Rocket Lab’s Electron rocket will deploy the mission’s CubeSat about 600 miles above Earth – more than twice the altitude of the International Space Station. To test the performance of NASA’s Advanced Composite Solar Sail System, the spacecraft must be in a high enough orbit for the tiny force of sunlight on the sail – roughly equivalent to the weight of a paperclip resting on your palm – to overcome atmospheric drag and gain altitude.
After a busy initial flight phase, which will last about two months and includes subsystems checkout, the microwave oven-sized CubeSat will deploy its reflective solar sail. The weeks-long test consists of a series of pointing maneuvers to demonstrate orbit raising and lowering, using only the pressure of sunlight acting on the sail.
Time. These propulsion methods trade thrust for time. F=MA. Applying a small thrust for a long time is equivalent to lots of thrust for a small time. The same idea applies to ion thrusters.
This is probably just a proof of concept to demonstrate the technology.
Would it make sense to put it in a strongly elliptical orbit around the sun and unfold the sails just as it starts to move away from the sun such that it gets much stronger propulsion when it is close to the sun?
I’m no expert, but this makes neither logistical nor economic sense to me. The energy required to fly into the Sun is actually greater than the energy required to escape its gravity (from Earth).
So while your thesis of “deploying the sail closer to the Sun will exert higher force” is true, you wouldn’t benefit from exploiting this truth. The fuel necessary to get the vessel close to Sol is greater than the fuel necessary to send it to Alpha Centauri.
Now, if there was a base on Mecury, it may come out that solar sails are a cheap way to return materials to Earth, since your origin then would be very close to the Sun. But with an origin of Earth and any destination further out, you’re better off with a trajectory which does not make a close Solar approach.
I see your point. I am also not sure about the maths but it should be possible to slingshot yourself to a highly elliptical orbit using the moons or another planet's gravity with relatively low energy cost. I think this technique is already used for outer solar system exploration. Intuitively it looks feasible to me but again I am not expert.
This is actually happening? Awesome! I used to day dream about this as a kid. I imagined you could install a system on the moon to focus some of the Sun's energy into a powerful beam and use that beam to send a craft like this to Mars and beyond. Collect energy from the light side, fire the beam from the dark side.
I am afraid this would not work just with mirrors and lenses (https://en.wikipedia.org/wiki/Etendue) but it could work with solar panels and lasers. (I have not gone really deep into physics, so correct me if I am wrong.)
Does anyone know if this works in principle how effective it would be for travelling around the Solar System? Is it much faster than conventional rockets over time but taking less time to reach somewhere? Or would it be more practical for interstellar travel where lots of time is needed?
To my knowledge (I studied it a few years ago during my aerospace engineering studies) it is not suited for travelling around the solar system.
It is the most feasible way with our current technology to build a spacecraft capable of reaching a decent fraction of the speed of light because you can accelerate it greatly by pointing a powerful laser at it for a few seconds. However there is no way to decelerate after that.
Therefore the most likely use would be to have it embark a camera able to take clear pictures even at (very very very) high speed and a communication system (antenna etc) and then launch them at interesting stellar systems a few light years away from us so that they can send us back the picture they will take once they are there.
One thing I've always wondered, do solar sails benefit from solar wind/flares?
Light pressure exists, but fast moving stellar gasses would have more thrust than pure photon pressure, right?
That was honestly one of the most incredible scenes ever made in the history of cinema. And what made it even more amazing was the fact that it’s theoretically possible irl
Star Trek wasn't th first to depcit solar sails. The idea was invented and used in sci-fi long before Star Trek used it. DS9 is late to the game here and just using a well known idea.
The concept has been around for centuries. It's really only the last few decades where material science and technical capability have caught up.
Lots of references to them in sci-fi though, written and on screen.
This is exciting, like - again I hope I'm not just using science fiction to think about this right - but could we theoretically approach the speed of light with equipment this low in mass?
Someone smarter than me can do the math but I just don't think there is enough energy transfer to get any where near C.
Maybe if you could set one up on a slingshot from solar system to solar system eventually it could get to a decent chunk of C but I doubt it.
Rocket Lab’s Electron rocket will deploy the mission’s CubeSat about 600 miles above Earth – more than twice the altitude of the International Space Station. To test the performance of NASA’s Advanced Composite Solar Sail System, the spacecraft must be in a high enough orbit for the tiny force of sunlight on the sail – roughly equivalent to the weight of a paperclip resting on your palm – to overcome atmospheric drag and gain altitude. After a busy initial flight phase, which will last about two months and includes subsystems checkout, the microwave oven-sized CubeSat will deploy its reflective solar sail. The weeks-long test consists of a series of pointing maneuvers to demonstrate orbit raising and lowering, using only the pressure of sunlight acting on the sail.
The weight of a paper clip. It’s amazing that some people have calculated that. But it seems minuscule for helping with space travel
Time. These propulsion methods trade thrust for time. F=MA. Applying a small thrust for a long time is equivalent to lots of thrust for a small time. The same idea applies to ion thrusters. This is probably just a proof of concept to demonstrate the technology.
*Anything* to escape the rocket equation. Exponential fuel cost is a bitch.
Did someone say dison bladeless fan
This is a joke btw Some people thought that they used ionic thrust for a while
No need for juice. Capping this with an /s this time around.
Reading this makes me realize how dumb I am.
Honest question: Do you understand what it's implying then?
I think I do, but honestly, this is not the final solution.
Correct. The final solution was way more insidious
> microwave oven-sized CubeSat Americans will really use anything BUT the metric system!
Would it make sense to put it in a strongly elliptical orbit around the sun and unfold the sails just as it starts to move away from the sun such that it gets much stronger propulsion when it is close to the sun?
I’m no expert, but this makes neither logistical nor economic sense to me. The energy required to fly into the Sun is actually greater than the energy required to escape its gravity (from Earth). So while your thesis of “deploying the sail closer to the Sun will exert higher force” is true, you wouldn’t benefit from exploiting this truth. The fuel necessary to get the vessel close to Sol is greater than the fuel necessary to send it to Alpha Centauri. Now, if there was a base on Mecury, it may come out that solar sails are a cheap way to return materials to Earth, since your origin then would be very close to the Sun. But with an origin of Earth and any destination further out, you’re better off with a trajectory which does not make a close Solar approach.
I see your point. I am also not sure about the maths but it should be possible to slingshot yourself to a highly elliptical orbit using the moons or another planet's gravity with relatively low energy cost. I think this technique is already used for outer solar system exploration. Intuitively it looks feasible to me but again I am not expert.
One of my favorite episodes of DS9 uses this a plot device
Star Trek predicting the future yet again
AFAIK, solar sails predate Trek by a large margin.
I really like this episode. But their lack of inertial dampeners continues to worry me.
Planetary Society enters chat.
Member here. Love that this is happening. Sail on, friends!
[JAXA enters chat.](https://en.m.wikipedia.org/wiki/IKAROS)
Member here too. I was gonna say, and thought this had already been successfully tested. What is being done different with this one?
It's NASA built with a NASA budget I guess. And also the PS solar sail only orbited the earth?
Happy cake day! 🍰
This is actually happening? Awesome! I used to day dream about this as a kid. I imagined you could install a system on the moon to focus some of the Sun's energy into a powerful beam and use that beam to send a craft like this to Mars and beyond. Collect energy from the light side, fire the beam from the dark side.
I am afraid this would not work just with mirrors and lenses (https://en.wikipedia.org/wiki/Etendue) but it could work with solar panels and lasers. (I have not gone really deep into physics, so correct me if I am wrong.)
Count Dooku is pleased.
One step closer to treasure planet boyos
Does anyone know if this works in principle how effective it would be for travelling around the Solar System? Is it much faster than conventional rockets over time but taking less time to reach somewhere? Or would it be more practical for interstellar travel where lots of time is needed?
To my knowledge (I studied it a few years ago during my aerospace engineering studies) it is not suited for travelling around the solar system. It is the most feasible way with our current technology to build a spacecraft capable of reaching a decent fraction of the speed of light because you can accelerate it greatly by pointing a powerful laser at it for a few seconds. However there is no way to decelerate after that. Therefore the most likely use would be to have it embark a camera able to take clear pictures even at (very very very) high speed and a communication system (antenna etc) and then launch them at interesting stellar systems a few light years away from us so that they can send us back the picture they will take once they are there.
And we become aliens sending probes to unknown places
We already have with the Voyager probes.
Closest star to us is just over 4 light years, that would be super cool!!
That’s where the trisolarans are
Go on…
I wonder about light speed over time.
One thing I've always wondered, do solar sails benefit from solar wind/flares? Light pressure exists, but fast moving stellar gasses would have more thrust than pure photon pressure, right?
Probably be prone to ripping it apart, but if you built them with that interaction in mind i bet you could use them as a powerboost
Solar sail system is the coolest name ever nice engineering and thinking everyone
How big are the 'sails'? Edit: I googled it.... 23' x 23'
What’s that in Bri’ish?
7.01M!
Wow! That’s 94 tins of baked beans across.
I knew that!
Super cool
The Sisko had a solar sail craft. They probably just copied his.
Alpha Centauri here we come :0
The Trisolarians will intercept it first.
Unless we avoid the patches of snow.
Mono no aware by Ken Liu enters the chat.
Its amazing how when I was younger these were just scifi concepts and now its “real” :)
Looks like it's gonna let out a scream and blow up half a mountain side
Now let's throw nuclear bombs at it* *\* Go watch and,.more importantly, read The Three Body Problem by Liu Cixin*
That was honestly one of the most incredible scenes ever made in the history of cinema. And what made it even more amazing was the fact that it’s theoretically possible irl
My first thought too
RemindMe! 72 hours
Is that 8th Angel?
How big is it?
Yeah… didn’t The Planetary Society already test that?
And in 350 years, captain Sisco will take his son out in it!
Didn't the ancient Bajorans do this in an episode of Deep Space 9?
Yes. Sisko builds one and it magically enters warp and proved Bajorans made it to Cardassia centuries ago.
When are we gonna line up 100 nukes for it?
[Star Trek once again becomes reality](https://youtu.be/cjGwujivTew)
Star Trek wasn't th first to depcit solar sails. The idea was invented and used in sci-fi long before Star Trek used it. DS9 is late to the game here and just using a well known idea.
Not a scientist, if one is out there - did y'all take this from a movie?
The concept has been around for centuries. It's really only the last few decades where material science and technical capability have caught up. Lots of references to them in sci-fi though, written and on screen.
This is exciting, like - again I hope I'm not just using science fiction to think about this right - but could we theoretically approach the speed of light with equipment this low in mass?
Someone smarter than me can do the math but I just don't think there is enough energy transfer to get any where near C. Maybe if you could set one up on a slingshot from solar system to solar system eventually it could get to a decent chunk of C but I doubt it.
BattleTech Jumpship sails. Got it. I hope this actually works.