2007-05-18 02:52:17 · 5 answers · asked by Nndroid 1 in Science & Mathematics ➔ Astronomy & Space
Using the space shuttle main engines to get a one kilogram space craft up to 50% the speed of light would take 3 followed by 14,476 zeroes kilograms of propellant. That is way, way more than the mass of the whole UNIVERSE! You calculate this with the rocket equation. You need the exhaust velocity of the engine. The space shuttle engines have an exhaust velocity of 4.5 kilometers per second. The speed of light is 300,000 kilometers per second, so half that is 150,000. The propellant needed to get a payload to that speed is the mass of the payload times e to the 150,000/4.5 power. That is e to the 33,333 power. "e" is the base of the natural logarithm, and is equal to about 2.7. So to get one kilogram up to 4.5 kilometers per second takes 2.7 kilograms of fuel, and to get up to twice that speed you need 2.7 * 2.7 = 15. That is more speed than you need to get to orbit, so the space shuttle needs less than 15 times its own weight in fuel to go to orbit. To get up to 33,333 times as fast, you need to multiply 2.7 times itself 33,333 times, and the number you get is more than the mass of the entire universe. This means it is absolutely, physically impossible to use conventional rockets to get any where near the speed of light.
2007-05-18 03:09:26 · answer #1 · answered by campbelp2002 7 · 2⤊ 0⤋
No amount of conventional rocket fuel will ever get a rocket anywhere close to that speed. It will take something much more powerful than a conventional rocket to get a craft anywhere close to that kind of velocity - and I would LOVE to see it happen in my lifetime.
2007-05-18 02:57:15 · answer #2 · answered by Paul Hxyz 7 · 1⤊ 0⤋
It maynot be possible at all. The conventional fuel in conventional space rocket system which may attain half the speed of light has to be the size of couple of city blocks with burn rate in terms of thousands of Mega Tonnes per second.
2007-05-18 03:05:39 · answer #3 · answered by Anonymous · 0⤊ 1⤋
You couldn't make enough standard rocket fuel for that. The closest we could get to light speed within our current technology is 10%, and it would require the use of nuclear bombs for propulsion. there actually is a 60 year old blueprint for such a vehicle...but it would have to be built in space and no one wnats to pay for such a vehicle. there's also a treaty preventing the detonation of nukes in space....personally, I can't think of a better place to detonate them!!!
2007-05-18 02:56:43 · answer #4 · answered by bradxschuman 6 · 1⤊ 0⤋
It's not about the quantity of fuel, it's the thrust acheived by the engines.
In order to reach half light you must have a thrust of half-light speed.
2007-05-18 03:21:21 · answer #5 · answered by Anonymous · 0⤊ 1⤋