New Nuclear-powered Spaceship Design Revealed

Iddo Genuth writes "A U.S. based company introduced an innovative propulsion system that could significantly shorten round trips from Earth to Mars (from two years to only six months) and enable future spaceships to reach Jupiter after one year of space traveling. The system, which may dramatically affect interplanetary space travel is called the Miniature Magnetic Orion (Mini-Mag Orion for short), and is an optimization of the 1958 Orion interplanetary propulsion concept."

Comments

Didn't we

[scoot80]

recently have an article about trip to mars in a week? So.. this is really.. an inferior mode of transport for all those Mars holidayers...

The best part of the mini-mag design

[Anonymous Coward]

If you unscrew the cap in the stern of the spacecraft, you will find a spare nuclear reactor behind the battery terminal.

Reduces travel time how?

[Cousarr]

First off, I am not a rocket scientist, but I am studying for a BS in Aerospace Engineering.

How exactly is this supposed to reduce travel time? Current lengths of travel are not due to a lack of available thrust or due to amount of fuel available but rather the path taken to reach the destination. Currently in order to travel to say Mars Hohman transfers are often used. These paths and others like them take a certain amount of time to complete, and stronger engines or more available Delta-V allow only for more instantaneous entrances of the transfers or more allowed change in course once at the ship's destination.

In order to reduce time traveled a different orbital mechanic is needed. Even if a ship were to travel in a straight line toward a destination at a rapid enough speed that it would not have to meet up with it too much further along in its orbit it would have to be able to kill relative speed quickly enough to enter a capture orbit.

Anyone know what orbital transfer method they're saying that this engine makes possible?

Re:Reduces travel time how?

[StefanJ]

As I recall, Hohman orbits are nice ellipses with body A at perisol and body B and aposol. You make a burn to get into it and out of it; the delta-v required is the difference in velocity between a body in a "circular" orbit at that radius and the velocity of a body in the elliptical orbit. If the planet happens to be at that point, you then just need to make another burn to get into orbit. Timing is important.

Even Hohman orbits are too "spendy" for chemically fueled rockets. Thus the complex back-and-forth gravity-assist paths that NASA probes take on the way to the outer planets, and the use of aerobreaking by Mars probes.

Other, faster transfers are possible. You just enter another sort of elliptical orbit whose path intersects earth's orbit when you leave it, and the destination planet's orbit at a time when the planet will be there. Of course, you have to have a spaceship capable of the much greater change in velocity to enter these orbits.

The linked-too documents suggest that the "mini mag" is not only fuel efficient (read: high Isp), but has a decent amount of thrust. This means it CAN make the drastic changes in velocity necessary.

Transfer orbit

[Kadin2048]

I believe they are using the "Journalist Transfer Orbit." This is a highly specialized piece of orbital mechanics: basically, you take the average distance to the destination as given by Wikipedia and divide by the spacecraft's top speed.

Re:jupiter?

[moosesocks]

Obligatory:

Fry: Hey, as long as you don't make me smell Uranus. (laughs)
Leela: I don't get it.
Professor: I'm sorry, Fry, but astronomers renamed Uranus in 2620 to end that stupid joke once and for all.
Fry: Oh. What's it called now?
Professor: Urectum.

Blog troll. Link to real info here.

[Animats]

First, this is a blog troll, to drive traffic to some ".info" site. The actual paper, "Proposed Follow-on Mini-Mag Orion Pulsed Propulsion Concept" presented at an AIAA conference last year, is more useful.

The basic idea is to create a small fission (not fusion) explosion using magnetic compression. Nuclear weapons use chemical explosives to create an implosion, and during the implosion the fissionable material is compressed hard enough to get a 1.5x to (maybe) 2x density increase. With magnetic compression, a small pellet can be compressed hard enough to get a 10x density increase. This allows smaller explosions, around 50 gigajoules instead of the 20 terajoules of a fission bomb. They want to use curium or californium as the fuel, rather than plutonium.

They also want to use magnetic containment, rather than an Orion-style "pusher plate" sprayed with oil. Unclear if that can be made to work.

The experimental work (they compressed an aluminum cylinder with a big magnet at Sandia) was done back in 2002. This isn't really under active development.

It's not a totally unreasonable idea, but it would be a huge job to make it work. For one thing, the plan is to assemble a large spacecraft in orbit, not to take off from Earth. It doesn't help with the problem of putting mass in orbit.

Re:That's nothing..

[Rei]

Still, this has very little to do with Orion apart from them both being nuclear pulse propulsion. They only call it a successor to Orion because most people are familiar with Orion.

Orion has already been obsoleted by a similar (but much more effective) design using normal-sized nuclear explosions -- Medusa. Medusa reverses the Orion design, having a parachute in front towing the craft, and detonating the explosives in front of the parachute. It uses structures in tension instead of compression (lighter), it allows the explosions to be further from the craft (less radiation), allows a longer acceleration stroke (smoother acceleration), and captures a larger percentage of the explosive energy.

Re:What about manned?

[modecx]

Isn't it kinda sad that people on a site which is supposedly for nerds can't naturally grasp the idea of waves, pulse-width, modulation, duty cycle, and psychophysical thresholds?

Exactly what kind of nerds are they cranking out these days?

Re:What about manned?

[PitaBred]

It's now more popular to be a nerd, rather than just a state of being for people who are truly drawn to it, so you start getting a lot of wannabe's who can't hack it intellectually, but are still drawn to the "lifestyle", or more the perks of being known as a nerd. For example, look at Apple users ;)