Mar 3 2010 3:06pm
Around the Solar System in 39 Days (Well, at least to Mars)

Earth to Mars in a little over a month. Yes, you heard that right. Not the one-and-a-half-years there, one-and-a-half-years back, but around the Earth-Mars block in less than 80 days. (Credit: NASA/AdAstra)

How? By using a propulsion system orders-of-magnitude greater than current systems.

Meet VASIMR, the Variable Specific Impulse Magnetoplasma Rocket.

Mars isn’t really the only place that we can go. With a megawatt-class VASIMR, basically we will have access to the entire solar system. Mars is an interesting place, but so are Europa and Ganymede and Enceladus and Titan. These are places where we might find extraterrestrial life.
Dr. Franklin Chang-Diaz [more]

Conventional Rockets vs. VASIMRs

Conventional rockets rely on the combustion of rocket fuel for propulsion; put otherwise, they rely on chemical reactions. (Credit: A&S Smithsonian/Ad Astra)

VASIMRs—antecedent to The Enterprise’s nacelles—rely on plasma for propulsion. Plasma—considered a distinct state of matter alongside solids, liquids, and gases—is a gas that has become ionized, often by extreme heat. Stars are made of plasma, as are lightening, polar aurorae, and most flames. (Credit: NASA)

How can something as hot as plasma be handled? With electromagnetic fields.

Superconductors create electromagnetic fields that contain the plasma, shape it into a jet, and point it in the right direction—out the back of the rocket. Nuclear reactions generate the electricity required.

How close is VASIMR to deployment?

A July 6, 2009 press release from the company developing VASIMR in collaboration with NASA reads:

Ad Astra Rocket Company has successfully demonstrated operation of its VX-200 plasma engine first stage at full power and under superconducting conditions in tests conducted today at the company’s Houston laboratory.

This achievement is a key milestone in the engine’s development and the first time a superconducting plasma rocket has been operated at that power level.

Videos of the AD Astra VASIMR full-power, full-field firing are at

On September 30, 2009:

Ad Astra Rocket Company’s VASIMR VX-200 rocket prototype reached its highly- coveted 200kW maximum power milestone at 11:59 am (CST) in tests conducted at the company’s Houston laboratory.

The DC power trace actually exceeded the design requirement by 1 kW and exhibited the clear signature of a well established plateau at peak power.

As announced on January 24, 2010:

After five years of operations, the company is maintaining a fast pace, focusing on maturing the VASIMR technology to flight readiness.

Even more exciting—if you are a VASIMR fan—the current administration has diverted billions of dollars from the earlier plans to return to the moon to better rocketry.

Chang-Diaz is planning for an orbital deployment by the end of 2013, and is already working with private space firms SpaceX and Orbital Science Corporation to make this a reality.


Great presentation by Dr. Franklin Chang-Diaz on YouTube (5 stars).

Wow—the firing of the VASIMR engine.

Air & Space Museum + Ad Astra: very cool silent Lunar Run video

VASIMR Online/Print

Down-to-earth interview with Dr. Franklin Chang-Diaz in SEED magazine.

NASA technical briefing: VASIMR.

Lots of information, images, etc. at the Ad Astra Rocket Company site.

Dr. Kirtland C. Peterson—“Cat” to his friends and colleagues—feeds his left brain with science, his right brain with the rich feast of fiction, including SF and fantasy. Among his life’s highlights are sitting in the pilot’s seat of a shuttle prepping for launch at the Kennedy Space Center, and accepting Brannon Braga’s invitation to pitch Star Trek scripts at Paramount in LA. Recently finished The Hobbit (read most marvelously by Rob Inglis), Ursula K. Le Guin’s A Wave in the Mind: Talks & Essays on The Writer, The Reader & The Imagination, and Alice Munro’s The View from Castle Rock. Just started J.R.R. Tolkein’s The Monsters and the Critics and Other Essays.

Luke M
1. lmelior
Nuclear reactions generate the electricity required.
That's the real trick, isn't it? President Obama's seeming friendliness towards nuclear power is very promising, but nuclear power in space remains a political problem, if not a technological one. Maybe since the Russians are full speed ahead on their own nuclear powered spacecraft, it'll push those crotchety guys in DC towards allowing it.

I wish I could claim insider information, but alas, I am too low on the totem pole. I do hope we get it though. By the way, I know it's wrong all the way up to the AFP article, but it's Orbital Sciences.
Dr. Kirtland C Peterson
2. catsongs
lmelior—good points!

I too hope the "crotchety guys in DC" keep us in the game!


Someone from the Tor Universe sent me a marvelous video of a different, cutting-edge rocket propulsion technology.

Whoever you are: THANKS!

Mike Conley
3. NomadUK
It's not a matter of some crotchety guys in DC allowing it, it's a matter of negotiating within the framework of the Outer Space Treaty, or the Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies, 1967. This treaty explicitly prohibits the installation of nuclear weapons in space or Earth orbit, and one could argue that a nuclear-powered spacecraft might fit within that definition.

The best approach would be to make the effort an international one, so that nobody feels the need to object.
4. NickD
Hello Dr. Peterson,
sorry, but I cannot find your email to contact you.
About the VASIMR screenshots you asked for: - these are taken by me from Orbiter using my first VASIMR craft model. Actually this craft is not close to real project, because in time I've made it I had no enough data about it.
Screenshots here: (only screenshot section)
was taken by me and by CurlSnout from Orbiter, using my USS Bekuo model. You can use them freely.
If you have more questions or need more help, you can write at my email ( Please provide your email, where I can answer.
Best regards,
Nikolay Dimitrov
Dr. Kirtland C Peterson
5. catsongs

Thanks for your thoughts!

For anyone interested, from Wikipedia...

The Outer Space Treaty represents the basic legal framework of international space law. Among its principles, it bars States Parties to the Treaty from placing nuclear weapons or any other weapons of mass destruction in orbit of Earth, installing them on the Moon or any other celestial body, or to otherwise station them in outer space. It exclusively limits the use of the Moon and other celestial bodies to peaceful purposes and expressly prohibits their use for testing weapons of any kind, conducting military maneuvers, or establishing military bases, installations, and fortifications (Art.IV). However, the Treaty does not prohibit the placement of conventional weapons in orbit. The treaty also states that the exploration of outer space shall be done to benefit all countries and shall be free for exploration and use by all States.


As I understand it, discussions re. VASIMR and the use of nuclear power have turned on whether the nuclear reactor is a "weapon."

Concern, of course, is that regardless of whether or not it is a "weapon," getting nuclear material into orbit and having it in orbit around the Earth is... DANGEROUS!

Thanks again!

Luke M
6. lmelior
This treaty explicitly prohibits the installation of nuclear weapons in space or Earth orbit, and one could argue that a nuclear-powered spacecraft might fit within that definition.
A politician could (and would) argue that it does, but nobody that builds the rocket would. I'm quite sure that the hardware that makes up a fission reactor is quite different that the hardware that makes up a fission bomb. Not to mention weapons-grade fissionable materials are quite a jump above materials that can be used in a reactor. This is why the IAEA allowed countries like Iran to have centrifuges to enrich uranium. You only need 3-5% U-235 to run a reactor, but you need at least 20% for a dirty bomb. Note that Iran's latest batch of centrifuges are claimed (by Iran) to enrich to that level, which is why nobody is happy about it.

For reference, Little Boy was 80% U-235.

Like most things in science, though, there is probably a vanishingly small chance that detonation is possible. The more significant problem is radioactive material dispersing in the event of a launch failure. Russia made fission reactor-powered spacecraft, one of which crashed into Canada. It would be a pretty serious problem if it happened over a populated area, but we have the technology to ensure to a very high degree of confidence that doesn't happen.

Of course, vanishingly small is not zero, and politicians latch onto such things with tenacity.
Mike Conley
7. NomadUK
Imelior@6: Yes, well, just in case you hadn't noticed, people who build rockets don't run this planet.
Luke M
8. lmelior
Heh, indeed.

In any case, I'll be following the development of VASIMR with interest. It's a shame we still have to rely on chemical rockets to get to LEO, but it's definitely a step in the right direction.

Also, I've been meaning to say that Ad Astra (Latin for "to the stars" I believe), is an awesome name for an aerospace company.
Liza .
9. aedifica
lmelior: That is indeed what it means, and I've been thinking too that it's a great name for it!
Ashe Armstrong
10. AsheSaoirse
That whole article was sexy as hell. It made my brain shudder in delight. I sincerely hope that this comes to fruition as the positive consequences could rock our world.
Dr. Kirtland C Peterson
11. catsongs

"That whole article was sexy as hell. It made my brain shudder in delight."


Re. VASIMR, I agree! It'll be interesting to see if NASA runs with VASIMR, or whether it's a private company (US or otherwise) that does.

Chang-Diaz is 60. My bet: he's gonna want to see his engine in full operation before he turns 75!


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