Thruster May Shorten Mars Trip from 6 Months to 1 Week

See that small mirror on the left? That's the only part that is driven by the photon thrust.

So as a method of keeping station in a cluster of satellites, I can see it being useful.

As a new sort of general-purpose booster, it's a bit more bizarre and complex. You essentially have to have an anchor - that's the bit with the conventional thruster on the right side. It's being pushed back (you don't want that) while the small bit on the left is being pushed forward (that's your spaceship). In order to keep the "anchor" from moving away by reaction, they are burning the rocket fuel there instead of in the "craft".

The thing's a bit different if it's a cluster stabilizer.

From the looks of it, I don't think you would have to worry too much about the G forces when accelerating, it seems like it would gradually accelerate a spacecraft.

Also, here is part of an article I quoted earlier,

Photonic Laser Thruster Demonstrated, Could Accelerate Spacecraft to Near-Light Speeds

The technology prototype generates the power of an industrial or military laser from from an egg sized head. The technology is economical and has been confirmed by repeated experiments. The institute is seeking funding to scale up the project.

How much energy does it take to power an industrial or military laser?

I've got another question.

How would you get back?

It doesn't look like you could tow a launch platform/anchor with the spacecraft to put in place to "push" you back. Launch platforms/anchors will have to be set up in various places with enough fuel for the rockets to keep them stable in space and with enough energy for the military/industrial lasers to make the going and comings of manned spacecraft feasible.


[edit on 11/9/07 by Keyhole]

I remember Carl Sagan saying that the faster you travel, the slower
time progresses for the travelers. Does this mean that the trip will
take 1 week for the craft's occupants, but when they arrive back
on Earth their children will be grown and the mother-in-law(s) will be
R.I.P.? -cwm

Originally posted by Keyhole
What I gather out of this (I may be wrong) is that the launch platform stays stationary and shoots a laser at the other spacecraft propelling it forward.

How accurate could they keep this laser to keep propelling the other spacecraft and after what distance would it become (if it would) to weak to push the "spacecraft?

[edit on 11/9/07 by Keyhole]

You are correct. And therein lies the problem. Even if it maintained its cohesion enough to propel it to half the distance of Mars (which is what it would need to do to get it up to proper speed), then how to the astronauts get back? Unless there is another PLT system in Martian orbit, it doesn't do a damn bit of good. And even if you brought one there, the mirror is on the back of your spacecraft so where would your rocket thrusters go to propel you off of the Martian surface to get you back in space?

This sounds like a no-go technology for Earth-Mars transit. The moon might be a possibility though, since the distance isn't very far to send a PLT unit. Then again, we already have rocket technology to get us to the moon in 3 days, so why would we need the PLT for an Earth-lunar transit?

Poor Dr. Bae
Will be sent on his way
So all he can say
is "Have a nice day!"


[edit on 9/12/2007 by pjslug]

Originally posted by pjslug
You are correct. And therein lies the problem. Even if it maintained its cohesion enough to propel it to half the distance of Mars (which is what it would need to do to get it up to proper speed), then how to the astronauts get back? Unless there is another PLT system in Martian orbit, it doesn't do a damn bit of good. And even if you brought one there, the mirror is on the back of your spacecraft so where would your rocket thrusters go to propel you off of the Martian surface to get you back in space?

That sounds about right I think. Send a PLT system to Mars the conventional way before you start your manned mission, or alternatively have the system attached to your craft and deployed into orbit upon its arrival to Mars. Also I doubt cohesion would be too much of an issue, like you said as long as it gets them over halfway there nature will do the rest.

I say combine this system as a speed boost for the journey to Mars with conventional rocket/thruster systems and we've got a real chance of making it.

The main issues is power. We're going to have a put a few Nuclear reactors into space for this one, and as we know the Hippies will scream planet rape at that. Personally I think the chance of a little rad-dosing if something was to go wrong is nothing compared to the future of humanity.

reply to post by ferretman2


Good points, ferretman. Now they will have to come up with a deflector shield technology, or at the very least a very good ablative armour.

Damn! I just can't stop quoting Star Trek terminology

Originally posted by Keyhole
How would you get back?

There'll be no need to get back after ploughing into the Martian surface at about 200,000 mph.

Well, no. Actually, we would need to place another "laser" in orbit around Mars. We could then use this "laser" to both decelerate and get back.

Has anyone else noticed that not much has been mentioned about keeping this laser stable in orbit.

Conventional thrust was mentioned, but uhhhh. Okay, I don't think there is enough fuel to push back for the entire time the laser is firing. That's the whole reason they're thinking about using lasers. You've just taken the conventional rocket and moved it a step back from the craft it's propelling.

Then there was mentioned the possibility of firing the laser both at the spacecraft and in the exact opposite direction. Well, that sounds wonderful, right? Equal "laser beam" thrust in both directions.
No, I don't think so. There are supposed to be mirrors on both the spacecraft and the laser. There is also supposed to be gain medium in between the spacecraft and the laser. Well, that amplifies the thrust by, what did the article say, about 3500 times? That would mean the thrust on one end would be way more powerful than the thrust on the other and the laser's orbit couldn't stay stable.

**ethnic slur removed**

[edit on 12/9/2007 by Umbrax]

only problem i see with the increase in thrust, is the fact that it always makes space debris in front of the craft move even quicker towards it! They would need to come up with some sort of shield panels to deflect this sort of thing, even the smalled piece of rock out there could do a huge amount of damage...

When i read a thread i try to read all the posts so i do not say the same as somone else or ask the same question.

It also helps me understand what the train of thought that is on that thread..

I mentioned on page 2 about rocks and dust and stuff and the fact that traveling at that speed would need a extremely fast nav computer! do we have one ??

Kind Regards

Git

Hmmm, seems like everyone is bent on a manned mission. How about an unmanned mission, a one way trip? Would be just as useful to begin with. G forces, minor particle collisions would then be a lesser issue, no?

I red a little of the data, and if someone could answer it would be great... so here goes, does it burns something? Like oil or ? What's the power source?

In the future, it would be great to have many corporations doing contests, the fastest trip to mars, then the first trip to pluto... things like that, would be great.

reply to post by Sunsetspawn


Maybe the laser can be placed at the Langrangian points?

Or perhaps a combination of that and a geostationary orbit. The lasers in orbit will nudge it to the Sun-Earth L1 or L2 points where it will then be routed towards Mars. Likewise but in reverse the the craft will be decelerated and deflected by the the Sun-Mars L1 or L2 points towards a laser in geosynchronous orbit with Mars.

Just tossing ideas around.

reply to post by 2believeor0


It seems like an unmanned space mission would seem like the best mission for this technology (if it ever works out). Just accelerate the craft and send it on its way.

Maybe it could even catch up to Voyager 1, which has a 30 year and a 6.3 billion mile head start!

It does seem like you would still always have to have some sort of thrusters on the craft if you wanted to manuever around planets, moons, or whatever to get more information and pictures though.

Originally posted by Sunsetspawn
ethnic slur removed

Come on man, that's not cool. No need for racial remarks, please.

[edit on 12/9/2007 by Umbrax]

Wow, is all I can say. I find it ironic how Arthur C. Clarke predicted massive spaceships tking us to Jupiter in 2.5 years in 1982 when he came out with the book 2010. Funny to think we still have the same dang cramped ships as then but we might be able to make that trip in say 5 weeks. good try on the predicting but he may have mixed it up a little.

reply to post by Vitchilo


My guess is that it's just battery power, or maybe in the future nuclear, but electricity none the less. I think what they describe is a laser fired from the back of the engine at a reflecting point and the bounce of the photons creates thrust. At least thats how I saw it. Anyone else?

Originally posted by completenuttergit
I mentioned on page 2 about rocks and dust and stuff and the fact that traveling at that speed would need a extremely fast nav computer! do we have one ??

Kind Regards

Git

i was thinking about this, assuming we had sensors good enough & fast enough computers to make a 'nav computer'.

could we actually react fast enough to avoid a collision?

(not knocking the idea, i love starwars too)

i never understood this bit, surely by the time you detect an object in the way it'll be like bang!! what the feck was that!! RED ALERT !!!!

reply to post by Capt DogToffee


I doubt a navigational computer would actually help with collision avoidance by much. Besides, how would the craft change direction? The laser has to be bounced off a stationary target. Even if they put in manoeuvring thrusters, the craft would be moving at such a high speed that any change in direction would have a wide arc. Meaning they'd have to detect obstacles way out in the distance.

reply to post by Beachcoma


So in that case if there was something just happening along as were belting through the solar system , its good night nurse isnt it ?

Sorry this sounds like a no go !!

Rgds
Git

reply to post by completenuttergit


I beg to differ. We've sent probes without incident before. You've got to remember that space is huge. Even the distance between two particles in the interplanetary medium is large.

But for protection against micrometeorites, we could always have some sort of armour or shield, like I mentioned in my previous post. Larger obstacles could no doubt be spotted from afar, or at the very least blown out of the way. Maybe.

[edit on 13-9-2007 by Beachcoma]