What are alternative forms of propulsion that seem viable in the near future?

Answer 1

My favorite for the last ten years has been plasma fission. Ten
years ago they developed the first 25 Tesla superconducting
magnet. Niobium-Nobelium wires in a Titanium metal shell. 25
Tesla should be enough to contain an atomic bomb explosion.
Then you take advantage of the fact that Hydrogen doesn't
ionize until 13.7 electon volts, but Plutonium ionizes at 6 electron
volts. 13.7 electron volts is 300,000 degrees Fahrenheit while
6 electron volts is 140,000 degrees Fahrenheit. So you maintain
the temperature between 140,000 degrees F. and 300,000
degrees F. and you pump hydrogen through the reactor
chamber as your exhaust gas. Each of these spacecraft would
weigh at least 100,000 tons at launch and probably 75,000 tons
upon reaching escape velocity. Each launch would send more
payload into space then has been launched in the entire history
of spaceflight. The spaceships powered by plasma fision would
be 1,000 feet long and 300 feet in diameter. They would almost
certainly have to be launched straight up from a desert region
for safety purposes. Nobody would want 80,000 tons crashing
down on then. And they probably could not be launched into
low Earth orbit for the same reason. And there would be some
radiation released into the Earth's atmosphere. But that is the
most likely way that we Earthers will colonize the solar system.

Answer 2

I assume you're speaking of propulsion in *space*.

One particular method sticks out in my mind - nuclear thermal propulsion. The idea has actually been tested. Force a fluid directly through a hot fission reactor and vent the hot gas as an exhaust.

You could also generate electricity and use it to drive the exhaust at even higher velocities...(great specific impulse numbers but lower thrust)

Unfortunately, the politics of nuclear power has prevented launching nuclear power sources using critical masses of fissile material.

Answer 3

Solar, but leave the batteries at home...Solar Sail. Huge Mylar sail, kilometers across, catch photons emitted by sun and other stars. Cheap and do-able. And you don't glow in the dark. I'm kinda nervous about launching a nuclear reactor on top of a rocket.

Answer 4

Walking

Answer 5

solar Power. We need to emphasize more utilization of solar panels, which can be used to charge up batteries for electric cars. Drive at night on the charge, and drive in the day by sunlight. Even it is is cloudy, there is enough energy in the daylight sky to power solar panels.,

Answer 6

Kudo's to Ethan for noticing the catagory this is in.

I agree with him and will add Plasma.

Answer 7

Anti-matter, which is really hard to make. If enough is made than we could be able to reach great speeds.

Answer 8

levitation. Aren't the monks claiming they have the power?

Answer 9

i prefer to answer questions about astronomy, but nasa and esa are beginning to use ion propulsion.

look here:
http://en.wikipedia.org/wiki/Ion_thruster
http://science.nasa.gov/newhome/headlines/prop06apr99_2.htm
http://www.esa.int/SPECIALS/SMART-1/SEMLB6XO4HD_0.html

Answer 10

solar wind