get a little closer we find another very complex unanticipated collective phenomenon that makes it more difficult than we thought. I think our great great grandchildren would agree that fusion almost certainly will not play a significant role in the future of power generation, instead we will refine other, more elegant approaches.

Actually our fathers and grandfathers were all about fission. Fusion is a little newer than that. And I disagree I think fusion is probably going to be used unless we skip over it to something more efficient, but even then fusion energy will likely eventually be used as the cheap alternative for the poor people.

Maximilan said:
let me guess your ancestors were from Nibiru right?

:rofl: Awesome reference that made me crack up!
 
  • #32
Monsterleg said:
Hey don't forget that interesting fantasies are how we get the ideas for progress! If nobody ever had big dreams like that then we're not ever going to have that. No one woke up one day with some crazy new advanced concept they completely understood it and knew exactly how to prove it. That being said I'm going to go ahead and say mining the moon is probably a very very bad idea and that should most certainly not be our goal for mining extra terrestrial material.

No offence but I am always surprised when people feel the need to say this. Ideas like this are always long term goals needing huge amounts of work in a variety of fields to even assess properly, which is fine as long as the limitations are realized and discussed. More often or not people simply propose 'fantastic answer X' and discuss the ramifications rather than the necessities of that idea.

Using your example yes; no one ever does wake up with a fully formed idea but once they have one they work out what all the known hurdles are, work out the hurdles of those hurdles and then set to work discussing the issue with as much information as possible. There is a big difference in discussing the feasibility of an idea and proposing it when there is no proper basis to be discussed.
 
Last edited:
  • #33
Monsterleg said:
Hey don't forget that interesting fantasies are how we get the ideas for progress! If nobody ever had big dreams like that then we're not ever going to have that. No one woke up one day with some crazy new advanced concept they completely understood it and knew exactly how to prove it. That being said I'm going to go ahead and say mining the moon is probably a very very bad idea and that should most certainly not be our goal for mining extra terrestrial material.

I'm with Ryan on this one. It is exceedingly rare for something like this to happen, where someone just wakes up with an idea. The overwhelmingly vast majority of technolgical and scientific advances are a direct result of people working in a related field or on a specific problem. There are thousands if not millions of "concepts" of things that might be that people have every day. It is only when the applicable technologies are invented or improved that these things become feasible.
 
  • #34
Drakkith said:
I disagree. We have made steady progress for the last 60+ years in confinement time and power using multiple confinement methods. Saying that it will never be a source of significant power generation seems to imply that we haven't made any progress. (to me at least) While it might not be a NEAR future approach, I have very little doubt that we will eventually reach power production.

No, that certainly does not say that we have not made progress, it's patently obvious that we have made progress. The problem is that progress towards what we thought would be sufficient is never enough, the goal keeps moving farther back. So what seems like five yards forward winds up being one yard once we've run the five yards, moved the end zone back, and rescaled the field (analogy made explicit for the adolescents in the thread above). This has been going on for 60+ years, and this is just to reach a breakeven level at enormous expense - economical power production, competing with other established approaches including fission, is orders of magnitude harder than that. This is why I do not believe it will ever compete - there are many other lines of research, for example into efficient energy storage in batteries, that should have higher priority if providing electrical power to people is really the goal.
 
  • #35
JeffKoch said:
No, that certainly does not say that we have not made progress, it's patently obvious that we have made progress. The problem is that progress towards what we thought would be sufficient is never enough, the goal keeps moving farther back. So what seems like five yards forward winds up being one yard once we've run the five yards, moved the end zone back, and rescaled the field (analogy made explicit for the adolescents in the thread above). This has been going on for 60+ years, and this is just to reach a breakeven level at enormous expense - economical power production, competing with other established approaches including fission, is orders of magnitude harder than that. This is why I do not believe it will ever compete - there are many other lines of research, for example into efficient energy storage in batteries, that should have higher priority if providing electrical power to people is really the goal.

Well, this isn't the thread to debate fusion power, so all I'll say is that in my opinion we will get there and it will be competative.
 
<h2>1. Can we really achieve interstellar travel for just .99c?</h2><p>Achieving a speed of .99c (99% of the speed of light) is currently beyond our technological capabilities. However, scientists are constantly researching and developing new technologies that could potentially make interstellar travel more feasible in the future.</p><h2>2. What are some potential methods for achieving .99c?</h2><p>Some proposed methods for achieving .99c include nuclear fusion propulsion, solar sails, and antimatter propulsion. These technologies are still in the early stages of development and would require significant advancements in order to reach .99c.</p><h2>3. How long would it take to travel to another star at .99c?</h2><p>The closest star to our solar system, Proxima Centauri, is approximately 4.24 light years away. At a speed of .99c, it would take approximately 4.27 years to reach this star. However, due to the effects of time dilation, the journey would feel much shorter for the travelers.</p><h2>4. What are the potential challenges of traveling at .99c?</h2><p>Traveling at .99c would present many challenges, including the immense amount of energy required, the potential for collisions with debris in space, and the effects of time dilation on the human body. Additionally, the spacecraft would need to be designed to withstand the extreme speeds and temperatures involved.</p><h2>5. Are there any ethical concerns surrounding interstellar travel at .99c?</h2><p>There are potential ethical concerns surrounding interstellar travel at .99c, such as the impact on other life forms that may exist in space and the possibility of contaminating other planets with Earth's microbes. It is important for scientists to thoroughly consider and address these concerns before embarking on interstellar travel.</p>

1. Can we really achieve interstellar travel for just .99c?

Achieving a speed of .99c (99% of the speed of light) is currently beyond our technological capabilities. However, scientists are constantly researching and developing new technologies that could potentially make interstellar travel more feasible in the future.

2. What are some potential methods for achieving .99c?

Some proposed methods for achieving .99c include nuclear fusion propulsion, solar sails, and antimatter propulsion. These technologies are still in the early stages of development and would require significant advancements in order to reach .99c.

3. How long would it take to travel to another star at .99c?

The closest star to our solar system, Proxima Centauri, is approximately 4.24 light years away. At a speed of .99c, it would take approximately 4.27 years to reach this star. However, due to the effects of time dilation, the journey would feel much shorter for the travelers.

4. What are the potential challenges of traveling at .99c?

Traveling at .99c would present many challenges, including the immense amount of energy required, the potential for collisions with debris in space, and the effects of time dilation on the human body. Additionally, the spacecraft would need to be designed to withstand the extreme speeds and temperatures involved.

5. Are there any ethical concerns surrounding interstellar travel at .99c?

There are potential ethical concerns surrounding interstellar travel at .99c, such as the impact on other life forms that may exist in space and the possibility of contaminating other planets with Earth's microbes. It is important for scientists to thoroughly consider and address these concerns before embarking on interstellar travel.

Similar threads

  • Sci-Fi Writing and World Building
Replies
15
Views
1K
  • Science Fiction and Fantasy Media
Replies
22
Views
3K
  • Sci-Fi Writing and World Building
4
Replies
118
Views
5K
Replies
6
Views
1K
  • Aerospace Engineering
Replies
5
Views
1K
  • Sci-Fi Writing and World Building
Replies
6
Views
542
  • Sci-Fi Writing and World Building
Replies
24
Views
468
  • Special and General Relativity
Replies
12
Views
1K
  • Astronomy and Astrophysics
Replies
1
Views
4K
  • Science Fiction and Fantasy Media
Replies
15
Views
2K
Back
Top