JohnBT
Member
When taking the really long shots...what kind of windflags should I use to read the solar wind?
John
John
Shooting in Space
- Thread starter Lucky Jim
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FireInTheHole
Member
280PLUS:
Ack math... I've had the whole summer to pickle my brains... :banghead: I'm not going to mess with this one. Interesting prob though.... might pop it on my physics teacher this fall.
Ack math... I've had the whole summer to pickle my brains... :banghead: I'm not going to mess with this one. Interesting prob though.... might pop it on my physics teacher this fall.
Smoke
Member
I am not a scientist, n do I play one on TV.
There is no air in space to provide resistance. THere is no gravity (work with me here...) Isn't the size of the object irrelevent. Wouldn't thebullet and the hapless astronaut travel at the same speed? They don't use massive rockets to move the shuttle when its up there.
Please explain this as you would to your three year old...thats my intelect level. And don't show me the math...I'm dyslexic and hated algebra.
There is no air in space to provide resistance. THere is no gravity (work with me here...) Isn't the size of the object irrelevent. Wouldn't thebullet and the hapless astronaut travel at the same speed? They don't use massive rockets to move the shuttle when its up there.
Please explain this as you would to your three year old...thats my intelect level. And don't show me the math...I'm dyslexic and hated algebra.
C.R.Sam
Moderator Emeritus
Smoke...
Try concept;
Hit 13,000 pound locomotive with a one pound hammer, see how far locomotive moves.
Not accurate but similar to 3,000,000 grain object launching 230 grain projectile.
Now if the recoil were sustained....effect would become important.
Sam
Try concept;
Hit 13,000 pound locomotive with a one pound hammer, see how far locomotive moves.
Not accurate but similar to 3,000,000 grain object launching 230 grain projectile.
Now if the recoil were sustained....effect would become important.
Sam
280PLUS - Are you thinking of the Superman character? If so, that came later.
Smoke:
Smoke:
For the most part, that's true. But there is quite a lot of air in the space of the low earth orbits the shuttles are in compared to the space between stars, for example. There is enough air resistance to degrade even the most perfect orbit over a long period of time.
Not true. Contrary to our intuition and watching the astronauts float freely in the shuttles, the gravity where the shuttle is is almost the same as when standing on earth. The thing that creates the illusion of no gravity is that the shuttle and everything in it is in "free fall". It is orbiting the earth at the speed required to keep it in orbit. In effect it is falling to the earth very rapidly, but its forward speed keeps it from actually hitting the earth. When it has fallen the distance required to hit the earth, the earth isn't there! So it keeps falling and moving forward = it's in orbit.
See Sam's good analogy. The size (actually the mass) is relevant, very relevant.
True. They use relatively small rockets to adjust the orbits and attitude, etc. The big difference is that they don't have to move the shuttle very far or very fast with those rockets. Even a small rocket like an amateur rocketeer's rocket could move the shuttle in orbit given enough time.
ShaiVong
Member
Really thin tinfoil. The same kind demos put on their heads to prevent us of the vast right wing conspiracy to read their thoughts. Damn you tinfoil!
JohnBT
Member
I gave up trying to remember the details. I knew though that the wind flags would have to be huge.
Solar wind -> 400 km/sec, but only 6 ions per cubic centimeter.
A quick Google search turned this up:
"The solar wind shapes the Earth's magnetosphere and supplies energy to its many processes. Its density at the Earth's orbit is around 6 ions per cubic centimeter--far, far less than that of the "best vacuum" obtainable in labs on Earth. The distribution of ions in the solar wind generally resembles the distribution of elements on the Sun-- mostly protons, with 5% helium and smaller fractions of oxygen and other elements. (There are electrons too, of course, counteracting the positive charge of the ions and keeping the plasma electrically neutral.) All this flows away from the Sun with a mean speed of about 400 km/sec, and as shown by the Voyager 2 space probe, this flow extends past the outermost planets, more than 30 times more distant from the Sun than Earth, and it probably continues much further than that."
Solar wind -> 400 km/sec, but only 6 ions per cubic centimeter.
A quick Google search turned this up:
"The solar wind shapes the Earth's magnetosphere and supplies energy to its many processes. Its density at the Earth's orbit is around 6 ions per cubic centimeter--far, far less than that of the "best vacuum" obtainable in labs on Earth. The distribution of ions in the solar wind generally resembles the distribution of elements on the Sun-- mostly protons, with 5% helium and smaller fractions of oxygen and other elements. (There are electrons too, of course, counteracting the positive charge of the ions and keeping the plasma electrically neutral.) All this flows away from the Sun with a mean speed of about 400 km/sec, and as shown by the Voyager 2 space probe, this flow extends past the outermost planets, more than 30 times more distant from the Sun than Earth, and it probably continues much further than that."
Billll
Member
Here's my shot at the Brainiac thing: The earliest computers had names like Eniac which was an algorythm for something involving integrated analog computing. The -iac suffix was grafted to the word 'Brain' to yield the new word 'brainiac'.
As it happens, there was a science fiction story from some time back involving a conflict between two astronauts on the moon. The baddie held the station, and had acquired the good guys .45. The good guy, knowing that the baddie was unfamiliar with firearms, stood on a low ridge, some distance out, and let the baddie empty the gun at him, then engaged the fellow in arguement for a few minutes. Now, the gun was delivering muzzle velocity of 1100 FPS, and, it turns out escape velocity from the moon is also 1100 fps. This means that objects launched from the surface at 1100 fps, in a tangential direction will go into a very low orbit. Sure enough, after a few minutes the bad guy got several slugs in the back, from his own gun! I can think of several practical reasons why this is unlikely to actually happen, but the physics is OK.
I seem to have stumbled into the Mad Scientists wing of THR. Cool!
As it happens, there was a science fiction story from some time back involving a conflict between two astronauts on the moon. The baddie held the station, and had acquired the good guys .45. The good guy, knowing that the baddie was unfamiliar with firearms, stood on a low ridge, some distance out, and let the baddie empty the gun at him, then engaged the fellow in arguement for a few minutes. Now, the gun was delivering muzzle velocity of 1100 FPS, and, it turns out escape velocity from the moon is also 1100 fps. This means that objects launched from the surface at 1100 fps, in a tangential direction will go into a very low orbit. Sure enough, after a few minutes the bad guy got several slugs in the back, from his own gun! I can think of several practical reasons why this is unlikely to actually happen, but the physics is OK.
I seem to have stumbled into the Mad Scientists wing of THR. Cool!
telomerase
Member
>I gave up trying to remember the details. I knew though that the wind flags would have to be huge.
>Solar wind -> 400 km/sec, but only 6 ions per cubic centimeter.
Solar wind is orders of magnitude less powerful than the light pressure from the Sun, so your main long-distance windage correction will be for light pressure. Search on "solar sailing" or look in your Physics book for the equation for the momentum of reflected photons; if I remember right there's about 1.4 kilowatts per square meter of photons at the Earth's orbit.
Of course you're living in a country that doesn't recognize private property rights to extraterrestiral property (with the notable exception of geostationary orbit slots), and whose government owns exactly three 1970s "manned spacecraft". So the question isn't likely to be important soon... unless some other country decides that the near-Earth asteroids might be a teensy bit more important than Saudi Arabia, and decides to use the NERVA technology that the US developed in 1965...
http://freedom.orlingrabbe.com/lfetimes/neil_armstrong.htm
>Solar wind -> 400 km/sec, but only 6 ions per cubic centimeter.
Solar wind is orders of magnitude less powerful than the light pressure from the Sun, so your main long-distance windage correction will be for light pressure. Search on "solar sailing" or look in your Physics book for the equation for the momentum of reflected photons; if I remember right there's about 1.4 kilowatts per square meter of photons at the Earth's orbit.
Of course you're living in a country that doesn't recognize private property rights to extraterrestiral property (with the notable exception of geostationary orbit slots), and whose government owns exactly three 1970s "manned spacecraft". So the question isn't likely to be important soon... unless some other country decides that the near-Earth asteroids might be a teensy bit more important than Saudi Arabia, and decides to use the NERVA technology that the US developed in 1965...
http://freedom.orlingrabbe.com/lfetimes/neil_armstrong.htm
Orthonym
Member
telomerase, you sound...
grumpy? Like me?
Yes, another old Space Cadet here, also very annoyed at the way NASA has systematically sodomized any serious space development. I still get hoppin' mad when I think of that Saturn 5 lying on the ground at the Cape, covered in grackle poop!
grumpy? Like me?
Yes, another old Space Cadet here, also very annoyed at the way NASA has systematically sodomized any serious space development. I still get hoppin' mad when I think of that Saturn 5 lying on the ground at the Cape, covered in grackle poop!Andrew Wyatt
Member
Heinlein did a story where a bunch of High school kids with garands and 1911s fought nazis on the moon, and i wlawys wondered if a properly lubed for the conditions garand would work on the moon.
do they need a smaller gas port?
would you still hear the "pling"?
do they need a smaller gas port?
would you still hear the "pling"?
I don't think you'd need to do anything special, including a lube change, to the Garand or a 1911 to make them function on the moon. They should work just fine as is. The loss of 14+ PSI outside pressure is just a rounding error compared to the pressure it takes to operate the Garand. For both, it's the mass of the bolt/slide that counts. I doubt that the weight change would make much difference.
You wouldn't hear the "pling" unless the clip hit your helmet. You might, however, hear the shot. I'm not sure what it would sound like, but some of the escaping gases might make it to your helmet. It would probably be a faint "poof". Anyone standing near your muzzle would probably hear it a little louder.
Man, that sure would give a whole new dimension to "point blank range"!
You wouldn't hear the "pling" unless the clip hit your helmet. You might, however, hear the shot. I'm not sure what it would sound like, but some of the escaping gases might make it to your helmet. It would probably be a faint "poof". Anyone standing near your muzzle would probably hear it a little louder.
Man, that sure would give a whole new dimension to "point blank range"!
Phyphor
Member
Actually,
given that astronauts CAN communicate in space by touching helmets (the vibrations travel through the air in the helmets, into the hardened material in the helmets, and finally, reach the ears,) isn't it quite possible that the vibrations of your shot being fired would travel up your arm and be heard?
Obviously, it wouldn't sound the same.
given that astronauts CAN communicate in space by touching helmets (the vibrations travel through the air in the helmets, into the hardened material in the helmets, and finally, reach the ears,) isn't it quite possible that the vibrations of your shot being fired would travel up your arm and be heard?
Obviously, it wouldn't sound the same.
Possibly, but I think it would be faint sound at best since there would be a lot of soft, non-sound-conducting, material between the gun and your ears. And the sound from the gun vibrations would most likely be at a very low frequency.
Getting back to the original question -- A bullet would travel in space forever, with the liklihood that it will get pulled into a gravitational pull of a planet and even "slingshot" its way back out again until it is pulled back once againa and forever stay in an orbital path around said planet.
We know that Vic. We were talking about sound traveling through things other than air. Or sound coming from the escaping muzzle gases impinging on a suit helmet. etc.
Everytime I see the opening of Star Trek, past and present, I wonder where the "whoosh" comes from when the Enterprise goes by. I guess they needed it for effect, but it's far from what you would really hear, namely nothing.
Everytime I see the opening of Star Trek, past and present, I wonder where the "whoosh" comes from when the Enterprise goes by.
I guess they needed it for effect, but it's far from what you would really hear, namely nothing.Moparmike
Member
Its the "woosh" generator. The impulse engines double as wooshers at warp. 
Lord Grey Boots
Member
The woosh generator also powers the doors on the Enterprise.
280PLUS
Member
BRAINIAC the computer,,,
came before Brainiac the evil scientist and superman arch rival??
are you sure??
now here's something that needs serious research...
oh, i just realized that GRAVITY here on earth helps control recoil, right?
so i'm going to correct myself because i now believe the tumble imparted will actually be rather rapid instead of nice and slow like i first thought
AND
does the bullet take precisely the track of initial poa or is there a variance there?
i know if we define ALL the variables it then becomes a doable problem
not by me, of course
math?? i hate math...
it would be interesting to figure it on paper and then actually try it to see how the results compare (i know, "Paper, What's paper?")
came before Brainiac the evil scientist and superman arch rival??
are you sure??
now here's something that needs serious research...
oh, i just realized that GRAVITY here on earth helps control recoil, right?
so i'm going to correct myself because i now believe the tumble imparted will actually be rather rapid instead of nice and slow like i first thought
AND
does the bullet take precisely the track of initial poa or is there a variance there?
i know if we define ALL the variables it then becomes a doable problem
not by me, of course
math?? i hate math...
it would be interesting to figure it on paper and then actually try it to see how the results compare (i know, "Paper, What's paper?")
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I just did the research for you.
Brainiac the computer was invented by Ed Berkeley in 1955. Brainiac the villain was introduced in Action Comics #242 in 1958.
Brainiac the computer was invented by Ed Berkeley in 1955. Brainiac the villain was introduced in Action Comics #242 in 1958.
MeekandMild
Member
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- Dec 25, 2002
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There are no straight lines. Larry Niven discussed this problem in his fiction book "The Integral Trees" some years ago. If you are in orbit and throw something down it will go forward, if you throw it forward it will go up, if you throw it up it wil go backwards and if you throw it back it will go down, relative to you in your orbit.
280PLUS
Member
Mal said,,
"Brainiac the computer was invented by Ed Berkeley in 1955. Brainiac the villain was introduced in Action Comics #242 in 1958."
well i'll be...
i always thought it was the other way around,,,
probably cause i saw brainiac the villian way before i ever heard of brainiac the computer
280plus was introduced to the world in the may 1957 issue...
good lord,,,i even remember the story now that i read it again...
the miniature city of kandor...wooowwwwww...talk abouta mental time warp,,,
"Brainiac the computer was invented by Ed Berkeley in 1955. Brainiac the villain was introduced in Action Comics #242 in 1958."
well i'll be...
i always thought it was the other way around,,,
probably cause i saw brainiac the villian way before i ever heard of brainiac the computer
280plus was introduced to the world in the may 1957 issue...
good lord,,,i even remember the story now that i read it again...
the miniature city of kandor...wooowwwwww...talk abouta mental time warp,,,
benEzra
Moderator Emeritus
The magnitude of the recoil impulse is not affected by gravity; gravity just gives you your grip on the ground. If you were to jump up in the air at the shooting range and fire the gun while in the air, you wouldn't tumble violently with most guns (.577 Tyrannosaurs notwithstanding), even though you would be momentarily weightless.
280PLUS
Member
yes but,,,
the pull of gravity on the mass of the gun and your arms absorbs some of that recoil energy, gravity helps pull it back down after recoil right?
in space there would be no such force, therefore all that new found energy would then be directed to the mass of the body holding the pistol
and would relate directly to how stiff you held your arms
the stiffer the hold, the faster the rotation
duh,,,i think...
the pull of gravity on the mass of the gun and your arms absorbs some of that recoil energy, gravity helps pull it back down after recoil right?
in space there would be no such force, therefore all that new found energy would then be directed to the mass of the body holding the pistol
and would relate directly to how stiff you held your arms
the stiffer the hold, the faster the rotation
duh,,,i think...
Stevie-Ray
Member
If you see the episode where they use that shot many times, where a human-like race led by Warren Stevens has taken over the Enterprise and makes it go even faster than it's maximum speed of warp 9, it makes no noise at all, as it should be. It's always been one of my favorite scenes, the big E blistering to a dot on the screen. Of course then in '79 we got the first movie where Isaac Asimov as technical consultant gave them the impression of what a ship might look like going into warp. Quite impressive at the time.
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