How *realistic* is the goal of traveling to another solar system?

Question

Considering the closest star is about 4.2 light years away.

Answer 1

At this point in our technological development, not at all. The only way it's doable at all right now is by what's called a generation ship, so named because several generations of crew members will live and die during the voyage, with only their descendants reaching the goal star system. How it would be possible to keep a crew sane during such a mission is subject to speculation.

However, we're at an interesting place in our development. The pace of change accelerates exponentially, and we're just at the point where it's starting to really ramp upwards. To say that the stars will <forever> remain unreachable to us is, in my view, unduly pessimistic. Especially in light of the fact that the LHC is about to come on line, and, it is hoped, teach us new things about how the universe works. I think it's not unrealistic to think that, some day, humanity will reach other stars.

Answer 2

Very real, the problem is the world is not focused on traveling to the stars. "If the airplane had advanced as far-and as fast-as the computer, what would airline travel be like? Today's jumbo jet, it seems, would carry 100,000 passengers. It would fly them to the moon and back for $12.50 each"   Once life and resources are proven to exist on other worlds, things will change rapidly.

Answer 3

with our current knowledge, it's unthinkable..... we simply couldn't do it no matter what we did...

Answer 4

For you or I, it's not possible.  We could leave with enough people to make a self sufficient community in space, and in 100,000 years or so our ancestors could get there, though.

The fastest vehicle we've ever created was New Horizons, which moves at about 58,000 km/h.  4.2 light years is about 3.9 * 10^13 km.  So you're looking at about 77,000 years of travel time.

And New Horizons was a small probe.  We're talking about trying to accelerate a community-sized ship to those speeds.

That's just to get to the closest star.  What if all the interesting stuff is a lot further away?

Some people don't seem to understand that it's not a technology thing.  No amount of research is going to give us the infinite amount of thrust required to travel light speed.  I don't care how fast computers have advanced or that people in 1900 used steam engines.

Hopefully some kind of exotic alternative to just thrusting will come about, like wormholes or space compression.  I'm not betting on it though.

Answer 5

With our current technology?  Completely unrealistic, but I still think it is a better idea than having troops in Iraq.

Answer 6

I think it would be achievable soon ....

Answer 7

It's possible now. What is not possible is living through the experience or having equipment keep working for hundreds of years.

Answer 8

I'm with the physicist Brian Greene when he says that people hundreds of years ago would have considered our technology impossible. Obviously there are tremendous difficulties inherent in interstellar travel, but I don't believe that they are insurmountable. They just appear that way to us because we have not yet reached the technological level required.

In terms of how realistic it would be today, the answer is not realistic at all. We have probes on their way to other stars (Voyager 2 is heading towards Sirius, I believe) but it will take them hundreds of thousands of years, by which time they will have long exhausted their power supplies.

Answer 9

Not very, until we somehow develop a method to go faster than the speed of light. 4.2 light years does not say it all. Light is instantaneously at 186,000 miles per second, whereas with our present technology, we have to accelerate from what is essentially a standstill. This period of acceleration takes time to build up speed. Likewise, we have to decelerate to a stop at the other end. At present, if we had a power source capable of powering flight for the entire trip, we would accelerate to the half way point, flip over and decelerate to the end point. We have no engine capable of sustained thrust for that long a period because there is no way to carry enough fuel but if we did, it would be possible. Then, at the other end, you would have to locate a fuel source for the return trip, if you did not bring enough with you for the round trip. It simply is not practical with the technology we have today.  

Answer 10

What do you mean by 'realistic'?

There is no physical principle we know of that would prevent travel to other star systems. However, the great distances do introduce many problems. The fastest potentially interstellar object we have ever built, the Voyager 1 probe, is traveling at about 62100 km/h, and at that speed would take about 73000 years to reach the closest star to the Sun, Proxima Centauri. In order to reduce travel times to the level where a machine could still be operating properly to send back a signal from its destination star system, we will need to find some new method of propulsion. A number of methods have been proposed, and the most feasible are the orion drive (a drive based on exploding nuclear bombs behind a spaceship to push it forwards) and light sails (which would act like interstellar sailboats, being pushed either by the light of the Sun or by an array of lasers mounted on Earth, on the Moon or in Earth orbit). Ion drives are probably too slow, and quantum light drives might be very fast but are based on rather shaky physical principles.

Orion drives, the most effective proposition, could achieve a speed of perhaps one tenth that of light, which would cut the travel time between star systems in our galaxy to a few decades, short enough to send machines and even people from one star to another. However, building a sufficiently large orion drive ship (they have to be large in order to carry enough nuclear bombs) would be EXTREMELY expensive, and with our current technology and economy would probably take several decades and literally trillions of dollars to achieve. It will become more feasible as our space infrastructure and technology both improve, however, and if an efficient way to manufacture antimatter is discovered, that would allow us to build a far smaller ship that would cost correspondingly less (although it wouldn't be able to carry a person).

Light sail ships, in the meantime, are probably somewhat cheaper than orion drive ships, but also slower. A truly fast light sail would probably have to be built of a very thin material, and could conceivably be propelled by light bouncing off a larger, flexible mirror orbiting the Sun that would be reshaped to focus a huge amount of light on the area of the interstellar ship's sail. Light sails would also have an easier time decelerating than orion drives, because they would not need to carry any extra fuel for the purpose.

Answer 11

Very possible.  Remember 100 years ago we could not get from Denver to Phoenix in less than a couple of months or from US to to Europe without a steam engine.  It will be a while but in the future we will be living on another planet in another solar system with beings we once thought never existed.

Answer 12

It's 50/50.

Conventional knowledge is no where near being able to be used to go 4.2 light years away.

And yet the very tools we have created can also be used to create advanced star ships. So this is 50/50

as far as advanced knowings of the universe and applicable worldwide. This has not happen yet of course. If it did, there is alot of 'politics' that get in the way. It is less than a 50/50 chance for this to happen. It's more in favour of the world's control systems.

The way things are going, no one is going to see advanced understandings of the universe. Since most people scoff at the idea of higher ground...most are in disbelief that anything can be learned. Or that the timing factor is 100 years into the future. That is the big mistake...always placing your values into the future when it is the NOW which can deliver to you this higher knowledge.

It is here btw, the high knowledge! Right under your noses, but none of you are looking hard enough.