Scientists have recently announced a
breakthrough with an ion thruster that could one day take humans to the Mars. It’s
called the X3 thruster, a type of the ion propulsion known as a Hall thruster. This
technology is alluring because it can theoretically achieve higher speeds than
conventional chemical propulsion.
In a series of tests at
NASA’s Glenn Research Center, researchers said they had now achieved a record
power output for a Hall thruster, opening up new avenues of research.
"We have shown that X3
can operate at over 100 kW of power," Alec Gallimore, the project’s lead
and the dean of engineering at the University of Michigan, told Space.com.
"It generated 5.4 Newtons of thrust, which is the highest level of thrust
achieved by any plasma thruster to date." (The previous record was 3.3 Newtons.)
Ion thrusters are alluring
because they promise high thrust with little fuel input. With little propellant
needed, they can theoretically operate for much longer than conventional
thrusters, achieving much higher speeds. We’ve tested out quite a
few, too. The longest-running is on NASA’s Dawn spacecraft, which is currently
in orbit around the dwarf planet Ceres and launched in 2007.
However, that has a thrust
of just 90 microNewtons (0.00009 Newtons). Hall thrusters offer a much higher
thrust. They involve accelerating plasma at extremely high speeds. Electrons
are used to bump into atoms, normally of xenon gas. This knocks off more
electrons, producing positive ions and thrust. Slowly, over time, this
continually increases the speed of a spacecraft.
In theory, a Hall thruster
could get a spacecraft up to 40 kilometers (25 miles) per second, eight times
faster than a chemical propulsion spacecraft with a top speed of 5 kilometers
(3 miles) per second.
Thus, they are hugely
promising for spaceflight. If used on manned missions to Mars, for example, the
spacecraft could require less propellant and thus more easily be launched into
orbit. However, Gallimore noted such an engine would need a lot of power, which
is why the X3 thruster is so promising.
By using a bigger thruster,
the team said they use multiple channels of plasma rather than just a single
channel – called a nested channel. This could allow for these high speeds to be
achieved.
This is not the only ion
thruster research being conducted. NASA has several other projects on the go,
to try and improve methods of spaceflight. Maybe the first humans that go to
Mars will have a revolutionary ion thruster to thank.
No comments