Dr. Deborah Brosnan, a climate and ocean scientist, predicts that Earth could eventually become uninhabitable for humans given the grave state of the planet
Solar sailing doesn’t require fuel, and can be truly solar powered. The IKAROS probe is a great example of this, and it was launched quite a while ago already. My favourite part of this probe was the liquid crystal panels that could change brightness and darkness electrically in order to steer by creating a differential absorption/reflection of sunlight. Clever stuff. It’s basically a steerable continuous thrust system that tacks against sunlight.
Probably you’d still want some RCS thrusters for faster reaction times in a pinch. And reaction wheels are “free” in terms of fuel, so there is likely some upper bound to lifetime. But not as bad as normal spacecraft.
Long short: RCS thrusters are probably still useful, but may not necessarily need to be the primary means of station keeping.
Clever stuff. It’s basically a steerable continuous thrust system that tacks against sunlight.
Very clever, and very useful. Though probably not useful for this case. The solar pressure/wind will enact a constant normal force on the orbit of any craft at L1. So to maintain stable orbit (from my understanding) you will need to counteract that with a constant antinormal force, or else you’ll get pushed out of L1 and then go flying off.
I know on Earth you can sail more or less directly into the wind with a sail boat using clever geometry, but I’m not so sure that is possible when orbits are involved. That’s the limit of my KSP based knowledge of orbital mechanics lol.
There’s also some untested methods that could potentially work here,
I have to disagree with the first two you listed. The electrodynamic tether would slow down the craft and knock it out of L1 orbit. If I’m understanding, it’s the space equivalent of regenerative breaking. The magnetic sail would esentially have the same problem as the solar sail.
The bussard engine would definitely work, assuming the basic principle of the engine itself works. Though, I’m not sure if it would collect enough hydrogen when placed at L1. A very neat concept though, one I’d like to see happen!
Long short: RCS thrusters are probably still useful, but may not necessarily need to be the primary means of station keeping.
If we’re using today’s technology, they’d almost certainly be the primary means. But in this hypothetical future you may be right.
So to maintain stable orbit (from my understanding) you will need to counteract that with a constant antinormal force, or else you’ll get pushed out of L1 and then go flying off.
You’re absolutely right, assuming the craft is on the L1 saddle point. The craft can, however, sit slightly sunward of the saddle point in a halo orbit. It wants to fall towards the sun (and enter a solar orbit) due to being on that side of L1, but you set it in the position it needs to be to balance the force of sunlight. There will be quasi-stable points in a halo orbits around the sun-facing side of L1 which could sustain a whole lot of these buggers.
KSP is great, but it only does two body physics (unless you’re using the Principia mod – never tried it). So you cannot simulate things like lagrange points there. The patched conics are a great first order teaching tool though, and KSP is great for that!
There will be quasi-stable points in a halo orbits around the sun-facing side of L1 which could sustain a whole lot of these buggers.
I’ll take your word for it then.
KSP is great, but it only does two body physics (unless you’re using the Principia mod – never tried it). So you cannot simulate things like lagrange points there.
Would have been a nice addition to KSP 2 if they hadn’t fucked it up. I’ll check out that mod at some point though.
That only works with ion thrusters, which are extremely expensive IIRC. But even they need fuel.
Most satellites that are that far out still use RCS thrusters with reaction wheels. But solar power only helps so much with that.
That’s gonna get costly very quickly. I doubt there is the political will to do this.
Solar sailing doesn’t require fuel, and can be truly solar powered. The IKAROS probe is a great example of this, and it was launched quite a while ago already. My favourite part of this probe was the liquid crystal panels that could change brightness and darkness electrically in order to steer by creating a differential absorption/reflection of sunlight. Clever stuff. It’s basically a steerable continuous thrust system that tacks against sunlight.
There’s also some untested methods that could potentially work here, like eletric tethers in the sun’s magnetic field – this stuff: https://en.wikipedia.org/wiki/Electrodynamic_tether – although I’m not aware of anyone that has done this calculation in the context of sunshields. And further outside the box, magnetic sails: https://en.wikipedia.org/wiki/Magnetic_sail or even this craziness https://en.wikipedia.org/wiki/Bussard_ramjet#Dyson_swarm-based_stellar_engine_(Caplan_thruster)
Probably you’d still want some RCS thrusters for faster reaction times in a pinch. And reaction wheels are “free” in terms of fuel, so there is likely some upper bound to lifetime. But not as bad as normal spacecraft.
Long short: RCS thrusters are probably still useful, but may not necessarily need to be the primary means of station keeping.
Very clever, and very useful. Though probably not useful for this case. The solar pressure/wind will enact a constant normal force on the orbit of any craft at L1. So to maintain stable orbit (from my understanding) you will need to counteract that with a constant antinormal force, or else you’ll get pushed out of L1 and then go flying off.
I know on Earth you can sail more or less directly into the wind with a sail boat using clever geometry, but I’m not so sure that is possible when orbits are involved. That’s the limit of my KSP based knowledge of orbital mechanics lol.
I have to disagree with the first two you listed. The electrodynamic tether would slow down the craft and knock it out of L1 orbit. If I’m understanding, it’s the space equivalent of regenerative breaking. The magnetic sail would esentially have the same problem as the solar sail.
The bussard engine would definitely work, assuming the basic principle of the engine itself works. Though, I’m not sure if it would collect enough hydrogen when placed at L1. A very neat concept though, one I’d like to see happen!
If we’re using today’s technology, they’d almost certainly be the primary means. But in this hypothetical future you may be right.
You’re absolutely right, assuming the craft is on the L1 saddle point. The craft can, however, sit slightly sunward of the saddle point in a halo orbit. It wants to fall towards the sun (and enter a solar orbit) due to being on that side of L1, but you set it in the position it needs to be to balance the force of sunlight. There will be quasi-stable points in a halo orbits around the sun-facing side of L1 which could sustain a whole lot of these buggers.
KSP is great, but it only does two body physics (unless you’re using the Principia mod – never tried it). So you cannot simulate things like lagrange points there. The patched conics are a great first order teaching tool though, and KSP is great for that!
I’ll take your word for it then.
Would have been a nice addition to KSP 2 if they hadn’t fucked it up. I’ll check out that mod at some point though.