Two Weeks To Mars With Nexis Ion Engine

Funny thing is that Werner Von Brown was the one who proposed this ion
engine more than 50 years ago. What was it with these Germans --
Einstein and Von Brown. Too bad they didn't team up. Maybe together
they could have put together a craft that approached the speed of
light.

Date: 12-27-2003
Ion Engine Design Passes Key NASA Test

A team of engineers at NASA's Jet Propulsion Laboratory, Pasadena,
Calif, successfully tested a new ion propulsion engine design, one of
several candidate propulsion technologies under study by NASA's
Project Prometheus.
The event marked the first performance test of the Nuclear Electric
Xenon Ion System (NEXIS) engine at the high-efficiency, high-power,
and high-thrust operating conditions needed for use in large-scale
nuclear electric propulsion applications.

The NEXIS engine was powered using commercial electrical power. Ion
engines used on NASA's proposed Jupiter Icy Moons Orbiter (JIMO) will
draw power from an onboard nuclear reactor. The ion engines, or
electric thrusters, would propel the orbiter around three of the icy
moons orbiting Jupiter, Ganymede, Callisto and Europa, to conduct
extensive, close-range examinations and to determine their potential
for sustaining life.

"On the very first day of performance testing, the NEXIS thruster
demonstrated one of the highest efficiencies of any xenon ion thruster
ever tested," said Dr. James Polk, the principal investigator for the
test at JPL. "We expect the NEXIS design to demonstrate both the
performance and projected lifetime necessary for the proposed Jupiter
mission," he said.

The test was conducted December 12. It used the same vacuum chamber,
where the Deep Space 1 ion thruster set the all time endurance record
of 30,352 hours (nearly 3.5 years) of continuous operation. The NEXIS
engine operated at more than 20 kilowatts, nearly 10 times that of the
Deep Space 1 thruster. It is designed to process two metric tons of
propellant, 10 times the capability of Deep Space 1, and operate for
10 years, two to three times the Deep Space 1 thruster life.

Team members working on the NEXIS engine also helped develop the first
ion engine ever flown on NASA's highly successful Deep Space 1
mission. It validated 12 high-risk advanced technologies, among them
the use of the first ion engine in space.

"The NEXIS thruster is a larger, high performance descendant of the
Deep Space 1 thruster that achieves its extraordinary life by
replacing the metal, previously used in key components, with advanced,
carbon based materials," said Tom Randolph, NEXIS program manager at
JPL.

Unlike the short, high-thrust burns of most chemical rocket engines,
the ion engine emits only a faint blue glow of electrically charged
atoms of xenon, the same gas found in photo flash tubes and in many
lighthouse bulbs. The thrust from the engine is as gentle as the force
exerted by a sheet of paper held in the palm of your hand. However,
over the long haul, the engine can deliver 20 times as much thrust per
kilogram of fuel than traditional rockets.

"This test, in combination with the recent successful test of the High
Power Electric Propulsion ion engine at NASA's Glenn Research Center,
Cleveland, is another example of the progress we are making in
developing the technologies needed to support flagship space
exploration missions throughout the solar system and beyond," said
Alan Newhouse, Director, Project Prometheus. "We have challenged our
team with difficult performance goals and they are demonstrating their
ability to be creative in overcoming technical challenges."

NASA's Project Prometheus is making strategic investments in space
nuclear fission power and electric propulsion technologies. The
technology may enable a new class of missions to the outer Solar
System, with capabilities far beyond those possible with current power
and propulsion systems. The JIMO mission could launch during the next
decade and provide NASA significantly improved scientific and
telecommunications capabilities and mission design options. Instead of
generating only hundreds of watts of electricity like the Cassini or
Galileo missions, which used radioisotope thermoelectric generators,
JIMO could have up to tens of thousands of watts of power, increasing
the potential science return many times over.

A team of engineers from JPL; Aerojet, Redmond, Wash.; Boeing Electron
Dynamic Devices, Torrance, Calif.; NASA's Marshall Space Flight
Center, Huntsville, Ala.; Colorado State University, Fort Collins,
Colo.; Georgia Institute of Technology, Atlanta; and the Aerospace
Corporation, Los Angeles is developing the NEXIS.

The thrust from the engine is as gentle as the force
exerted by a sheet of paper held in the palm of your hand.

So what is that, an ounce of thrust?

The thrust from the engine is as gentle as the force
exerted by a sheet of paper held in the palm of your hand.

So what is that, an ounce of thrust?

wrote in message
om...
Funny thing is that Werner Von Brown was the one who proposed this ion
engine more than 50 years ago. What was it with these Germans --
Einstein and Von Brown. Too bad they didn't team up. Maybe together
they could have put together a craft that approached the speed of
light.

Date: 12-27-2003
Ion Engine Design Passes Key NASA Test


This engine is designed for long-duration missions (such as Voyager) and not
suitable for human-space travel. A Mars mission wil not be cut down to 2
weeks with this engine as it takes a long time to accelerate to any
meaningfull speed (far longer than 2 weeks).

Does anyone have efficiency figures for electrical engines, measured as:

Kinetic Energy of exhaust / Electrical energy input




wrote in message . com...
Funny thing is that Werner Von Brown was the one who proposed this ion
engine more than 50 years ago. What was it with these Germans --
Einstein and Von Brown. Too bad they didn't team up. Maybe together
they could have put together a craft that approached the speed of
light.

Date: 12-27-2003
Ion Engine Design Passes Key NASA Test

A team of engineers at NASA's Jet Propulsion Laboratory, Pasadena,
Calif, successfully tested a new ion propulsion engine design, one of
several candidate propulsion technologies under study by NASA's
Project Prometheus.
The event marked the first performance test of the Nuclear Electric
Xenon Ion System (NEXIS) engine at the high-efficiency, high-power,
and high-thrust operating conditions needed for use in large-scale
nuclear electric propulsion applications.

The NEXIS engine was powered using commercial electrical power. Ion
engines used on NASA's proposed Jupiter Icy Moons Orbiter (JIMO) will
draw power from an onboard nuclear reactor. The ion engines, or
electric thrusters, would propel the orbiter around three of the icy
moons orbiting Jupiter, Ganymede, Callisto and Europa, to conduct
extensive, close-range examinations and to determine their potential
for sustaining life.

"On the very first day of performance testing, the NEXIS thruster
demonstrated one of the highest efficiencies of any xenon ion thruster
ever tested," said Dr. James Polk, the principal investigator for the
test at JPL. "We expect the NEXIS design to demonstrate both the
performance and projected lifetime necessary for the proposed Jupiter
mission," he said.

The test was conducted December 12. It used the same vacuum chamber,
where the Deep Space 1 ion thruster set the all time endurance record
of 30,352 hours (nearly 3.5 years) of continuous operation. The NEXIS
engine operated at more than 20 kilowatts, nearly 10 times that of the
Deep Space 1 thruster. It is designed to process two metric tons of
propellant, 10 times the capability of Deep Space 1, and operate for
10 years, two to three times the Deep Space 1 thruster life.

Team members working on the NEXIS engine also helped develop the first
ion engine ever flown on NASA's highly successful Deep Space 1
mission. It validated 12 high-risk advanced technologies, among them
the use of the first ion engine in space.

"The NEXIS thruster is a larger, high performance descendant of the
Deep Space 1 thruster that achieves its extraordinary life by
replacing the metal, previously used in key components, with advanced,
carbon based materials," said Tom Randolph, NEXIS program manager at
JPL.

Unlike the short, high-thrust burns of most chemical rocket engines,
the ion engine emits only a faint blue glow of electrically charged
atoms of xenon, the same gas found in photo flash tubes and in many
lighthouse bulbs. The thrust from the engine is as gentle as the force
exerted by a sheet of paper held in the palm of your hand. However,
over the long haul, the engine can deliver 20 times as much thrust per
kilogram of fuel than traditional rockets.

"This test, in combination with the recent successful test of the High
Power Electric Propulsion ion engine at NASA's Glenn Research Center,
Cleveland, is another example of the progress we are making in
developing the technologies needed to support flagship space
exploration missions throughout the solar system and beyond," said
Alan Newhouse, Director, Project Prometheus. "We have challenged our
team with difficult performance goals and they are demonstrating their
ability to be creative in overcoming technical challenges."

NASA's Project Prometheus is making strategic investments in space
nuclear fission power and electric propulsion technologies. The
technology may enable a new class of missions to the outer Solar
System, with capabilities far beyond those possible with current power
and propulsion systems. The JIMO mission could launch during the next
decade and provide NASA significantly improved scientific and
telecommunications capabilities and mission design options. Instead of
generating only hundreds of watts of electricity like the Cassini or
Galileo missions, which used radioisotope thermoelectric generators,
JIMO could have up to tens of thousands of watts of power, increasing
the potential science return many times over.

A team of engineers from JPL; Aerojet, Redmond, Wash.; Boeing Electron
Dynamic Devices, Torrance, Calif.; NASA's Marshall Space Flight
Center, Huntsville, Ala.; Colorado State University, Fort Collins,
Colo.; Georgia Institute of Technology, Atlanta; and the Aerospace
Corporation, Los Angeles is developing the NEXIS.

Alex Terrell wrote:
Does anyone have efficiency figures for electrical engines, measured as:

Kinetic Energy of exhaust / Electrical energy input


PPS-1350 (aka the engine on SMART-1) provides about 0.68 of thrust
for 1.2kW input.

Take a look at say:
http://spis.onecert.fr/spine/meeting...des/Prioul.pdf

--
Sander

+++ Out of cheese error +++

(Alex Terrell) writes:

Does anyone have efficiency figures for electrical engines, measured as:

Kinetic Energy of exhaust / Electrical energy input

For Ion thrusters, as in the article, it's 50-70%.

Hall Effect thrusters run 40-60%

Arcjets, 30-40%

Resistojets, 60-80%

Pulsed Plasma Thrusters, 5-10%


Everything else is vaporware or laboratory hardware, and hard to pin
real numbers on. And note that efficiency is only one parameter of
interest, so you can't just say that resistojets are automatically
the best at 80% efficient (the Isp sucks rocks), or that PPTs are
worthless at a pathetic 5-10% (they have no moving parts and can
be made almost arbitrarily small and cheap).


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writes:

Funny thing is that Werner Von Brown was the one who proposed this ion
engine more than 50 years ago. What was it with these Germans --

Conceptually, nearly all rocket engines are _EXTREMELY_ simple devices,
involving no physics discovered after WW2. The devil has been in the
_PRACTICAL ENGINEERING DETAILS_, not the concepts.


Einstein and Von Brown. Too bad they didn't team up.

It is unlikely that they would have accomplished much more together
than they accomplished separately. Einstein was a theoretical physicist,
not an engineer, and as I noted earlier, the problem was not with the
theory, but with the practical engineering.


Maybe together they could have put together a craft that approached
the speed of light.

Highly unlikely. They would have been stopped by the same reason we a
Lack of a sufficient power source. Even matter/antimatter power maxes out
around 80% of lightspeed, unless you use truly ridiculous amounts of it !!!


-- Gordon D. Pusch

perl -e '$_ = \n"; s/NO\.//; s/SPAM\.//; print;'

Gordon D. Pusch wrote:

than they accomplished separately. Einstein was a theoretical physicist, not an engineer, and as I noted earlier, the problem was not with the

But note that Einstein was not above taking part in developing a (the
first?) household refrigerator. It never made it to market, because of
the increasingly bad economic situation at that time, but nevertheless
...