Nuclear Rockets Could Shorten Flight Time to Mars
Paraphrased by Steve
Scientists are drawing
up plans for a new age of space travel, using nuclear-powered rockets
that could make it easier to carry astronauts to Mars.
The strength of nuclear propulsion is that it is more efficient than traditional chemically-propelled rockets. All rockets require fuel. Chemical rocket engines burn it, heating up the fuel and accelerating the combustion byproducts out a rocket nozzle. Nuclear thermal engines employ a very compact mass of nuclear fuel to release tremendous amounts of energy. That energy is used to heat lightweight hydrogen gas, and shoot it through a nozzle to get thrust. The nuclear reaction heats the hydrogen to much higher velocities than chemical combustion can.
O'Keefe has pointed
out that today's spacefarers travel at the same speed John Glenn did more
than 40 years ago when he became the first American to orbit the Earth.
Astronauts are among the most enthusiastic boosters for nuclear rockets. The nuclear thermal rocket has the advantage of being able to dramatically reduce trip times to and from Mars. This reduces the amount of time that astronauts are exposed to the dangerous solar and cosmic radiation that permeates space.
Compared to the radiation released from a well-designed, adequately shielded nuclear rocket engine, the radiation environment of space is tremendously more dangerous.
NASA asked last year
for funding of almost $1 billion over five years to develop nuclear rockets.