Want To Reach Mars? New Tech Could Make The Trip In Three Days

[Dalisclock]

What ever happened to the EM drive that everyone thought would be the future of space travel?

I think it's still being hashed out in engineering/scientific circles.

 

[Something Amyss]

That addresses the outbound flight, which is great for any one way trips. A return trip is gonna be a much slower and will have to do things the old fashioned way. And again, slowing down from .3c is gonna have it's own issues because now there's a huge amount of d/v that needs to be canceled out. Unless the whole thing is geared towards planetary flybys, or the initial leg in a journey that has ramscoop tech and could take advantage of .3c speeds.

I'm cool with PoC. We'll get a better idea how feasible it actually it is.

.3c is for tiny ships with a sail of about a meter and equal payload. The point was power consumption. And line of sight, since you brought that up too. This is where we get the 3 days number, not the month number. upping it to 100kg reduces the speed to .2c in the same time period, already greatly slower (but still amazingly fast). The closest we get to a manned trip to Mars at this speed is mentioning a human-capable ship could reach .26c with a full day of propulsion, and it doesn't look like anyone's championing that.

I think we're addressing like four different issues at once, which makes it more difficult.

 

[Quellist]

Also the further you get from the sun the less 'solar wind' you get so its a case of diminishing returns. It's not really viable out of system as far as i understand.

Except this isn't about solar power, it's about lasers.

Crap, misread half of it then. Similar concept though with lightsails

 

[Pyrian]

I'm having real difficulty believing that you can accelerate a craft by 0.3c in 10 minutes without incinerating the sail (and the craft for that matter). Just because the energy is potentially there, doesn't mean you can harness it. And the longer it takes, the further you travel from the laser, while the further you travel from the laser, the larger your sail needs to be.

Still, the "not carrying your fuel" angle is huge; just because it'll probably never match the theory, doesn't mean it isn't worth pursuing the idea.

 

[BoogieManFL]

I find it incredibly amusing and interesting that we could be exploring our solar system with ships that are that much like the ships we explored the ocean with.

 

[Veylon]

In principle, you ought to be able to slow down by looping around Mars and then being hit by the laser when in the part of the loop that involves moving towards the Earth. This involves traveling slower than the escape velocity of Mars (5 km/s), meaning the trip can't possibly be completed in less than 130 days even at closest approach (56 million km) under ideal conditions.

First we send our robot army to set up, then the colonists arrive...

This is probably the most practical option. The robots don't care so much how long they take to get there. They can take the slow bus and get all the stuff ready for people to move in the second they arrive. If we want to be extra pie-in-the-sky, they could even set up a slow-down laser to save human transit time.

 

[Ravenbom]

(Important fact: Spaceships are massive.)

 

[Strazdas]

What do they do for the deceleration phase? Unless you stick a laser emitter in orbit around wherever you want to go, I guess you'd need to use more traditional chemical thrusters to actually slow down? How long a deceleration burn would it even take t slow down from 30% of lightspeed? I guess it's a gigantic improvement over having to burn up to cruising speed, and then also burn down to your orbital intercept, literally half the fuel required... but still.

I'm assuming if we ever apply this to interstellar travel we'd need to carry an extra laser setup with us during the trip. So that we have something on-site to beam the ship back home when it's done.

Definitely interesting, but I feel like there are some pretty big logistical issues to sort out.

could we not use Mars gravity for a swing around and then use same laser for deceleration till the craft goes into orbit/slow down enough to land? I mean sure it may add a bit more to those 3 days, but still not in terms of months.