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

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

NASA scientist Philip Lubin is working on a photonic propulsion system that could reduce Mars voyages from six months to three days.

The biggest hurdle to visiting Mars isn't technology, a lack of interest, or that its flowing water probably isn't drinkable - it's time. Flying a rocket to Mars is a six-month journey under ideal conditions, and returning to Earth poses its own problems. But what it we could reduce the trip from six months to three days? NASA's Philip Lubin believes it's possible, and is developing a laser-based photonic propulsion system to make it a reality.

"There are recent advances that take this from science fiction to science reality," Lubin says. "There is no known reason why we can not do this."

So let's figure out how this works. Right now, current rocket propulsion-systems are fuel-based, which requires huge volumes of fuel to move objects of greater mass. (Important fact: Spaceships are heavy.) So NASA's goal is to develop an electromagnetically-accelerated propulsion system powered by the momentum of light and radiation. This bypasses the drawbacks of current propulsion systems, and can theoretically be scaled up to spaceships of any size.

What's really incredible is this process already works - the Large Hadron Collider's superconducting magnets use a similar setup - we just haven't scaled it for starships. Lubin's system would attach giant sails to a spacecraft, which capture the photons from giant Earth-based lasers to move the vessel. Current calculations suggest a 100-kg robotic craft could pick up enough momentum to reach Mars in three days. A full-sized human spacecraft with photonic propulsion would take about a month, which is still remarkable.

There's just one problem: While photon propulsion is mass-efficient, humans are too heavy to send to distant star systems in a reasonable time. But we could still potentially explore planets in our own solar system, or send robotic craft to stars like Alpha Centurai. We should be seeing more details from Lubin's research soon, and I, for one, will be excited to see the results.

Source: Science Alert, via Fox

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I could have sworn somebody on the forums was talking about this sort of thing on another article about fusion power. It might have been me but could have been somebody else. Either way, great that they're considering this idea. Onwards to Mars, people!

Just a head's up, "exoplanets" by definition are outside our solar system. Mars is a planet, no prefix.

Ok, so silly question here. If this is a "pushing" type propusion system and the laser doing the pushing is on Earth....With these high velocities how is the craft going to slow down when it gets to its destination?? If it gets there in 3 days it will need to be decelerating for about half that time at least till it reaches its orbital insertion speed.

Corey Schaff:
I could have sworn somebody on the forums was talking about this sort of thing on another article about fusion power. It might have been me but could have been somebody else. Either way, great that they're considering this idea. Onwards to Mars, people!

So if I understand this correctly, this would work by planting a giant laser on the moon (or in Earth orbit), and using it to fill a sort of sail deployed by the spacecraft.

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.

Kenkurogue:
Ok, so silly question here. If this is a "pushing" type propusion system and the laser doing the pushing is on Earth....With these high velocities how is the craft going to slow down when it gets to its destination?? If it gets there in 3 days it will need to be decelerating for about half that time at least till it reaches its orbital insertion speed.

Mars is above us so we could use the lasers to accelerate and then use the suns gravity to slow down again. That's how most trips are done already since no one wants to waste fuel slowing down.

legend forge:
Just a head's up, "exoplanets" by definition are outside our solar system. Mars is a planet, no prefix.

Yup, that's fixed, thanks.

In other words it's another great theory, like warp engines.

Nurb:
In other words it's another great theory, like warp engines.

Oh no, not even remotely comparable to warpfield theory. Because this is actually technically feasible, doesn't require undiscovered exotic materials and parts of it have even already been put into practice. Last year for instance we had a successful test with a solar sail, so that's a step closer as well.

All that is quite the opposite of warp theory, oh which we only have a few extremely small and modest lab experiments.

rcs619:

Corey Schaff:
I could have sworn somebody on the forums was talking about this sort of thing on another article about fusion power. It might have been me but could have been somebody else. Either way, great that they're considering this idea. Onwards to Mars, people!

So if I understand this correctly, this would work by planting a giant laser on the moon (or in Earth orbit), and using it to fill a sort of sail deployed by the spacecraft.

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.

Excellent question. There actually might be a ways to use the laser back at earth to slow down the ship, surprisingly- when you're ready to decelerate you detach part of your sail (or deploy another), ahead ahead of the ship. Then you reflect light off the second sail- no longer attached to the ship- so it hits the ship's sail from the front, instead of behind.

Though, as you say, a ship that has to provide its own power and reaction mass to stop would still be t aa huge advantage over one that has to accelerate itself on the way there too.

Nurb:

In other words it's another great theory, like warp engines.

Not at all! Theoretical technologies like the Alcubierre drive that travel by "warping" space-time are wildly speculative and involve extremely exotic materials, like negative mass matter, that might not actually exist. A photon sail works on much more firmly established principles.

moose7:

Kenkurogue:
Ok, so silly question here. If this is a "pushing" type propusion system and the laser doing the pushing is on Earth....With these high velocities how is the craft going to slow down when it gets to its destination?? If it gets there in 3 days it will need to be decelerating for about half that time at least till it reaches its orbital insertion speed.

Mars is above us so we could use the lasers to accelerate and then use the suns gravity to slow down again. That's how most trips are done already since no one wants to waste fuel slowing down.

This is potentially a bigger problem, because the speed required to get to Mars at it's closest approach to the Earth is about a third the distance of the Earth to the sun. Basically a third of an AU. Just using the sun's gravity to slow that down would take a rather large overshoot of Mars. It'd take longer to slow and fall back than to get past Mars, meaning the trip would take a lot more than three days.

rcs619:

Corey Schaff:
I could have sworn somebody on the forums was talking about this sort of thing on another article about fusion power. It might have been me but could have been somebody else. Either way, great that they're considering this idea. Onwards to Mars, people!

So if I understand this correctly, this would work by planting a giant laser on the moon (or in Earth orbit), and using it to fill a sort of sail deployed by the spacecraft.

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.

The ground mounted laser it the first stage of the design. Current advances in laser weight to power output, if continued, will means thats is will be possible to build a 100kg spacecraft with a 3 GW laser on board. http://www.deepspace.ucsb.edu/wp-content/uploads/2015/04/A-Roadmap-to-Interstellar-Flight-15-h.pdf

Having read that article I'm somewhat suspicious about this paper. In part, it appears to be a description of a new nuclear weapons delivery system capable of hitting within in minutes at intercontinental range. Back in the bad old days of the cold war boths sides used to release papers that were outwardly fusion in stars but the really about fusion in warheads. If I were a nasty suspicious sort, I might think that this is in fact a message to the Russians.

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

Seriously though, very cool stuff. Eyes in the sky getting to where they're going faster is an excellent step forwards. Can't wait for the next one.

One thing not addressed(that I saw) was the energy requirements. To provide enough energy to both speed up that fast and slow down on the other end, especially via laser, seems like it wouldn't be feasible. Not to mention placement, because you'd have to keep LOS with the spacecraft to actually do it, which would be tricky once it gets to Mars(or wherever it's going).

And then there's the return trip.....

This kind of thing seems like it would be more useful for probes(especially when a return voyage is not required). and such then actual manned spacecraft

Fanghawk:

There's just one problem: While photon propulsion is mass-efficient, humans are too heavy to send to distant star systems in a reasonable time. But we could still potentially explore planets in our own solar system, or send robotic craft to stars like Alpha Centurai. We should be seeing more details from Lubin's research soon, and I, for one, will be excited to see the results.

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. In system though, especially the inner system it really could work

KyuubiNoKitsune-Hime:

This is potentially a bigger problem, because the speed required to get to Mars at it's closest approach to the Earth is about a third the distance of the Earth to the sun. Basically a third of an AU. Just using the sun's gravity to slow that down would take a rather large overshoot of Mars. It'd take longer to slow and fall back than to get past Mars, meaning the trip would take a lot more than three days.

It will take a lot more than three days, period. The headline is misleading. For a manned craft or anything of similar size, we're looking at a month. This partially solves the time issue.

From the original article:

But the real benefit of photonic propulsion comes over longer distances, where the spacecraft has more time to speed up, and could eventually take us outside our Solar System and to neighbouring stars.

To be clear, the system isn't designed to send humans across interstellar distances - first of all, robots are far better equipped for that mission, and secondly, we'd be far too heavy. Instead, Lubin proposes wafer-thin spacecraft that can get close to the speed of light.

And more explicitly:

A larger craft, like the kind humans might travel in, would take around a month to get there - one-fifth of the time it would take the Space Launch System (SLS), the world's most powerful rocket currently being developed to take us to Mars.

The article here kind of touches on it, but not explicitly.

Dalisclock:
One thing not addressed(that I saw) was the energy requirements. To provide enough energy to both speed up that fast and slow down on the other end, especially via laser, seems like it wouldn't be frasible.

They claim:

Lubin also explains that in the 10 minutes it will take to get the SLS into orbit, photonic propulsion could propel a spacecraft to an unheard-of 30 percent the speed of light - and it would also use a similar amount of chemical energy (50 to 100 gigawatts) to do so.

This would seemingly address the LOS issue, too. They don't need long-term line of sight.

Is this all true? I don't know, but apparently they were convincing enough to get a proof of concept grant from NASA. That's more than nothing, at least.

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.

Something Amyss:

This would seemingly address the LOS issue, too. They don't need long-term line of sight.

Is this all true? I don't know, but apparently they were convincing enough to get a proof of concept grant from NASA. That's more than nothing, at least.

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.

People should understand this is a process of exploring options. The 3 days thing is just an estimate of how fast they could get X amount of material there with Y power on the shortest route to Mars(a window which only happens once per 15 years and is not consistent), they will worry about details once this actually gets used.
If it gets used that is, many many crazy ideas are out there being explored but only the most reliably promising will get made, that is why we still burn tons and tons of fuel to get things up there, that shit is proven to work.

And I'm guessing you need to put that laser on the moon, our atmosphere becomes quite the hindrance once you talk long distance power, with some added concerns of self ignition.

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

Souplex:
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.

Dalisclock:

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.

Something Amyss:

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

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.

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.

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.

FalloutJack:
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.

Fanghawk:
(Important fact: Spaceships are massive.)

rcs619:

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.

 

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