To Mars and back in 90 days?

In this artist's conception, a plasma station (lower left) applies a magnetized beam of ionized plasma to a spacecraft bound for Jupiter. (John Carscadden, University of Washington). Click here for a larger version.

In fact, with magnetized-beam plasma propulsion, or
mag-beam, quick trips to distant parts of the solar system could become
routine, said Robert Winglee, a UW Earth and space sciences professor
who is leading the project.

Currently, using conventional technology and adjusting for
the orbits of both the Earth and Mars around the sun, it would take
astronauts about 2.5 years to travel to Mars, conduct their scientific
mission and return.

"We're trying to get to Mars and back in 90 days,"
Winglee said. "Our philosophy is that, if it's going to take
two-and-a-half years, the chances of a successful mission are pretty
low."

Mag-beam is one of 12 proposals that this month began
receiving support from the National Aeronautics and Space
Administration's Institute for Advanced Concepts. Each gets $75,000 for
a six-month study to validate the concept and identify challenges in
developing it. Projects that make it through that phase are eligible
for as much as $400,000 more over two years.

Under the mag-beam concept, a space-based station would
generate a stream of magnetized ions that would interact with a
magnetic sail on a spacecraft and propel it through the solar system at
high speeds that increase with the size of the plasma beam. Winglee
estimates that a control nozzle 32 meters wide would generate a plasma
beam capable of propelling a spacecraft at 11.7 kilometers per second.
That translates to more than 26,000 miles an hour or more than 625,000
miles a day.

Mars is an average of 48 million miles from Earth, though
the distance can vary greatly depending on where the two planets are in
their orbits around the sun. At that distance, a spacecraft traveling
625,000 miles a day would take more than 76 days to get to the red
planet. But Winglee is working on ways to devise even greater speeds so
the round trip could be accomplished in three months.

"This would facilitate a permanent human presence in space" But to make such high speeds practical, another plasma
unit must be stationed on a platform at the other end of the trip to
apply brakes to the spacecraft.

"Rather than a spacecraft having to carry these big powerful propulsion units, you can have much smaller payloads," he said.

Winglee envisions units being placed around the solar system by
missions already planned by NASA. One could be used as an integral part
of a research mission to Jupiter, for instance, and then left in orbit
there when the mission is completed. Units placed farther out in the
solar system would use nuclear power to create the ionized plasma;
those closer to the sun would be able to use electricity generated by
solar panels.

The mag-beam concept grew out of an earlier effort
Winglee led to develop a system called mini-magnetospheric plasma
propulsion. In that system, a plasma bubble would be created around a
spacecraft and sail on the solar wind. The mag-beam concept removes
reliance on the solar wind, replacing it with a plasma beam that can be
controlled for strength and direction.

A mag-beam test mission could be possible within
five years if financial support remains consistent, he said. The
project will be among the topics during the sixth annual NASA Advanced
Concepts Institute meeting Tuesday and Wednesday at the Grand Hyatt
Hotel in Seattle. The meeting is free and open to the public.

Winglee acknowledges that it would take an initial
investment of billions of dollars to place stations around the solar
system. But once they are in place, their power sources should allow
them to generate plasma indefinitely. The system ultimately would
reduce spacecraft costs, since individual craft would no longer have to
carry their own propulsion systems. They would get up to speed quickly
with a strong push from a plasma station, then coast at high speed
until they reach their destination, where they would be slowed by
another plasma station.

"This would facilitate a permanent human presence in space," Winglee said. "That's what we are trying to get to."

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