Space wars?!

[RealUltimatePower]

Should we (The US) put more than just recon satilites in orbit? I mean killer satelites and orbital platforms from where we can drop troops or fire Em guns into enemy territory?

[James]

That is a spooky thought. As sci-fi as this sounds, I did read something recently about killer sattelites (perhaps in this forum?). I think that the U.S. should do something beneficial to the rest of the world, not something that will alienate the other 5.7 BILLION people on the planet even more.

Your question made me think of something else - it appears that GWB, if he has his way, will have two or three more wars in the next few years, with Syria, Iran, and North Korea. If they are liberated :roll: what would be the purpose of having a space based weapons system? I can't think of anything, other than the fact that it will maintain the 20+ year lead in technology the U.S. Military enjoys over most of the world.

[RealUltimatePower]

Yea staying three steps ahead is the main reason.
I HAD another option on the poll which was "only if an adversary seeks to militarise space first" but it didn't show.

Of course the present policy of the US gov is that it is not something they wish to persue. And I mean force application from space, drop troops that kinda thing. because it isn't in our national interest. However that said USSPACECOM has plans to have the technology and research done by 2020 for such an endeavor should it be decided that it is in our interest.

[rob]

i dont think a satellite weapon will be very usalbe. have a 15 minute window then you have to wait 12 hours for it to come around again. and it is pricy.

[GazB]

And of course the little problem of the international agreements not to position weapons in space... something you'd think the US would like to keep in place considering their reliance on space based assets. If they want to start a space weapon race the easiest and most obvious targets for such weapons would be satelites... the US has the most to lose in such a race, and probably why it hasn't shown any interest in any star wars programs recently. (very simply the technology designed to shoot down ICBMs can also much more easily be used to shoot down satellites which would of course be needed by the enemies systems to shoot down your ICBMs).

[ScoutRanger]

Negative

[Beowulf]

i heard the "leopard" seal detachment is getting slots to Space Ranger School....

[RealUltimatePower]

What Tane Angle brought up is very true and reminded me of something. Obviously if we wanted killer satelites we would have a way of putting them in a Geosyncronus orbit (orbitint at the same speed that the earth turnsm, and I probably spelled it wrong).
And the idea that we'd have only a 15 min window to use them is proposterous. Obviusly there would be a network of satelites to connect people in a war room to a satelite on the opposite side of the planet.

As for troops deployed in space. They'd have to put them on a station with a rotating ring design. This would supplement centrifigal force for gravity.

[Haiw]

Geosyncronus orbit (orbitint at the same speed that the earth turnsm, and I probably spelled it wrong).

if i remember correctly its called Geostationary (never thought my geography lessons wud be of much use outside the classroom ;))

[martinexsquaddie]

ORBITING laser beams are an awfully long way off.

[Smoothie104]

We will need something to fend off the aliens when they come.

[ibstolidude]

Maybe I can get a new job as "Space Shuttle Door Gunner" then HALO my ass off the side prior to exit of the atmosphere....

[martinexsquaddie]

too late we are already here
at least my platoon sgt reckons :lol:
where the hell are you from the planet zog :lol:

[Nawlins]

We will need something to fend off the aliens when they come.

Exactly! rofl


Geosyncronus orbit (orbitint at the same speed that the earth turnsm, and I probably spelled it wrong).

if i remember correctly its called Geostationary (never thought my geography lessons wud be of much use outside the classroom )

I don't remember what the term is either, but I learned it in astronomy, not geography... and it would be very easy to do... most of the small satellites (there are hundreds of them) orbiting Earth do that on their own b/c of gravity.

[Seiyuuki]

i heard the "leopard" seal detachment is getting slots to Space Ranger School....

rofl rofl rofl rofl rofl rofl

[vryhpyammoadded]

I think for now we should stay with less grand ideas like recon and maybe kenetic weapons delivered via suborbital bombers.


http://www.boeing.com/phantom/fasst.html

http://www.boeing.com/phantom/sli.html

[a. enders]

Might have missed it.....But wasn't there a point in NATO or Geneva or something else equally silly that made it illegal to put offensive weapons in orbit?Or is my information false.Drudging up from a while back,of course.

And if it ain't.It should be.Yeah,let's sit a railgun in orbit and hold the world hostage."Hey #720,why are you outta your zone?"

Paranoia,conspiracy theory type ****,perhaps.Even probably,but we all know what they say about paranoia......*adjust aluminum foil hat for best coverage*

[GazB]

Geosyncronous and geostationary (probably spelt them both wrong but who cares) are both correct and describe an orbit height at at which the orbiting object remains over one point on the surface of the Earth. Telecommunications satelites are often put in such orbits to make the always available... who wants to have to continuously adjust their satellite dish to get sat TV all day?

"Yes, certain weapons should be in space. For example, one type of weapon in the works is a (chemical, I think) laser that is designed to hit ground targets. It can hit a a room in the center of the building, on the first floor of a multi story buidling. "

The main stumbling block behind lasers being used against ground targets is our atmosphere. In space laser are invisible, but in the atmosphere very high power lasers are badly effected by dust and foreign objects in the atmosphere. There is also the problem of divergence. If you have a laser pointer you will know the beam gets 1mm wider for every metre it travels. On a rifle at short range or to point at something on a blackboard or screen it isn't a problem, but Geosyncronous orbit is 32,000km up. Even a low Earth orbit of say 200km = 200,000m. Assuming a 1mm per metre divergence that is a 200m wide laser beam at 200km and a 32km beam from geo syncronous orbit. ie too big to target one room.

The most serious stumbling block is that any laser system you put in space will be very big and very expensive and have a limited number of shots before it needs more power. Solar power just can't provide the amount of power needed.

"But wasn't there a point in NATO or Geneva or something else equally silly that made it illegal to put offensive weapons in orbit?"

There is an international agreement not to put offensive weapons in space. The very simple reason why everyone signed it was it would be a very simple matter to launch tons of satellites with a small nuke in each. Put them near your enemies recon satellites and then blow them up.

An effect called EMP which is caused by nuclear weapons detonated in outer space would make such satellites very valuable. The Soviets developed a system called FOBS or Fractional Orbital Bombardment System based on an SS-9 ICBM. Canada and Iceland and Greenland were covered with radar and other detection equipment to look for ICBM launches from Russia or China. Launch a FOBS over the South pole and as it approaches these radar and detection systems from the south detonate it. All electrical equipment that is on will receive a huge surge of power and all the fuses will blow. Not only that radio signals are blocked for about 30mins due to the ionisation of the upper atmosphere.

The whole idea of the internet was a system of communication that was decentralised and would survive such an attack...

Needless to say you could spend trillions on new laser satellites and North Korea could spend 60 million dollars and send a satellite with a nuke on board and park it in orbit right next to your laser battle station... It might have a nuke or it might have cameras, or it might be innocent. It wouldn't need to cross orbit very often or even be very close to kill it with a nuke warhead.

(BTW the Star wars program anticipated that an X-Ray laser would be the ideal weapon for penetrating the Earths atmosphere. In tests it was found that the laser it generated (it requires a nuclear explosion to power it) wasn't nearly as powerful as they had hoped it would be and that idea has been shelved.)

[budanski]

I LIKE LASERS (http://www.spacewar.com/rayguns.html)

[Haiw]

the power problem wud seem pretty easy to solve to me; simply make it a manned space station with a nuclear reactor in it :) (or am i talkin outta my ass now?)

[Kitsune]

Geostationary orbit is 36000 km above the surface of the earth! And only directly aboce the equator. A laser that is devastating after such a distance (even if its mostly space) is not possible today. And if it would be possible, it would probably be hell of a laser... monstrous. And to get something like this up to geosync orbit...
Same goes for E/M guns. A projectile travelling at 30 km/sec (quite otimistic) would need 1000 seconds to reach earth's surface. Of course an reliable E/M gun has yet to be build...

So "killer-satelites" will have to use very low orbits...300km or so. But this is science fiction. But in 25 years it might have become true. Well...most pilots won't like the idea to be snuffed out by a laser from space...the great blue yonder might not be a good place to be anymore!

p-)

[Saranof]

Yeah, lets start another weaponrush!

[USAF G]

No we should keep our heads in the sand and let the bigger superpowers worry about whether or not someone else is already gaining that advantage. Oh wait, we are a superpower! For a second I thought we were a European country. ;)

[Saranof]

No we should keep our heads in the sand and let the bigger superpowers worry about whether or not someone else is already gaining that advantage. Oh wait, we are a superpower! For a second I thought we were a European country. ;)

Or we could put the money on helping the poor and oppressed? :)

[USAF G]

Oh, that's what all of those countries are doing :cantbeli: . I'm sure no one would try to gain a military advantage, as long as we're spending all of our money helping folks (which, by the way, the US never does) :roll:

[Saranof]

Oh, that's what all of those countries are doing :cantbeli: . I'm sure no one would try to gain a military advantage, as long as we're spending all of our money helping folks (which, by the way, the US never does) :roll:

Wich countries do this now? Tell me...are we in risk of a "spaceborn assult"? rofl

Well, I know that the US never does anything to help poor people...since the remedy for that is bombs :lol:

[USAF G]

Congratulations, you've missed my point completely. woot

[James]

Isn't a laser coming from space going to get refracted and scattered when it enters the atmosphere? How would it hit what was being aimed at on Earth? Kentucky windage?

Wouldn't solid projectiles disintegrate? Think how large the space shuttle was - the Columbia disintegrated back in February. I'm sure any projectiles will not be that large.

Just some thoughts.

[USAF G]

It really depends on the composition of said projectile. "Blooming" is ,I think, the term for the phenomenon that is expected to keep lasers from getting to the ground. The laser beam superheats the atmosphere in front of it and creates an opaque barrier which the laser cannot penetrate. I believe that particle beams are the wave of the future in that arena. I think (shrug). G

[Ratamacue]

On a somewhat related topic, it appears that defenses against lasers are already on the drawing board. http://www.space.com/businesstechnology/technology/cold_plasma_000724.html

[Haiw]

best laser defense: mirror mk 1 mod 0 :D

[Herrmannek]

Fuc* lasers

Invest in this proven tec.

http://html2.free.fr/canons/canparis/canparis1.jpg

even 1 metre of concrete or 200km of atmosphere CAN'T STOP this weapon from hiting its target with amazing acuracy.

http://html2.free.fr/canons/canparis/canparis7.jpg

Wepon of future.

[a. enders]

The Paris Gun?Or just a railroad gun?Either way,with the Paris gun,didn't it take like a week to set-up and sitght in properly?

[warchild1/27scout]

you remember who won the cold war? somebody will win the space race. it might as well be us. hey if someone else gets as much power as we do right now i garrantee they won't be as nice and pollitically correct as us. they will smash us while they thank the liberal useful idiots for trashing and tearing down our nation. we need to get rid of the far left liberals and let us americans have our country back. that would mean you howard dean and you nancy pelosi. alright i feel better now. :)

[GazB]

"you remember who won the cold war? somebody will win the space race."

The Space race was won by the Soviets already.

Regarding lasers, they are not completely hopeless, the ABL seems quite interesting and might be very useful in some situations. The intended purpose of shooting down ICBMs when they are launched seems too flawed to be sensible to me, but other uses like shooting down theatre ballistic missiles like scuds etc during a conventional war seem interesting.

"the power problem wud seem pretty easy to solve to me; simply make it a manned space station with a nuclear reactor in it "

The negative publicity over the Soviets deorbiting satellites with nuclear reactors seem to suggest that huge laser battlestations with rather large reactors would not be acceptable. (The Soviet satellites used radar to track naval forces in the worlds oceans and were designed to jettison their nuclear reactor power supplies up to a higher orbit when they failed. At least one failed to jettison its reactor and landed all over Canada... an expensive cleanup and the Soviets were given the bill.)

A laser would require very large amounts of power... rather more than most reactors can generate quickly... certainly the size of reactor you can launch into space.
The ABL is a good example... a 747 sized aircraft just to hold the targetting and power supplies for a weapon designed to melt 2-3mm of aluminium that is the side of a pressurised fuelled ICBM from 300km.

To actually kill someone you would need far more power.

The only sensible current use might be to start forest fires in an enemy country.

(During the Hearings into how Star Wars technology was progressing one scientist stated that they had a laser at a power of 10 to the power of 6 and that they thought 10 to the power of 12 would be needed to create a viable weapon for its intended purpose. To which a reporter jumped up and said that was great... they are half way there. Of course the difference between 10 to the power of 6 and 10 to the power of 12 is a million (ie 1,000,000 compared to 1,000,000,000,000)... they needed to increase the power of the weapon a million times.)

As I mentioned the biggest case against such satellites is the possibility that an enemy can simply place a weapon in a similar orbit. A 30kg 152mm artillery shell can contain a 2KT nuclear warhead. It currently costs about $8,000 US per kg to launch things into orbit, so for less than a million dollars you could take out trillions of dollars worth of military and trillions of dollars more worth of communications satellites literally in one flash.

[SABER 2-3]

Of course we need orbiting stations on our outer most perimeter!!! Have you all forgotten that there is a certain highly motivated Martian (complete w/ plasma ray and pellet to goons w/ water) who is trying to blow the Earth to smithereeeeens!!! Currently the only thing stopping Marvin is a highly resourceful operator disguised as a wabbit. As a Global community and mutual target we must demand that the Alan Parsons Project be green lighted. France your gonna have to fight too; surrendering is not an option this time.

[Herrmannek]

The Paris Gun?Or just a railroad gun?Either way,with the Paris gun,didn't it take like a week to set-up and sitght in properly?

Yes PARIS GUN 1:0 for you



One thing more: puting into space a wepon scares me, what would hapen if some crazy Alibaba take over this "mighty" wepon & start to make holes in some important places, ie: GWB limo.

[GazB]

Actually starting development of space based weapons might have one good feature.

According to most historians it has been impacts from space that has wiped out many species though the billions of years of lifes existance here on earth. Survival of the fittest doesn't mean survival of the strongest... there is no way a mammal is stronger than a T-Rex. Survival of the fittest means that if an animal is perfectly adapted to its environment then it is more likely to survive. Of course if something changes that environment then survival chances plummet... like humans changing the environemtn by chopping down forests, or a bloody huge piece of rock hitting the earth at 30km/s.

Currently we have no way of stopping a mountain sized or bigger rock from hitting the earth. A nuclear explosion would just mean we get hit by a super shotgun blast of radioactive rock... the Earths gravity ensuring it will largely still hit us ayway. This is all assuming we see it coming.

At the speed it comes in even normal rock impacts with the force of an equal weight of TNT. So 1 kg of rock = 1 kg of TNT. A rock the size of a mountain might weigh 1 billion tons... 1,000 megatons. If it is a mountain or iron or something heavier then we are in real trouble...

[a. enders]

Thinking too hard,boys.Drop a chunk of steel satellite crap from geosychronous and you have a nuke-sized boom with no fallout.

[Desert-Fox]

wouldnt all this space crap (which would probably never be actually used)
cost billions upon billions upon billions of dollars for american taxpayers!

[GazB]

"Thinking too hard,boys.Drop a chunk of steel satellite crap from geosychronous and you have a nuke-sized boom with no fallout."

Umm, no. Satellites travel at orbital speed... about 11km/s. Rocks from space can and often are traveling much faster... at least 30km/s.

Also our rocket power is not very impressive so most satellites are 1 ton or less. Even if you accelerated them to travel three times faster than they already travel (which in itself would make them leave Earths orbit forever) and direct them to hit a point on earth then the impact force would be equal to a relatively heavy aerial bomb... in the 1,000-2,000kg range. By comparison the MOAB was about 9,000kgs and British heavy bombs used during WWII against Nazi sub pens were about 12,000kgs. The energy expended to get the satellite to the speed necessary would be more than was used to get take men to the moon.

"wouldnt all this space crap (which would probably never be actually used)
cost billions upon billions upon billions of dollars for american taxpayers!"

Yup, but odds are that within a few hundred years a large object will hit the Earth and do some serious damage. If we can't live in space, on the moon or Mars by then it might be all over for us. The asteroid that wiped out the dinosaurs did us a big favour... we wouldn't have beome the dominant species without it. The next impact will not do us any favours at all. Our ability to survive might just be based on our ability to avoid it by being spread around the place...

Those billions of dollars spend on research will no doubt lead to improving technologies in many ways and the investment will not doubt be returned in many ways.

[Herrmannek]

"wouldnt all this space crap (which would probably never be actually used)
cost billions upon billions upon billions of dollars for american taxpayers!"

Yup, but odds are that within a few hundred years a large object will hit the Earth and do some serious damage. If we can't live in space, on the moon or Mars by then it might be all over for us. The asteroid that wiped out the dinosaurs did us a big favour... we wouldn't have beome the dominant species without it. The next impact will not do us any favours at all. Our ability to survive might just be based on our ability to avoid it by being spread around the place...



Pesimism is the best wepon of $uckers, didn't hit for few milions why do you think it will blow in few hundreds(Yes. I know that space crap still falling, but im talking about huge game & statistic, nuclear war is more sure that crap from space i think :)

[Seraphim]

"wouldnt all this space crap (which would probably never be actually used)
cost billions upon billions upon billions of dollars for american taxpayers!"

Yup, but odds are that within a few hundred years a large object will hit the Earth and do some serious damage. If we can't live in space, on the moon or Mars by then it might be all over for us. The asteroid that wiped out the dinosaurs did us a big favour... we wouldn't have beome the dominant species without it. The next impact will not do us any favours at all. Our ability to survive might just be based on our ability to avoid it by being spread around the place...



Pesimism is the best wepon of $uckers, didn't hit for few milions why do you think it will blow in few hundreds(Yes. I know that space crap still falling, but im talking about huge game & statistic, nuclear war is more sure that crap from space i think :)

The point made by GazB is that it will happen.
They do have a tracking system to monitor objects in space. I remember they had an estimate a few months back of when there would be a good chance that a large asteroid would come near or hit earth.

The asteroid doesnt need to be any bigger than 5km to cause widespread global mortality. Even a 1km asteroid can do the same damage as a 5km one...it depends on the composition of the asteroid.

[Herrmannek]

The point made by GazB is that it will happen.


Few questions:

i) Who said that it will happen(not including UCT_Sinasta & GazB)?

ii) Even someone said that, Did he've seen a ~5km rock traveling hundred years away from earth in it direction.

iii)Or maybe that guys just said: We reject hypothesis H_0: in few hundred years ~5km rock will not hit the ground in favour of H_1: Alternative: in few hundred years ~5km rock will hit the ground at Significance Level = 0.015, so we can suggests that the alternative hypothesis H_1 may be true.

[Seraphim]

Question 1 - NASA JPL

Question 2...if Im reading it right - Near Earth Object Program

[Herrmannek]

NASA NEO Program
http://neo.jpl.nasa.gov/neo/target.html



On a daily basis, about one hundred tons of interplanetary material drifts down to the Earth's surface. Most of the smallest interplanetary particles that reach the Earth's surface are the tiny dust particles that are released by comets as their ices vaporize in the solar neighborhood. The vast majority of the larger interplanetary material that reaches the Earth's surface originates as the collision fragments of asteroids that have run into one another some eons ago.
With an average interval of about 100 years, rocky or iron asteroids larger than about 50 meters would be expected to reach the Earth's surface and cause local disasters or produce the tidal waves that can inundate low lying coastal areas. On an average of every few hundred thousand years or so, asteroids larger than a kilometer could cause global disasters. In this case, the impact debris would spread throughout the Earth's atmosphere so that plant life would suffer from acid rain, partial blocking of sunlight, and from the firestorms resulting from heated impact debris raining back down upon the Earth's surface. Since their orbital paths often cross that of the Earth, collisions with near-Earth objects have occurred in the past and we should remain alert to the possibility of future close Earth approaches. It seems prudent to mount efforts to discover and study these objects, to characterize their sizes, compositions and structures and to keep an eye upon their future trajectories.

Because of the ongoing search efforts to find nearly all the large NEOs, objects will occasionally be found to be on very close Earth approaching trajectories. Great care must then be taken to verify any Earth collision predictions that are made. Given the extremely unlikely nature of such a collision, almost all of these predictions will turn out to be false alarms. However, if an object is verified to be on an Earth colliding trajectory, it seems likely that this collision possibility will be known several years prior to the actual event. Given several years warning time, existing technology could be used to deflect the threatening object away from Earth. The key point in this mitigation process is to find the threatening object years ahead of time so that an orderly international campaign can be mounted to send spacecraft to the threatening object. One of the techniques suggested for deflecting an asteroid includes nuclear fusion weapons set off above the surface to slightly change the asteroid's velocity without fracturing it. High speed neutrons from the explosion would irradiate a shell of material on the surface of the asteroid facing the explosion. The material in this surface shell would then expand and blow off, thus producing a recoil upon the asteroid itself. A very modest velocity change in the asteroid's motion (only a few millimeters per second), acting over several years, can cause the asteroid to miss the Earth entirely. However, the trick is to gently nudge the asteroid out of harm's way and not to blow it up. This latter option, though popular in the movies, only creates a bigger problem when all the pieces encounter the Earth. Another option that has been discussed includes the establishment of large solar sails on a small threatening object so that the pressure of sunlight could eventually redirect the object away from its predicted Earth collision.

No one should be overly concerned about an Earth impact of an asteroid or comet. The threat to any one person from auto accidents, disease, other natural disasters and a variety of other problems is much higher than the threat from NEOs. Over long periods of time, however, the chances of the Earth being impacted are not negligible so that some form of NEO insurance is warranted. At the moment, our best insurance rests with the NEO scientists and their efforts to first find these objects and then track their motions into the future. We need to first find them, then keep an eye on them.


Like you se no one says it will hit within 100 years for sure, There is used term average.

No one've seen piece of rock with will hit the earth for sure. For now.

Mass scale destructions in theory have at least few hundred thousand years intervals.

So what is bigest worry, space rocks or nukes?

[Herrmannek]

But risk is so small, that there is no case. If you like spend money on big toys spend them, but don't spread panic, disinform & don't make stupid movies like "carmagedon", "day of impact", "tycho..." (if someone from HOLIWOOD reads this forum this tip is for free)

[Seraphim]

I never said it will happen in a 100years....read my posts.

[Seraphim]

Regarding the nuclear blast from an asteroid, a small one detonated over Russia in I believe the early 1900s. Wipe out all life for miles around. Also, look around, craters from ELEs are all around. There is a huge one in Ireland, one in the Gulf of Mexico (that is effectively one of the largest craters around), Meteor Lake, etc. Life on Earth has been wiped out/nearly wiped out several times. NASA said something about 12-14 times so far, at least, probably. Just some thoughts...

Or was that asteroid a UFO?
;)

Dont flame me...Im just joking around. :lol:

[Herrmannek]

Directly not but you called GazB's post...so...nevermind...

Did you knew that eventualy even moon will fall on earth so be prepared ;)

[GazB]

"Did you knew that eventualy even moon will fall on earth so be prepared"

Actually no, the moon is moving away from the Earth, not toward it... which might be just as bad. Although its most obvious role is to create tides it may also help keep the Earth on a balnced axial tilt. The magnetic pole moves quite a bit, but the rotational pole doesn't move at all, thanks to the influence of the moon. If the moon were taken away, or in this case moved away then the rotational axis would be free to move... if it ever got into a position where it pointed twoard the sun then half the planet would be continually heated by the sun, while the dark side would cool to a temperature so low Methane would freeze.

"Pesimism is the best wepon of $uckers, didn't hit for few milions why do you think it will blow in few hundreds(Yes. I know that space crap still falling, but im talking about huge game & statistic, nuclear war is more sure that crap from space i think "

It is expected soon because the patterns of extinctions are clear and regular... and due.

Our water system (ie rain etc) and tectonic shifts hide all the damage that the Earth has had to endure over the 4.5 odd billion years it has been here. Look at the moon. It is covered in hits. Earth would be worse. Although our atmosphere can burn up smaller objects we are a much bigger target and our gravity is larger so we attract more objects and pull them in at higher velocities.
The "impact" over Siberia is generally believed to have been a comet... a dirty snowball. It probably detonated about 8km up in the air and light was seen as far away as London. It flattened trees over a 2,000 square kilometer area that were discovered about 20 years later when an expedition actually made it to the area to have a look. (no crater was found).

The impact that wiped out most of the large dinosaurs hit the Yucatan penninsula in Central America. It was a combination of the two worst things that could happen. A water impact is very bad due to the Tsunamis it generates (many people live within a few kms of the sea). The real problem was that where it hit was the at the delta of many rivers. The living material carried by the rivers and deposited in the sea is largely organic and forms lime deposits. At the bottom of the sea it rots. The impact threw it up into the atmosphere and it comes down in the form of acid rain.

Every extinction has resulted in the loss of about 80% of the species at the time, especially the larger animals. The result that in the intervening time other animals grow large to replace them due to lack of natural predators. (Here in New Zealand many birds gave up the ability to fly because there were few land based predators for them to fear. The Moa was a 3m tall bird much like an Emu. An enormous bird called the Haast Eagle hunted them for food but otherwise they were safe till humans arrived.)

I have read or heard a theory somewhere that shows in the suns orbit around the milkyway galaxy the sun occasionally bobs up. These movements coincide with the extinctions and it is a theory that such movements of our sun might influence the objects in the Ooert (Spelling) cloud ( which is a band of frozen rockey objects outside the orbit of Pluto and Neptune) and occasionally send objects out of position... either toward the sun or away from it, or both. Many get swallowed up by Jupiter due to its immense gravity, but as the extinctions show some still get though.
There is no reason to believe that such objects will hit Earth directly on the first pass, there is equally no reason to believe that we will get a few hundred years warning either.

Even if we had years of warning we couldn't do very much with our current level of technology. Our most powerful nuclear warhead might knock a few flakes off a 5km object but not much more. If it is on its way to hit us that will just make bits of the think that hit radioactive. Our atmosphere would make no difference to an object that size made of rock or something harder.

Unlike a nuclear war this has happened and it definitely will happen again. Of this there is no doubt. Just getting to Mars is not enough. We need SELF SUFFICIENT colonies on the Moon (its low gravity makes travel on to the other planets cheaper and easier) and at least Mars before we can consider ourselves safe from extinction. Then we can start exploiting the mineral resources of the asteroid belt and beyond.
At the moment these things are well beyond our technology, though we are ready to make the early steps.

"Like you se no one says it will hit within 100 years for sure, There is used term average. "

"On an average of every few hundred thousand years or so, asteroids larger than a kilometer could cause global disasters."

On average every few hundred thousand years on average. 65 million years ago when the last big one hit then I might say we were safe. We haven't had a global disaster sized one since... would it be safe to assume that average is so unpredictible that we might have plenty of time? When we see it coming it is too late. We are rather more the 100 years away from being able to stop a 5km object. 100 years might be long enough for use to build self sufficient bases on the Moon and Mars if we start work now.

[GazB]

BTW

What I said:

"Yup, but odds are that within a few hundred years a large object will hit the Earth and do some serious damage."


What herrmannek said:
"Pesimism is the best wepon of $uckers, didn't hit for few milions why do you think it will blow in few hundreds(Yes. I know that space crap still falling, but im talking about huge game & statistic, nuclear war is more sure that crap from space i think "

Then herrmannek quotes:
"With an average interval of about 100 years, rocky or iron asteroids larger than about 50 meters would be expected to reach the Earth's surface and cause local disasters or produce the tidal waves that can inundate low lying coastal areas. "

From NASA and Says:

"Like you se no one says it will hit within 100 years for sure, There is used term average.
No one've seen piece of rock with will hit the earth for sure. For now.
Mass scale destructions in theory have at least few hundred thousand years intervals"

Now, I think my saying that within a few hundred years that a rock will hit Earth and do some damage is not the opposite of saying:

"With an average interval of about 100 years, rocky or iron asteroids larger than about 50 meters would be expected to reach the Earth's surface and cause local disasters or produce the tidal waves that can inundate low lying coastal areas. "

So far those little rocks have been hitting isolated places like in the middle of deserts in Arizona or places so remote in Siberia that after the impact in 1908 it was more than a decade before anyone got to the site where it happened. (Braving frightening hoardes of sandflies I believe in the process). What happens if the 50m object hits the sea off Japan? What damage could a rather large Tsunami do to coastal cities there and around the Pacific. 2/3rds of the Earths surface is water so statistically it is more likely to hit water than land. What if that 50m rock hit London, or Rio Di janero (spelling)? There is currently nothing we could do about that either. Some theories about using nuclear weapons but the number of people looking for these objects is patheticly low. The first warning might be impact.

[Ballistic]

Personally, I think expansion into space is a good thing. Whether it be any form of platform from space stations to orbiting laser cannons. The further out we get from Earth the better. Maybe it's my love of Sci-Fi speaking here, but getting into space, even in little steps is one step further into something relatively unknown to the majority and something exciting for humanity. Developing things for space, whether it be weapons based or vehicular based is damn exciting stuff. The only way we can expand is by going up, and advances in this sort of technology, even though used for warfare, are a good thing.

We wont get anywhere if people whinge all the time about this and that, about how this can only be used for bad things and so forth. As free as they are to voice their opinions, think about the big picture, and not just the damned overstated "anti this and that" crap pointed at America, when they are pretty much pioneering in something not only beneficial to them, but beneficial to us all on a much broader scale. We wont get anywhere by doing nothing, I dont know about you, but I wanna see things beyond Pluto, I wanna see what else is out there and what we are really capable of. Thats how I feel anyway.

[budanski]

Well said ballistic :D

[GazB]

I agree with Ballisitic that is is exciting and certainly the direction we must take. I just think that if the US wants to take the steps alone and from a military perspective then the likelyhood of nuclear war (ie use of nuclear weapons in space escalating possibly to use on the ground of such weapons) makes it less exciting and more stressful and brinkmanship like... you know, like the cold war...

"We wont get anywhere if people whinge all the time about this and that,"

And if you are not allowed to think for yourself or even at all, you might end up somewhere you don't want to be.