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Tests are underway on a rocket technology that could
vastly shorten the time it takes for humans to get to Mars, greatly reducing
the risk of mechanical failures and other deadly space hazards on future
Mars-bound astronauts.
Costa Rica and U.S.-based Ad Astra Rocket Company
announced over the summer that it had completed a record 88-hour high-power
endurance test of its Vasimr VX-200SS plasma rocket at 80 kW. The test,
conducted at the company's Texas laboratory near Houston, constituted a new
high-power world endurance record in electric propulsion.
'Years of trial-and-error testing' for Vasimr rocket
"The test is a major success, the culmination
of years of trial-and-error testing and painstaking attention to detail and a
handsome reward for the team's tenacity and dedication," said Franklin R.
Chang DÃaz, Ad Astra's chairman and CEO, who flew on seven separate missions as
a NASA astronaut, logging 1,601 hours in space.
The Variable Specific Impulse Magnetoplasma Rocket
(Vasimr) rocket was designed to fly with an engine that uses nuclear reactors
to heat plasma to two million degrees. Hot gas is then channeled, via magnetic
fields, out of the back of the engine to propel it, in theory, at speeds of up
to 123,000 mph (197,950 km/h).
The goal for Ad Astra is to make much faster, but
also much safer spaceflight possible — despite the fact that Vasimr rockets
would send nuclear reactors hurtling through space at incredible speeds. Though
Vasimr launch vehicles will still require chemical rockets to reach orbit, once
there, the plasma engine (described in the video below) will be engaged,
greatly improving the safety of the crew, according to the company.
Four times faster than existing chemical rockets
In the seven months NASA estimates it would take to
fly humans to Mars, any number of catastrophic failures could occur. That's why
DÃaz said in a 2010 interview with Popular Science that "chemical rockets
are not going to get us to Mars. It’s just too long a trip."
A conventional rocket must use its entire fuel
supply in a single controlled explosion during launch before propelling itself
towards Mars. There is no abort procedure, the ship will not be able to change
course, and if any failure occurred, mission control would have a 10-minute
communications delay, meaning they could find themselves helplessly watching on
as the crew slowly dies.
Ad Astra's plasma rocket Vasimr, on the other hand,
will sustain propulsion throughout the journey to the red planet. It will
accelerate gradually until it reaches a maximum speed of 34 miles (54 km) per
second by the twenty-third day, making it four times faster than any existing
chemical rocket. This would reduce that estimated seven-month journey by
approximately six months.
Less time traveling through space means less
exposure to solar radiation — a recent study states that Mars missions should
not exceed four years for crew safety — less risk of mechanical failures, and
less of a health risk due to the muscle atrophy effects of zero-gravity. As the
ship's plasma engine can provide propulsion at any time, it could also change
course if required.
Following Ad Astra's successful plasma rocket
endurance test in July, the company announced its plans for the future.
"With a new set of engine modifications already in the manufacturing
stage, we'll now move to demonstrate thermal steady state at 100 kW in the
second half of 2021," DÃaz said in Ad Astra's press release.
Other firms such as DARPA are also developing
nuclear-powered rockets — the Pentagon agency announced this year that it wants
to demonstrate a nuclear thermal propulsion system above low Earth orbit in
2025. Spaceflight looks like it's on course to go nuclear, in a move that would
greatly enhance humanity's capacity to launch to unexplored regions of our
universe.