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VASIMR = Variable Specific Impulse Magnetoplasma Rocket

a product of Ad Astra Rocket Company - a company owned by former astronaut & plasma physicist Franklin Chang Diaz. He started VASIMR at NASA, but as often happens the agency wouldn't spend enough money to keep it going so FCD took his baby and started Ad Astra.

Now he's working with NASA under a new agreement (one of several ongoing ones) just signed - see below before the pics.

think: 2001's Discovery plasma drive or USS Enterprise impulse drive, but for real. Plans are for one to be tested on the ISS.

If it works as expected it could be used to to re-boost its orbit as it decays, a job normally done by the shuttle or other spacecraft at the expense of a LOT of toxic hypergolic fuels. VASIMR would do the same job using a few tens of kg of hydrogen, argon or some other gas as reaction mass plus electricity.

This is a pure space drive - it can only work in a vacuum. Why so much interest? A rockets performance is measured by a its exhaust temperature & velocity and how long it fires. The temperature of a chemical rockets plume runs a few thousand degrees and its velocity a few thousand kph. They burn for a few minutes.

VASIMR temp: millions of degrees

Exhaust velocity: 10,000 ? 300,000 kph (the variable part)

Endurance: weeks to years

This plus it has demonstrated very high efficiencies. In its most evolved form VASIMR would be a real live fusion drive using deuterium "fuel." Yup, you read that right. In this form it would generate its own power.

They talk of a test unit of 200 kw, but the tech could well be scaled to tens or hundreds of megawatts. That would take you to Mars in a few weeks instead of 1-2 years.

PRESS RELEASE 080311, March 8, 2011

AD ASTRA AND NASA SIGN SUPPORT AGREEMENT ON VASIMR? TECHNOLOGY

[Houston, TX For immediate release] ? Ad Astra Rocket Company and NASA Johnson Space Center (JSC) have signed a Support Agreement to collaborate on research, analysis and development tasks on space-based cryogenic magnet operations and electric propulsion systems currently under development by Ad Astra. The agreement was signed on March 2, 2011 by NASA-JSC Director of Engineering, Mr. Stephen J. Altemus and Ad Astra?s Chief Executive Officer, Dr. Franklin R. Chang Diaz. The Support Agreement is the fourth entered into by the parties under an ?Umbrella? Space Act Agreement, executed in December of 2007. That document established the basic framework for collaboration and serves as host to support agreements, such as this one, that define specific tasks and objectives to be accomplished over a certain period.

Among its most significant elements, this Support Agreement provides for bilateral engineering consultation in NASA?s and Ad Astra?s respective areas of expertise, including Ad Astra?s VASIMR? technology and NASA?s expertise in spacecraft development. Ad Astra will provide NASA with an assessment of VASIMR??s high power low thrust trajectories over a number of mission scenarios ranging from near-Earth to deep space, while NASA will support Ad Astra?s efforts to mature the design of the 200 kW VF-200 VASIMR? flight demonstrator. This support includes, among other things, engineering design on two of the VF-200 flight demonstrator?s subsystems, integration support and structural engineering of interfaces with a launch vehicle and a potential flight platform (e.g. ISS or free flyer). The Support Agreement also provides for the use of specialized NASA facilities and equipment that may be required for some of the testing.

VX-200: 200 KW VASIMR drive (test chamber in background)

vasimrbus.jpg

VX-200 firing at full power

vasimr_vx200_ich.jpg

thanks as always Doc, but it bothers me that you keep saying it takes 1-2 years to go to Mars! Even the unpowered/low powered stuff we've sent so far has made it there in under 8 months on close approach...and Admin Bolden said this will take us to Mars in days if it works. well, i guess anything under a month is days by default...

Space elevator is pie in the sky with far more problems than fixes.

The real economical way to orbit is to use flyback boosters or motherships like the Skylon being developed in the UK;. Its SABRE engine is an air breather on takeoff and uses liquid oxygen at high altitudes. Once in orbit a smaller ship is deployed that takes the crew to an exploration-class ship in orbit or at EML-1 and returns to an ordinary runway. The economy comes from easy, rapid re-use and the cheap fuel. The less you throw away, the better.

1-2 years to Mars is based on the travel times for the 2 different trajectories using chemical fuels. Halve those if you use nuclear thermal, but it's ~39 days with a 200 MW VASIMR propelled crossing, almost half of that spiraling out around Earth building up speed. During this time an abort is possible if something breaks. Once VASIMR slingshots it out of Earth orbit the crossing is VERY fast.

The thing about isn't that VASIMR has tons of thrust, it doesn't. The advantage is that it uses very little propellant mass and it can run for months or years at a pop. Conbined these result in a high Specific Impulse, aka efficiency.

A high SI chemical rocket has an SI of 200-450.

Nuclear thermal has an SI of maybe 1000-1500.

VASIMR's SI can go as high as 30,000. Yikes!

Hence all the hubub.

Space elevator is pie in the sky with far more problems than fixes.

Yeah but its a shame really, simple prospect but not going to work. Used to see these in sci-fi years ago which is why I included it.

The real economical way to orbit is to use flyback boosters or motherships like the Skylon being developed in the UK;. Its SABRE engine is an air breather on takeoff and uses liquid oxygen at high altitudes. Once in orbit a smaller ship is deployed that takes the crew to an exploration-class ship in orbit or at EML-1 and returns to an ordinary runway. The economy comes from easy, rapid re-use and the cheap fuel. The less you throw away, the better.

Completely agree this will be the way to go without going in to too much science fiction

Sounds like you know a lot about this kind of stuff though?

i knew Doc would would shoot down your space elevator/skyhook assertion and start talking about SABRE again...he's too much of a realist. i think space elevators are very doable but of course the engineering has to be more mature than what we have right now. i mean, what about all that silicon and carbon nanotube stuff? that should be good enough even with Earth gravity. on Mars an elevator will be easy, just ask Kim Stanley, he's built one for $120 billion back in 1993...come on Doc, if we don't have a sense of humor about this we're done for!

and you know better than i do that the probes take like 8 months to get to Mars, stop it with the 1-2 years already! And thanks for explaining the VASIMR transit to Mars, didn't know so much of it is supposed to be close to Earth.

  • 3 months later...

Paper presented at the Space, Propulsion and Energy Sciences Forum, March 15-17 2011 at the University of Maryland

VASIMR Human Mission to Mars (PDF)....

This one is nothing we haven't read before, but a VASIMR article is on the Voice Of America site -

http://www.voanews.com/english/news/science-technology/Former-Astronaut-Develops-Powerful-Rocket-123960664.html

There's nothing primitive about VASIMR - it would be the fastest planetary drive ever and it has the basics to become a fusion drive.

A money driven schedule because of limited NASA funding for exploration. Doesn't presume commercial getting involved.

  • 10 months later...

Aviation Week....

Ad Astra Eyes SpaceX Commercial Model For Deep Space

The success of the SpaceX/Dragon resupply mission to the International Space Station has not been lost on Ad Astra Rocket Co., a seven-year-old venture focused on the development of advanced electric plasma propulsion systems for commercial in-space transportation.

?That is the proof in the pudding,? says Jared Squire, Ad Astra?s senior vice president for research, of the nine-day SpaceX pathfinder mission nurtured by NASA?s Commercial Orbital Transportation Services (COTS) program. ?That type of relationship works.?

Ad Astra envisions a similar NASA initiative to foster the next step beyond orbital cargo missions ? the private sector delivery of supplies to the Moon?s L-1 and L-2 Lagrange points, asteroids and to Mars orbit powered by the company?s Variable Specific Impulse Magnetoplasma Rocket (Vasimr) in support of future human deep-space exploration.

Squire is not prepared to suggest a figure, but COTS will channel $396 million to SpaceX as a development partner. Hawthorne, Calif.-based SpaceX, founded by billionaire Elon Musk, expects to begin regular cargo delivery missions to the station later this year under a $1.6 billion, 12-flight NASA contract signed in late 2008.

?We are thinking of something similar,? Squire says. ?If you have the surface-to-orbit capability in a reliable way, now you need an orbital transfer vehicle ? a vehicle that can take large payloads and deliver them wherever in space efficiently. Electric propulsion in general has a capability to do that, and in the near term solar-electric has a lot of potential.?

In addition to deep-space deliveries, Ad Astra is looking at a Vasimr-powered spacecraft for the removal of menacing orbital debris.

The technology is the brainchild of Franklin Chang-Diaz, Ad Astra CEO, who nurtured the project while a grad student in physics at Massachusetts Institute of Technology and then as an astronaut at NASA?s Johnson Space Center.

In late May, Ad Astra and NASA expanded a five-year-old Space Act Agreement (SAA) focused on further Vasimr development to begin the safety, reliability and mission assurance phase of the project. The amendment commits the equivalent of one full-time NASA expert to the safety process in exchange for an agency knowledge gain in the technology.

The long-running SAA, which does not involve an exchange of funds, is leading toward the launch of a 200-kw Vasimr prototype to the space station or an independent orbiting free-flyer in the 2015 timeframe for a three-year checkout of performance and reliability, Squire says.

The notional launch target has slipped a year and remains vulnerable to NASA budgeting and the future of the station?s status as a national laboratory. While Ad Astra has not committed to a launch provider, Orbital Sciences Corp. appears to provide the best match. Orbital Sciences represents NASA?s second COTS partner, and is developing the Cygnus/Antares system for that mission. A test-flight success similar to SpaceX?s will make Orbital Sciences eligible for $1.9 billion under an eight-flight ISS supply mission agreement with NASA, also awarded in 2008.

Like SpaceX, Ad Astra envisions a future role in human space transportation. Theoretically, a nuclear-powered version of Vasimr could speed a human crew to Mars in 39 days, versus 7-10 months with conventional propulsion.

The VF-200-1 prototype envisioned for the space station would operate under battery power ? perhaps something similar to the battery specified for the sporty electric Tesla roadster, another Elon Musk initiative. Even with vast solar power, the station?s electrical grid could not meet Vasimr?s sustained power demands, Squire says.

From there, Ad Astra would look to advanced space solar power for electricity. Vasimr outperforms its chemical rivals by heating a gas fuel to super-high temperatures with focused radio waves. The resulting plasma is contained and directed with a protective magnetic field generated by superconducting magnets.

In ground vacuum-chamber testing, Ad Astra has relied on argon as a fuel source. But a switch to heavier krypton, which offers higher thrust at lower specific impulse under power limitations, is being evaluated.

  • 2 years later...

Connected to NASA's Next STEP where VASIMR is getting $10m in R&D over 3 years, with access to NASA labs.

https://www.neowin.net/forum/topic/1251796-nasa-nextstep-advanced-project-awards/?view=getnewpost

http://adastrarocket.com/AdAstraRelease033115final.pdf

PRESS RELEASE 033115, March 31, 2015

AD ASTRA ROCKET COMPANY WINS MAJOR NASA ADVANCED PROPULSION CONTRACT

[Webster, Texas

They didn't get to the required TRL, and large Hall thrusters have exceeded its performance.

IMO MSNW's plasmoid ELF-250 thruster, and their inertial confinement fusion rocket, have a better shot.

Their ELF thrusters are pulsed, but can do 1,000 pules/second using about any fuel you can squirt - atoms or molecules. Even water, hydrazine, co2 or raw mixed atmospheric gases. Cool stuff.

Still not what they need for lifting off large bodies using just those propulsion systems (they could do it from comets and small icy bodies). Seems like icy bodies would work best, as those are mostly Hydrogen, Oxygen, Cyanide and other rare gases. Perform some chemistry to break down the ices, compress the gases into separate tanks (or just what gases you need, expel the ones they don't), and you've refueled your craft and even provided yourself with breathing Oxygen. Make sure you get rid of the Cyanide ... ;)

 

As Doc said, not quite Mr. Fusion, but far more flexible than before. You've got more choices.

  • 1 month later...

VASIMR progress talk at ISDC 2015 by Dr. Franklin Chang Diaz

Highlights

>10,000 firings of VX-200.

CDR in 2016, ISS flight milestone in early 2018.

No plume neutalization needed as it consists of both electrons and ions - self neutralizing.

Thrust with argon is 6N with an Isp of 5,000s and 70% efficiency. Krypton should deliver an efficiency of 75%.

ISS reboost currently requires 7 tonnes of propellant and costs $210 million/year. An 80 kW VASIMR would cost 10% of that.

http://www.youtube.com/watch?v=5Aoa0waHiHk

Wow.....great thread.....I remember years ago reading of Dr Diaz's work...very exciting but then I lost track of what happened. Any idea if NASA still plans on installing a boost system on the ISS? Curious to see if they use Vasimr or ELF variants for boost or manoeuvring either on the ISS or future craft. The X-37B experiments will really help as well, being in situ..Cheers... :D

A 200 kW temporary VASIMR testbed goes to ISS about early 2018. If it works out an 80-100 kW VASIMR reboost module could go up later.

ELF is extremely interesting too; lightweight, high thrust & efficiency it doesn't need pure nobel gases as propellant. It can run on them, but also Earth air, Martian atmosphere, water, CO2 and other molecular materials. Because it could conceivably power a hypersonic vehicle at high altitudes as an air breather the USAF has high interest. So does NASA for use as an upper stage powered by beamed power.

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