Manned space travel always was, and still is, a pointless project.

[gunsmith]

rocks, huge rocks that can destroy continents and virtually wipe out mammalian life.
we need to develop things to combat asteroid and comet impacts. 

[HankB]

rocks, huge rocks that can destroy continents and virtually wipe out mammalian life. we need to develop things to combat asteroid and comet impacts. 

Let's say we discover a big asteroid is going to hit us in 15 years. And let's say it will take 10 years to outfit a mission to either destroy it or nudge it out of our path.

The way NASA is run today, before beginning the actual outfitting of the mission, we'd spend 8 of the next 15 years holding hearings, deciding how to award contracts, investigating how the money is being spent, allocating funding to companies that will hire the properly diverse workforce, determining whether contractors have enough carbon credits to produce the required components, and, of course, we'd probably farm out some of the work to an international organization to foster a spirit of transnational co-operation.

Oh, and we'd have to negotiate for permission to do anything with religious zealots who believed that interfering with the asteroid would be thwarting God/Allah/Yahweh/Thor/Manitou's will.

Result?

Asteroid impact 3 years before the mission is ready. 

[AJ Dual]

The main goal, even if NASA and it's ilk aren't really addressing it is the long-term survival of the human race.

If you think our survival is important, a significant portion of our population as a species needs to be "out there", otherwise all our eggs are in one basket. Even with all the scientific evidence we now have, humans tend to have a rather myopic view of geologic time, much less just our own history on a millenial scale.

Asteroids/Comets
Ice Ages
Supervolcanisim
War
Plauge/bio-war
Technological "oopses" (run-away nanotech, malevolent AI etc.)
Natural changes in solar output or mega-flares

And the list goes on...

And even if one of those events, or some combination of them is not enough to make Earth "worse" than places like the Moon, Mars, or artificial space habitats, the technology developed to live in those places will make sheltering on a less hospitible or battered Earth childs play.

Now neither NASA or any commercial concern is doing much to attack this directly, but something is better than nothing. What little manned exploration we have is the very thin thread that holds the long-term survival of our species, our history, and our culture.

If you have a Chiliast viewpoint, or are okay with humanity having it's time, then dissapearing, then none of the above is going to matter to you. Of course, it'll suck the most for the children of the "last generation" as we go extinct. The little ones who haven't been able to enjoy the most of their lives. Although I suppose if one believes they're all going to ascend into Heaven, or Heaven will come to them, that notion does not bother you either.

And if there is a rapture or some other divine catharsis, I think an eternal, omnipotent, and all powerful God can find us on the Moon, Mars, or somewhere around Alpha Centauri if he/she/it wanted to. 

Personally, I think that the old joke of the man praying to God to rescue him from his roof in a flood applies here. The one where the man refuses several kinds of earthly rescue, and then finally drowns, and then standing before God, asking why his prayers weren't answerd, and God says: "Well, I sent you two two boats and a helicopter you dumbass..."

Science, nuclear power, rockets, etc... Those are the "two boats and a helicopter" God has given us, we're fools if we don't use them.

[ilbob]

So far manned space flight has produced almost nothing of tangible benefit to mankind, while unmanned space activity has been invaluable.

[Uncle Bubba]

There were no colonies established as a result of the treasure fleets, no trade routes opened up, no alliances formed, no enlargements of understanding among China’s educated classes. The Ming court decided, at last, that the whole business was too costly. The records of Zheng’s last two expeditions were destroyed in a court intrigue, and China commenced the retreat into incurious bureaucratic despotism from which she was awoken only 400 years later, when European traders came banging on the nation’s doors.

If you don't look outward all you do is look inward and the world passes you by, until someone who's had their head up decides to slap you in the head and take advantage of you. That's justification enough for a space program.

[Brad Johnson]

The main goal, even if NASA and it's ilk aren't really addressing it is the long-term survival of the human race.

If you think our survival is important, a significant portion of our population as a species needs to be "out there", otherwise all our eggs are in one basket. Even with all the scientific evidence we now have, humans tend to have a rather myopic view of geologic time, much less just our own history on a millenial scale.

Asteroids/Comets
Ice Ages
Supervolcanisim
War
Plauge/bio-war
Technological "oopses" (run-away nanotech, malevolent AI etc.)
Natural changes in solar output or mega-flares

Zombies.  You forgot zombies...

Brad

[S. Williamson]

Of course, all nations have pledged not to weaponize space, so we don't have to worry about that. Of course, he that holds the highest ground holds a decided advantage.

I'm personally surprised that nobody's built a space fighter yet.  There are a LOT of targets in orbit that would be devastating to lose...

[longeyes]

Unmanned speace exploration definitely makes more scientific (and economic) sense, but manned space flight appeals to our radical sense of daring and adventure and therefore has a justification of its own, not to mention that it is the ultimate Get Out of Dodge project.

[AJ Dual]

I'm personally surprised that nobody's built a space fighter yet.  There are a LOT of targets in orbit that would be devastating to lose...

There have been some attempts by the Russians. And some early work was done by the USAF as well.

Two of the Russian Saylut space stations that pre-dated Mir had 30mm'ish automatic cannon. One the cannon was axialy mounted and they manuvered the whole station with the RCS thrusters. The other was on a complex waldo-armature type arrangment. They were designed for use in case an American spysat got in close for pictures, or extreme paranoia, U.S. Astronauts made an attempt to board it. (Someone in the Kremlin watch Dr. No, IMO...)

This was when hi-rez intelligence was still returned to Earth in automated film cannisters, so shooting at a satellite made some sense.

Then as spy satellites improved, any spying satellite would be way out of range. And in terms of space warfare, it's just easier to launch a bag of sand or whatnot in a retrograde orbit, or just have a kamikaze satellite collide with the target, or detonate next to the target.  Then it just wasn't worth the mass-fraction and additional fuel to launch machineguns, nor the lost space that could be used for other useful gear etc.

They also had a prototype/mockup of a mini-shuttle armed with machineguns and missiles in the event of a Vandenburg polar launch of the Space Shuttle on a military mission during wartime, but it was never completed as well.

So none were really "fighters" per-se, they were armed stations, or an interceptor. And as far as exotic weapon systems go, it's always easier to just add more velocity. Our current ballistic missile interceptors lack warheads, it's just a collision kinetic kill weapon. The closing velocities are so high, there's no point in adding explosives. And nukes are less effective in space than one might think. Without air to translate the gamma and x-ray pulse into thermal and blast effects their destructive radius is minimized greatly, yet the "kill zone" from the radiation drops quickly.

And to manuver a lot, or have a "dogfight" it's nearly impossible, each manuver requires fuel/reaction mass. Which means big fuel tanks, then more fuel to push the fuel, then more fuel to push the fuel that pushes the fuel etc. So barring some very exotic technology, space warfare will probably be something like a large efficient carrier ship herding formations of small drones, bombs, and kinetic kill vehicles like a big game of 3D ballistic chess.

[AZRedhawk44]

And to manuver a lot, or have a "dogfight" it's nearly impossible, each manuver requires fuel/reaction mass. Which means big fuel tanks, then more fuel to push the fuel, then more fuel to push the fuel that pushes the fuel etc. So barring some very exotic technology, space warfare will probably be something like a large efficient carrier ship herding formations of small drones, bombs, and kinetic kill vehicles like a big game of 3D ballistic chess

Nah-ah...  As long as we have trillium ore and a refinery, we can keep sending out the vipers to bank and flip around, and shoot 20mm cannon shells at high rates of fire without altering our own trajectories since we have the thrusters on full burn.

And, you're forgetting Death Star lasers, too.

 

I agree... space warfare will be about chess-oriented standoffs, large battle platforms and counterexplosions to deflect enemy projectiles.  Right up until the invention of the first directed energy weapons that are worth their lift-cost to put in space.

Part of me thinks that is why we have nothing on the moon now.  We can't really defend it.  Even if we lifted an Aegis missile battery (or space equivalent) to a moon base, we could only deflect so many shots before resupply became an issue.  An Earth-based enemy has no such limitations.

Freakin' lasers on the moon, though, can be fueled by nuclear reactors or huge solar arrays.

[AJ Dual]

I agree... space warfare will be about chess-oriented standoffs, large battle platforms and counterexplosions to deflect enemy projectiles.  Right up until the invention of the first directed energy weapons that are worth their lift-cost to put in space.

Part of me thinks that is why we have nothing on the moon now.  We can't really defend it.  Even if we lifted an Aegis missile battery (or space equivalent) to a moon base, we could only deflect so many shots before resupply became an issue.  An Earth-based enemy has no such limitations.

Freakin' lasers on the moon, though, can be fueled by nuclear reactors or huge solar arrays.

Well, I think the main downside to the defenseability of the Moon is the lack of ferrous metals in it's crust compisition as compared to Earth. With helium 3 fusion potential, and week-long solar power, you could build one hell of a coilgun along a mountainside, or along crater rims, but wouldn't have much to launch from it.

And beam weapons are limited to something called Rayleigh length http://en.wikipedia.org/wiki/Rayleigh_length.

To maintain a destructive focus at the long distances of space, you're looking at extremely large emitters or mirrors to get any substantial range and still have destructive potential at more than a couple thousand miles. So I suspect even beam weapons will be mounted on the forward drones, or used as last-ditch CWIS-type applications.

One option may be fission bomb pumped x-ray lasers that close with the targets.

[makattak]

Well, I think the main downside to the defenseability of the Moon is the lack of ferrous metals in it's crust compisition as compared to Earth. With helium 3 fusion potential, and week-long solar power, you could build one hell of a coilgun along a mountainside, or along crater rims, but wouldn't have much to launch from it.

And beam weapons are limited to something called Rayleigh length http://en.wikipedia.org/wiki/Rayleigh_length.

To maintain a destructive focus at the long distances of space, you're looking at extremely large emitters or mirrors to get any substantial range and still have destructive potential at more than a couple thousand miles. So I suspect even beam weapons will be mounted on the forward drones, or used as last-ditch CWIS-type applications.

One option may be fission bomb pumped x-ray lasers that close with the targets.

Seems to me that the beam weapons would make excellent defense weapons, though.

[Viking]

Well, I think the main downside to the defenseability of the Moon is the lack of ferrous metals in it's crust compisition as compared to Earth. With helium 3 fusion potential, and week-long solar power, you could build one hell of a coilgun along a mountainside, or along crater rims, but wouldn't have much to launch from it.

Chucking rocks at high speed worked for the protagonists in The Moon Is A Harsh Mistress...

[Harold Tuttle]

[MechAg94]

So far manned space flight has produced almost nothing of tangible benefit to mankind, while unmanned space activity has been invaluable.

But can you really separate the two?  Would we have put in the same investment and such just to send unmanned rockets up? 

Either way, the original article glosses over so many things and is so full of holes it is worthless.  He complains about the cost of the space program.  If you look at the money spent compared to all the other worthless govt programs in existence, it is a drop in the bucket.  Yet the space programs have actually generated technology paybacks.  Social Security is a scam that shouldn't cost the taxpayers near what it does if it was more of a private program.  I have no problem with welfare in a limited way, but the bloated federal spending on it should go away and be left to the states to do or not do.  There are many others to a greater or lesser extent. 

On another line of thought, India recently sent a probe to orbit the moon and is considering unmanned landings or even a manned mission.  Would they be doing that if we had not set the example?  It may not be the US that opens the frontiers of space, but at least we started opening the door. 

[Reifen]

This may be a stupid question, but I'm not as up to date on this theoretical stuff as some of you.

Why not use nuclear power like we do for some of our naval vessels?  I mean it'd be a pain to get the equipment up there, but once it's there...lots and lots of power.

[makattak]

This may be a stupid question, but I'm not as up to date on this theoretical stuff as some of you.

Why not use nuclear power like we do for some of our naval vessels?  I mean it'd be a pain to get the equipment up there, but once it's there...lots and lots of power

I italicized the pertinent part of your statement. Rather than "a pain", think "cost prohibitive".

[AZRedhawk44]

I italicized the pertinent part of your statement. Rather than "a pain", think "cost prohibitive".

A few years ago (or 15 years maybe...may have been when I was in high school), NASA had plans to launch a satellite that was powered by a small nuclear reactor.

Florida went banana-flavored-apescat.

"But what if it blows up and leaks radioactive stuff on the coast or into the ocean?"

I'm sure the reactor was going to be powered off for launch and stowed in a relatively inert state, inside a shielded housing, with tracking capabilities in the event of a failed launch...

But you know how coastal elites are about windmills, oil drilling and space launches.

[Cromlech]

Perhaps if/when a 'space elevator' is built they can slowly and surely raise something like that up through the atmosphere.

[makattak]

A few years ago (or 15 years maybe...may have been when I was in high school), NASA had plans to launch a satellite that was powered by a small nuclear reactor.

Florida went banana-flavored-apescat.

"But what if it blows up and leaks radioactive stuff on the coast or into the ocean?"

I'm sure the reactor was going to be powered off for launch and stowed in a relatively inert state, inside a shielded housing, with tracking capabilities in the event of a failed launch...

But you know how coastal elites are about windmills, oil drilling and space launches.

Ahh... looks like I was wrong- not "cost-prohibitive", but NIMBY.

[Viking]

Perhaps if/when a 'space elevator' is built they can slowly and surely raise something like that up through the atmosphere.

If only we could get those pesky nano-tubes to serve as cables first...

[roo_ster]

I think some of the folks waxing eloquent over the wonderfulness of NASA and gov't-funded manned space exploration are forgetting that it is not just a matter of:
"Gov't spends big money on space, good things follow."

It is closer to:
"Gov't spends big money on space, claims right to regulate how us peons access it and erects barriers from every agency that might, possibly at some point in the future, have an hypothetical interest in the deal."

IOW, gov't has done to private space exploration what it did to cell phone technology that was ready to roll after WWII: stalled it with bureaucratic & regulatory road blocks.

[FTA84]

I think that there are many brushes to paint space technology with:

There are three categories that come to mind:

Military (Rocketry, Robotics, Avionics...) -- Technology that is politically-correct to develop under the guise of a (noble) space program.

Zero gravity research -- Items that must be developed in zero gravity.  Nasa is pretty good about funding these items correctly.  Nasa operates large drop chambers to simulate zero gravity projects, and only ones the ones that gain the most merit in the drop chambers actually make it to the shuttle.

Popular/Random -- Technologies little utilized until the space program popularized them or technologies developed to solve space problems -- but not necessarily space related.

The last ones are the ones I think that I people are willing to give up.  Money invested into anything will develop random/popular technologies (see sports equipment, race tech, ...).  I think that this is the essential problem pinning a program as good because it develops random/popular tech.  It is not known, if the money was invested in other projects , what the comparison in quantity/quality of technological yield would be.  The conversation reminds me of that game "Civilization" from the mid 90s.


I also wonder if the space program wasn't (or maybe still is) a lure for scientists to defect from other countries where they'd be put to malicious use.

[erictank]

In my eyes it serves a purpose for building up hype. OHMAHGAWD we got a man on the moon! Millions of kids think it is cool, and want to be Astronauts, and a few do become one. That's all I can think of though.

Anytime I see someone suggest that manned spaceflight is a waste or some kind of boondoggle, I'm reminded of this quote (courtesy of L. Neil Smith):

"Manned spaceflight versus robotics? Let's see ... on your wedding night, would you be satisfied to send in a remote, and receive telemetered progress reports?"

And that's BEFORE considering all the practical benefits we have or could yet realize from the space program, not excluding the ability to get all of humanity's eggs out of a single basket.

[RocketMan]

You lost me here. What does zero-G have to do with semiconductor processing?

It is/was thought to be easier to grow defect free monocrystalline compound semiconductor crystals in zero gee.  However, they do a pretty good job growing them in one gee these days.

http://en.wikipedia.org/wiki/Compound_semiconductor