Laser-sail chips as first interstellar probes

[Ember12]

So far, pretty much all of the discussion about interstellar travel has been about fusion drives.  But there's another sort of spacecraft that can make the journey, which are tiny chips attached to a lightweight reflective sail.  If you fire a heckuva powerful laser at the sail, you can get the chip going extremely fast.  The Breakthrough Starshot initiative proposed sending a fleet of these at 20% the speed of light to the Alpha Centauri system, which would take only 20 years, with technology that could be developed in only a few decades.

In KSP2, these could represent an early-tech-tree method of sending unmanned starships.  The ships could be somewhat larger than computer chips, and this would only require a larger sail and "MOAH BOOSTAHS LAZAHS!"  These probes could obtain low-definition images of the planets they pass, as well as (more usefully) rough estimates of gravity, and maybe atmosphere density, which could be used to inform the design of later colony ships.

[t_v]

5 minutes ago, Ember12 said:

These probes could obtain low-definition images of the planets they pass, as well as (more usefully) rough estimates of gravity, and maybe atmosphere density, which could be used to inform the design of later colony ships.

This is why I think that discovery of other planets should be quite in-depth, so that sending missions to discover preliminary facts about a planet is actually something you might want to spend time on. I’d love to see solar sails (photon sails sounds cooler and encompasses the full meaning of the technology) because you can really only accelerate in one hemisphere of directions, and that sounds like a fun challenge. 
 

(plus, giant lasers are fun to play around with)

Edited August 8, 2022 by t_v

[The Aziz]

I believe it was mentioned as out of the question, as it would require ground based propulsion. With planetary movement constantly simulated, it would mean pauses in acceleration, unless you build multiple lasers. Also, would you have to aim them manually? There's many questions when it comes to external means of propulsion.

Solar sails are more probable, but again, I believe they weren't planned for release.

[Ember12]

33 minutes ago, The Aziz said:

I believe it was mentioned as out of the question, as it would require ground based propulsion. With planetary movement constantly simulated, it would mean pauses in acceleration, unless you build multiple lasers. Also, would you have to aim them manually? There's many questions when it comes to external means of propulsion.

What I had in mind was a large orbiting laser, so that it could keep its orientation.   Aiming manually would not be accurate enough, and you'd have to have something to ensure the sailcraft was properly centered.  It could be a sort of mini-VAB, where you send up chips and sails, build the sailcraft at the laser, select a target, then the laser orients toward it.  The sailcraft spawns right in front of the laser, and away you go.

Of course, the game mechanics needed to do all this would be quite specialized and probably don't exist right now, so it might not be worth all the programming effort.

39 minutes ago, The Aziz said:

Solar sails are more probable, but again, I believe they weren't planned for release.

Isn't the purpose of this forum to suggest things that aren't planned for release right now?

[kspnerd122]

Breakthrough starshot probes are accelerated at over 10g, so earth rotating isnt much of an issue

[Ember12]

44 minutes ago, kspnerd122 said:

Breakthrough starshot probes are accelerated at over 10g, so earth rotating isnt much of an issue

By my calculation, to reach the planned speed of 0.2c, you would need to accelerate at 10g for about a week, so Earth's rotation could definitely be an issue.  But I had not researched this enough, and it turns out that you need a 100-gigawatt laser pushing the thing the whole way.  That much power might be far outside KSP2's engineering scope.

[Pthigrivi]

I think I remember Nate mentioning things like this and solar sails as a potential expansion idea. 

[Bej Kerman]

23 minutes ago, Pthigrivi said:

I think I remember Nate mentioning things like this and solar sails as a potential expansion idea. 

Do you have a link for this?

[Pthigrivi]

1 hour ago, Bej Kerman said:

Do you have a link for this?

I think it was an early interview with shadowzone? Lemme dig…

Edit: Aagh. Im sure I heard it somewhere but I’ve got a big presentation I need to wake up early for. Halp? Like when they were crediting Scott Manley for suggesting a boat launch?

Edited August 15, 2022 by Pthigrivi

[Superluminal Gremlin]

On 8/14/2022 at 12:53 AM, Ember12 said:

at 10g for about a week

You could do it on the moon, and as the moon doesnt rotate, it only orbits. Then you can just have it on one side an continuously aim in at the chip.

[Ryaja]

2 minutes ago, TKMK said:

You could do it on the moon, and as the moon doesnt rotate, it only orbits. Then you can just have it on one side an continuously aim in at the chip.

It does rotate, it's rotational period is the same as it's orbital period. So it appears as if it does not rotate from earth.

Edited August 15, 2022 by Ryaja

[Superluminal Gremlin]

dammit.

maybe be would use a polar orbiting laser, so it can constantly laser the chip?

Edited August 15, 2022 by TKMK
spelling error

[t_v]

5 hours ago, TKMK said:

dammit.

maybe be would use a polar orbiting laser, so it can constantly laser the chip?

Or, hear me out, have multiple lasers on the planet. Any laser you put in orbit is going to push itself as well as the chip, so you would have to put in a lot of energy to maintain the orbit. Also, since you only need to accelerate for a few weeks, on the moon you could get a fair amount of time from one day. 

[Ember12]

7 hours ago, t_v said:

Any laser you put in orbit is going to push itself as well as the chip

Given that the sailcraft only weigh a few grams, this thrust could easily be compensated for with a small engine on the laser.

[t_v]

57 minutes ago, Ember12 said:

Given that the sailcraft only weigh a few grams, this thrust could easily be compensated for with a small engine on the laser.

I realize now that the thrust numbers we’re looking at aren’t actually that large, and that all you need is enough fuel to continuously burn while the sail craft is accelerating, which isn’t necessarily that much. 

[Ryaja]

12 hours ago, t_v said:

Any laser you put in orbit is going to push itself

You just do it in the opposite direction to, either by shooting into nothing or having a mission going in the opposite direction.

12 hours ago, t_v said:

have multiple lasers on the planet

You could also have a sort of relay network like thing where there is always a laser to shoot the craft

Edited August 15, 2022 by Ryaja

[Bej Kerman]

19 hours ago, TKMK said:

the moon doesnt rotate

It does, once an orbit.