My wife raised an interesting point about space travel.

Question

Relativity shows that we probably cannot travel the speed of light. The closest planet with life (if any) is probably many light years away. She believes that there must be some other reason why we will never come in physical contact with life outside our solar system. In other words it was never meant to be and will never happen for an unknown reason. Any thoughts on this.

Answer 1

It sounds like the concern is delving into cosmology, which is properly a religious or philosophical area.  If there is some wise force keeping intelligent species apart, then we won't necessarily have the means to reason about that scientifically.

But the issue of infection and biological contamination is pretty remote.  In practice, biological enemies have to evolve together in order to affect each other.  Aside, perhaps, from very simple agents such as prions, the majority of bacteria evolved on Earth may not have any effect upon an alien organism.  Infection is somewhat symbiotic in the sense that microbial pathogens exploit particular processes in host organisms to wreak their havoc, and those processes may be entirely different in alien hosts -- and vice versa.

Back contamination of Earth was an issue for the Apollo missions.  NASA biologists argued much as I have above, that Moon organisms (if any) would be biologically inert to Earth organisms.  But in order to placate the lay public, the semblance of a quarantine program was put into place for returning Apollo astronauts.  However, none of that was expected to have any real result.  Only after the public accepted that Apollo crews were not bringing back species-killing organisms did the quarantine measures fall by the wayside.

Answer 2

Sounds to me like a clash between science and personal beliefs. I guess we'll just have to hope for faster than light travel in the future. Which according to some experiments isn't as far fetched as it may seem.

Answer 3

just like we were never meant to fly, or talk to someone half way around the world like they were right next to us

Answer 4

Matter cannot reach c, but that doesn't mean that it cannot exceed c so long as it remains subluminal in relation to the space the matter itself inhabits.

People could also reach other star systems, even other galaxies, by either entering stasis, or increasing their velocity to a significant percentage of c, thereby slowing the rate at which time passes for them to a near stop.

Answer 5

Your wife sound like a smart woman.

The laws of physics tell us that it is impossible to travel faster than light.  There is a thing called the Mass Dilation Effect (look it up -- Wiikpedia has a good discussion) that basically says that to travel faster than light requires an infinite amount of energy -- which is impossible.

We believe the law of physics to be the same all over the universe.  The fact that we can "sense"  the other places (using radio or light telescope, or measuring sun 'wobble' -- "senses" like that) show this to be true.  If the laws were different in other parts of the universe -- we couldn't 'sense" them!

So, IF there is life on other planets around other star, then they, too, are limited by the same physical laws -- and they can't travel faster than light either!

The speed of light is 186,282 miles per second.  At our best efforts, we can only travel about 5 miler per second! At this rate, it would take us about 150,000 YEARS to get from here to the next closest star -- OR for them to come to us.  What would it take to carry enough food, water, and oxygen to keep a group of people alive for 150 thousand years?  [Sci-Fi literature is full of stories about Generation Ships]

So yes, there is a built in isolation mechanism that will prevent us from getting there unless there are some really serious changes in rocket propulsion technology.

Why is this so?  That querstion needs to be asked in the Religion or Philosophy section.  Science and religion walk hand-in-hand: Science tells us HOW something happens, religion tells us WHY.

Answer 6

Don't you have other topics to discuss with your wife?

Answer 7

Interstellar distances are just too great to cross.  Its very easy to talk about near C speeds, but the reality is that they are unobtainable. The fuel requirements are too great and traveling at those speeds generates immense levels of radiation due to impact with interstellar hydrogen molecules.  Impact with a particle the size of a grain of sand will result in a nuclear level explosion.  These are the factors that make interstellar travel impossible.  The universe doesn't "mean things to be", it simply is.  There is no MEANING other than what we ourselves imagine.  

Answer 8

We are only beginning to understand the concepts of space and time, so to say "never" is very bold.

But, let me make this argument, using today's understanding:

We cannot reach the speed of light with a vehicle, but we may be able to almost get to the speed of light.  If we were able to get a vehicle to move that fast, the occupants could travel great distances during what seems like, to them, short periods of time.  The rest of the world would grow old, in comparison.  In that case, people could travel light years away.  Only, when they returned to Earth, a lot of time would have gone by back home.

For example, let's say I jump on a spaceship and travel just under the speed of light.  I could travel, say, a thousand light years away, but it would only feel like, say, two hours to me.  However, back home (on Earth), a little more than a thousand years would have gone by.  By the time I returned home, another thousand years would have gone by.  But, I'd only have aged a few hours, after having tea with far away lifeforms.

As others have stated, we have overcome many obstacles to travel around the flat world, beyond the speed of sound, touch the moon and now Mars, and more.  Eventually, we may understand energy, space, and time enough to overcome interstellar travel.  Perhaps, others elsewhere already have done so...

Answer 9

  It is likely that technological societies like ours are very short live maybe no more then 350 to 500 years

  We have already used up about 100 years of our time.

Answer 10

Instead of traveling at the speed of light, we can distort gravity so you can make point A to point B a lot closer than they normally are.

Answer 11

space travel to other planets will not happen in this century, or millienium

Maybe in the next 100,000 years, probably closer to million

we will never reach light speed, so yes, it will take a very long time, but it is possible provide we can get past the oort cloud

great colonies of hundreds of families will have to travel, and it will not be the generation that leaves that meets the aliens it will be the generation X number of millions of years down the road.

if we dont destroy ourselves by then

but hey, maybe when we make it to mars a super superior race will see we are space worthy and assist us, or maybe we will find a ring of near instant travel to other planets buried in egypt.. who knows

Answer 12

even if you could travel at the speed of light (or faster) you couldn't get to other stars and galaxies. maybe it's possible to go to the stars that are just a few lightyears away, but not to another galaxy, because your spacecraft would get hit by things on the way. when travelling at the speed of light, a rock at the size of a marble would destroy the spacecraft.

Answer 13

Well, we will never know....

Answer 14

She raises a good point.  The length of time any given civilization can last (and send out detectable signals) is one component of the Drake equation.  The Drake equation is an attempt to determine the number of extraterrestrial civilizations that we might come in to contact with.  Unfortunately, many of the components of the Drake equation have a high uncertainty -- this is one of those such parts.  The only method we are aware of to communicate with are different forms of light waves, meaning Earth has only been sending information into space for the past 100 years or so.  So only an area that is less that 100 light years from Earth could even know we exist.  (Unless there are other technologies used for detection of civilizations that we are not aware   of).  As the Drake equation states, not only would that civilization have to be close to Earth, it would also have to have already reached at least the same level of technology as we have in order to detect our signals.

As far as tolerating alien bacteria, it is impossible to know.

Answer 15

If we humans would stop this fooling around and get serious about solving the problem of halting the aging process, or even reversing it, we wouldn't need to travel near the speed of light in order to reach the stars. We already have the technology to lay the groundwork for acheiving this, but we simply lack the will.  What if we could clone human beings, and, if necessary, transfer one's consciousness to their developing clone? What if this proved successful and could be repeated over many, many generations?  How would that change the equation governing space travel?  Eventually, we could send out into space large ships with large population of people on board to do nothing but travel and explore space.  Everything on board, including the ship itself, could be self-repairing and self-renewable.  As stated, we have the tools at hand to develop cloned animal models to test this hypothesis. We can achieve this and make it work.  If successful, and I believe there's every reason to believe that it would be, cloning humans would change everything.

If we are to truly master the universe, we must first master our own biology.

As for disease: If they (the aliens) are at least 1000 years more advanced than we, biological based disease will not be a problem for them. They will have defenses against earth bound disease as well.

See: Human Cloning Commentary

http://www.reproductivecloning.net/open/...

Biosystems as conscious holograms

http://www.emergentmind.org/PDF_files.ht...

O.A.K. Embryonic Holography

http://www.geocities.com/nwbotanicals1/o...

ENTANGLED MINDS: Extrasensory Experiences In A Quantum Reality

by Dean Radin

ISBN: 13-978-1-4165-1677-4

Answer 16

If science shows us anything, it's that 'probably can't' only lasts so long.

At one point, we probably couldn't escape Earth's gravity.  Not to mention that even IF travel at the speed of light can't be obtained, something could probably be figured out with cryogenics, or similar methods of manned flights.

"It wasn't meant to be" isn't exactly a scientific reason, nor is it a starting point for any sort of scientific debate.  Our ignorance is our only restraint.

Answer 17

I guess I have to agree with Mintman's response.  There are a lot of things that humans weren't intended to do, but that we have done anyway.

We used to think the world was flat, and that you'd fall off the edge if you went too far.  It was only because someone decided to look for the edge that we discovered the world was round.

Back then, the world being flat was accepted as truth.  Currently, relativity is accepted as truth.  Things change!

We may discover some day that our understanding of physics is fundamentally flawed.  We may figure out how us to use wormholes, or stumble upon 'transporter' technology, and won't have to travel the speed of light.  I guess my point is that we don't really know what the future holds, and it is absolutely worth continuing to explore our world.

It's possible that it was never meant to be.  It's also possible that this was God's ultimate challenge, to have his creations find each other!

Answer 18

Interstellar travel is going to be difficult, to say the least.  But i doubt running into alien bacteria is going to bother us much.  Bacteria causes disease because it has figured out how to exploit our resources.  Alien bacteria will not have evolved this ability.

The Fermi Paradox is a related issue.  Fermi asked the simple question, "Where are they?"  A back of the envelope calculation suggests that an intelligent species could colonize the galaxy in maybe 100 million years.  It sounds like a long time, but it's entirely possible that there are intelligent aliens a billion years older than we are. And, we expect that life is common.  And we don't expect to be the first intelligent life in the galaxy.

However, we do seem to be the first explosively intelligent species on Earth.  Someone had to be first.  And, it may be that interstellar travel is so expensive that we won't do it until we must.

For us, that may be in only 100 million years.  That may seem like a long time, but it isn't.  But as the Sun gets hotter, we may move the Earth to a larger orbit.  The physics is already understood, and it's a fairly small matter of technology.  And when the Sun becomes a white dwarf, we could move the Earth back in closer.  That could give us trillions of years.  Hundreds of times longer than the age of the Universe so far.  So we might have only spread to a few systems.  That could explain the Fermi paradox.

Answer 19

Too bad the Hyperdrive can't be used to prove your Wife wrong.

Answer 20

ur right. it wasnt ment to be and it never will be. At the rate out space ships go we will never find life on another planet on a manned space flight.