Mars in 3 days

[Spaceception]

NASA recently did research on a propulsion system that could get humans to Mars in as little as 3 days for a 100 kg probe, and a Manned (Much heavier) spacecraft in a month.

Now, we do know this tech exists, like Starwisp, but if they can scale up the lasers (And power) needed (With either massive solar panels, or fusion reactors), we could send a probe to Proxima Centauri by the end of the century, and have it get there in as little as 40 years.

Now, there's no telling of whether this would get enough funding (Or any funding), but if it did, we could have a very fast propulsion system that could allow us to explore to solar system quickly.

So what do you think about it? And do you guys think building something like this would be worth it?

[p1t1o]

There was a discussion of this exact thing at the thread called "sedna probe" but to paraphrase my two cents -

For reference, for an interstellar trip, we're talking a laser in the range of thousands to tens-of-thousands of GigaWatts. That starts at aroundabout a billion square meters of solar panel (at 1au) if you want to power it that way.

Nice idea but I don't think we can do it yet, apart from my main worry, which is basically an ultradeath Ray in orbit, when was the last time a government successfully executed a 40year project?

Technically feasible, but biggest problems are probably socio-political. We aren't even sure what's at the edge of our own system yet, let's give it a few generations.

[Spaceception]

23 minutes ago, p1t1o said:

There was a discussion of this exact thing at the thread called "sedna probe" but to paraphrase my two cents -

For reference, for an interstellar trip, we're talking a laser in the range of thousands to tens-of-thousands of GigaWatts. That starts at aroundabout a billion square meters of solar panel (at 1au) if you want to power it that way.

Nice idea but I don't think we can do it yet, apart from my main worry, which is basically an ultradeath Ray in orbit, when was the last time a government successfully executed a 40year project?

Technically feasible, but biggest problems are probably socio-political. We aren't even sure what's at the edge of our own system yet, let's give it a few generations.

I didn't even know you guys were discussing that, I looked up photonic propulsion, but nothing came up, so I assumed that it hadn't discussed (Not much at least).

[magnemoe]

As I understand this system work by reflecting the light between the probe sail and one around the laser and back getting far more bangs for the buck, one problem is to keep the beam bouncing while the probe accelerates away. 

second is that this acceleration has to be done fast as in 20.000 g, yes this works in cannons, however they have barrels and shoot thick bodied shells, any irregularities in the beam will rip the probe in pieces, an 0.1% error gives an 200 g force. 
It will probably work better for heavier stuff accelerating slower but this require constant beams and cooling of lasers. 

[p1t1o]

13 minutes ago, magnemoe said:

As I understand this system work by reflecting the light between the probe sail and one around the laser and back getting far more bangs for the buck, one problem is to keep the beam bouncing while the probe accelerates away. 

second is that this acceleration has to be done fast as in 20.000 g, yes this works in cannons, however they have barrels and shoot thick bodied shells, any irregularities in the beam will rip the probe in pieces, an 0.1% error gives an 200 g force. 
It will probably work better for heavier stuff accelerating slower but this require constant beams and cooling of lasers. 

20000g? As in force-of-gravity? I havnt seen that figure anywhere, that's twice as hard as the average rifle bullet...

30000GW gets you 20000g for a 1kg probe, and its going to have to be sturdy!

And the amount of heat that the laser will produce...yeah I don't think it will happen this way anytime soon.

[Stargate525]

Okay, Mars in three days. Cool.

How the hell are you going to STOP?

[magnemoe]

3 hours ago, p1t1o said:

20000g? As in force-of-gravity? I havnt seen that figure anywhere, that's twice as hard as the average rifle bullet...

30000GW gets you 20000g for a 1kg probe, and its going to have to be sturdy!

And the amount of heat that the laser will produce...yeah I don't think it will happen this way anytime soon.

http://www.deepspace.ucsb.edu/wp-content/uploads/2015/04/A-Roadmap-to-Interstellar-Flight-15-o.pdf
Artillery gives 20000g, smart shells can survive this, problem is that the probe is not an shell in an barrel.
They talk about 80GW for an full scale system, 

[AngelLestat]

I always look up for anything related to solar panels or beamed propulsion, so I am quite inform of the difficulties and the advantages for each application.
For fast interplanetary travel, I would choose a microwave sail with some special layer cover that when heat up it will work as propellent.
But the idea that I like more of all sail applications.. is a simple solar sail.
These can be made in space very cheap and go anywhere in the solar system.
They could also reach interstellar speeds to reach alpha centauri in 50 years mastering the material and technology with a close dive in the sun.

[Bill Phil]

I think that Project Orion is an equally capable propulsion system, except it pushes hundreds of tons to Mars.

[fredinno]

5 hours ago, magnemoe said:

http://www.deepspace.ucsb.edu/wp-content/uploads/2015/04/A-Roadmap-to-Interstellar-Flight-15-o.pdf
Artillery gives 20000g, smart shells can survive this, problem is that the probe is not an shell in an barrel.
They talk about 80GW for an full scale system, 

Yeah, only problem is the acceleration is continuous, and eventually, you need to stop to turn around and decelerate.

[Mitchz95]

6 hours ago, Stargate525 said:

Okay, Mars in three days. Cool.

How the hell are you going to STOP?

I suppose we'll have deployed a similar station in Mars orbit to slow incoming vessels in the same manner.

[Stargate525]

2 minutes ago, Mitchz95 said:

I suppose we'll have deployed a similar station in Mars orbit to slow incoming vessels in the same manner.

And the power on Mars for such a laser is coming from...?

[Spaceception]

6 hours ago, Stargate525 said:

Okay, Mars in three days. Cool.

How the hell are you going to STOP?

Good question Maybe it'll only be ideal for flyby probes, and interstellar probes

[fredinno]

13 minutes ago, Spaceception said:

Good question Maybe it'll only be ideal for flyby probes, and interstellar probes

Even those need to slow down to take useful data.

[Stargate525]

8 minutes ago, fredinno said:

Even those need to slow down to take useful data.

If you're talking coming into a system at interstellar speeds, you could probably bleed some speed off by clever and numerous flybys. Or massive aerobraking.

[kerbiloid]

8 hours ago, Stargate525 said:

Okay, Mars in three days. Cool.

How the hell are you going to STOP?

"Brakes are invented by a coward".

But once in 1980s I have read a large article about similar projects (American or British - I don't remember): "Starlight" and "Super Starlight" interstellar laserships. I can't google them up, sorry. In 1980s they were in a paper.

An unmanned spacecraft (large mirror disk) propelled with a laser beam pressure. A mighty laser orbits the Sun and continuously accelerates the mirror disk to the Barnard Star.

The former of them ("Starlight") would do a non-stop fly-by.
But the latter (and bigger) "Super Starlight" - was not only to stop, but also to return back.

Idea was: the craft consists of three stages - concentric mirror parabolic disks: as a giant flat Hanoi tower.
All of them are miror-like from the Sun side, but the 2nd and 3rd stage disks are also mirrors from the target side.
On start they are looking as one giant mirror, of course, Laser beam pressure simply accelerates this thing in the Barnard star direction.

Once this thing reaches a deceleration point, the widest disk (say, it's the 1st stage) is separated and slowly moves away in advance,
Laser beam still presses them all, but as the 1st stage area is much greater than the 2nd one, the laser beam parabolically reflected  from the 1st stage, presses on the 2nd+3rd stage from the rear side with greater force than it presses its subsolar side.
So, the 1st stage continues its acceleration, but 2nd+3rd stages decelerate until it completely stops near the destination point.

Then 1st stage is no more required (anyways, it's already far from the main craft) and says farewell.

The mighty near-Sun laser still continues its work.
Now the second stage disk separates from the 3rd stage - and all repeats: the subsolar side of the 2nd stage works as a parabolic reflector than concentrates the beam on the rear side of the 3rd stage.
So, the 2nd stage accelerates and flies away - in chase of the 1st stage, while the 3rd stage runs back to the Sun.

Mighty laser stops, 3rd stage returns back to the Solar System, trtansferring scientific data.

When the 3rd stage reaches the Solar Sytem, the laser starts again and simply decelerates the 3rd stage.

Re-entry probe with the interstellar matter examples returns to the Earth.

 

So, probably somebody in NASA had found his granny's old magazines, took a look and now we would await for an amazing new series of animations on youtube.
 

Edited February 27, 2016 by kerbiloid

[DerekL1963]

7 minutes ago, kerbiloid said:

But once in 1980s I have read a large article about the similar projects (American or British - I don't remember): "Starlight" and "Super Starlight" interstellar laserships. I can't google them out, sorry. In 1980s they were in a paper.

Sounds like something from the British Interplanetary Society - they have never been afraid to dream big and dream crazy.

[kerbiloid]

Pictured that Super Starlight project where they stop and return.

 

[Spaceception]

3 hours ago, kerbiloid said:

Pictured that Super Starlight project where they stop and return.

 

Ooooh, green Stars, I didn't know those existed

[Findthepin1]

In the book Aurora by KSR, they have a ship that goes to a super-Earth exoplanet and its Laythe-analog moon. They first accelerated out of Sol's system using a really big laser fired at them, sort of like what is being discussed here.

[Spaceception]

27 minutes ago, Findthepin1 said:

In the book Aurora by KSR, they have a ship that goes to a super-Earth exoplanet and its Laythe-analog moon. They first accelerated out of Sol's system using a really big laser fired at them, sort of like what is being discussed here.

I've heard of that book, I really want to read it!

Edited February 27, 2016 by Spaceception

[Nothalogh]

23 hours ago, Stargate525 said:

Okay, Mars in three days. Cool.

How the hell are you going to STOP?

Lithobraking, I assume 

[KAL 9000]

5 hours ago, Findthepin1 said:

In the book Aurora by KSR, they have a ship that goes to a super-Earth exoplanet and its Laythe-analog moon. They first accelerated out of Sol's system using a really big laser fired at them, sort of like what is being discussed here.

Link?

[Findthepin1]

Just now, KAL 9000 said:

Link?

There isn't a link it's an actual book.

[Spaceception]

49 minutes ago, KAL 9000 said:

Link?

http://www.amazon.com/gp/product/B00NERQRPI/ref=dp-kindle-redirect?ie=UTF8&btkr=1