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NASA to Launch Solar Sail
arbitraryaardvark writes "Physorg reports that NASA will launch a solar sail around the end of July. It'll be the first of its kind; a previous attempt blew up. It's a small proof-of-concept gizmo, not a full-on spaceyacht.
Solar sails operate on photon pressure from sunlight. They are well known to science fiction readers, otherwise not so much." C-net has coverage, too.
Sadly, my kids think a solar sail is something you put on a wooden ship to power the ion thrusters. Stupid disney and their stupid wooden ships in outer space...
Modding Trolls +1 inciteful since 1999
They are well known to science fiction readers, otherwise not so much
Excuse ME, I'm MORE than aware of what they are and I DON'T read science fiction.
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Star trek ftw!
+1 IDisagreeSoHeMustBeATrollOrAnAstroturferOrAShill
And in 50 years, the US Post Office will still be using said technology, while FedEx is traversing through worm holes.
You use this phrase Its the first of its kind. I do not think you know what it means.
And yes .. welcome to /. etc etc
I am Slashdot. Are you Slashdot as well?
Bajoran-One (ST:DS9 reference).
What velocity can it reach?
hopefully it will accelerate to a reasonable speed of a million miles a second and then aim it at the moon.. observing the impact for scientific data and whatever else.
I hope my grandkids can one day go outside to take a spin around Mars with their solar sails.
Still, the idea of a science-fiction object being realized in the real world is mighty interesting.
Maybe tomorrow they will think about warp drives.
As long as there are slaughterhouses, there will be battlefields.
From TFA: "And like a marine sail, a solar sail could also bring you home. You could use the solar sail to tack your vessel, making it travel "against the wind," back to Earth." I don't see how this would be possible.. sailboats can do this because of a keel which exerts force on the water, which cannot be done in the near vacuum of space. Or am i missing something?
v4sw4+6CShw4ln4pr3/4OPck3ma6u6Lw4Xm1l5DiNe4+7t4/5MRWb8HTen5a2Xs6MSr1p-5.75/-5.33g5/6GT hackerkey.com
I'd like to see a maglev train on an Andean mountain firing a ship into Earth orbit, which then deploys solar sails to catch the much more plentiful direct solar radiation to accelerate it away from the Earth. That seems like a better way to use the infrastructure we have on Earth, where at least 25-30% of the solar power is lost in the atmosphere and the air creates drag on the accelerated ship, and to use the microgravity and vacuum of space where it's easier to deploy light, flimsy solar collectors in the full sunlight.
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make install -not war
Still time to chip in your contribution towards the Planetary Society's second attempt to do a working solar sail.
Go to the moon. I have never been that big of a fan of going to the moon until japan showed that there is a lot of uranium up there. That makes it very different. That gives us power to build and launch nuke ships. Combine these with sails that can use a laser from the moon. Not a bad way to get high speeds.
I prefer the "u" in honour as it seems to be missing these days.
Yep, we'd best start working on the boost lasers, they'd be handy for the 1st Kzin war too.
The Physorg article notes: "And like a marine sail, a solar sail could also bring you home. You could use the solar sail to tack your vessel, making it travel "against the wind," back to Earth." But, I thought that do sail across the wind you need something to provide "lift" to counter the lateral force of the sail, which is provided in boats by a keel, or centerboard, or daggerboard, or a fin and rail on a windsurfer, or a skeg, etc. etc. Where's the counterforce in a solar sail in space?
My parents were married, you insensitive clod!
"Our chief engineer has high hopes that this will... if successful... generate power, to keep us alive." Oh and um... save the whales.
Maybe once they get the "Solar Sail" working they can focus their attention on getting that damn Dysan Sphere under construction. I would suggest getting a couple space elevators running to assist with construction.
"...a civilian some of the time, a soldier part of the time and a patriot all of the time." -Brig. Gen. James Drain
30-56-99 are correct. Limited 4 and 8 are missing.
And now you'll have two renegade programs running all over the system in a stolen simulation.
End of line.
"You're getting brutal, Sark. Brutal and needlessly sadistic."
"Thank you, Master Control"
-Sark and the MCP
Oh sweet Jesus, for crying out loud, STOP SAYING "not so much".
> It will travel to space onboard a SpaceX Falcon 1 rocket
Good luck with that one. They can't even get any time on the island because they have to beg & steal for government launch facilities.
A bit disappointing that the space station isn't being used for breathrough research like this. Instead it's busy enough keeping itself alive & selling Buzz lightyear promos.
On the cruise you will have peace of mind with a garden reeked of love.
For the sake of earnest unity on this voyage to infinity.
On the voyage to infinity, can't forget to take your soul.
Cause at the port you'll find no double sign.
Physics is like sex: sure, it may give some practical results, but that's not why we do it.
Sail_______/
Velocity___}
Force_____}
Sun_______*
In this example, the force on the sail from the solar wind continually increases the velocity of the ship, slowly increasing its orbital radius.
Sail_______\
Velocity____}
Force______{
Sun_______*
In this case, the force on the sail is working against the vector of the ship - its velocity, and therefore its orbital radius, will be continually decreasing.
Have you been touched by his noodly appendage?
Here's a tip for NASA: use lasers to launch a ship with a lightsail in the direction of the Coalsack, giving it added thrust. We've simply got to beat those Moaties to it!
Extra points if those lasers are mounted on sharks of course...
Actually, the idea was first proposed by Johannes Kepler in the 17th century. And there are still a lot of basic misconceptions about solar sails and light sails, no doubt because of the word "sail".
Simply put, they don't derive their thrust from the solar wind, the stream of charged particles emitted by the sun, but from the radiation pressure of sunlight (as stated in the summary), which provides vastly greater thrust than the solar wind. They don't tack, or "run before the wind", or perform maneuvers that wind-powered vessels do, they change from one orbit to another (solar or planetary) by using light pressure for minute accelerations or decelerations, doing so by changing the attitude of the main sail with smaller vanes.
"They are well known to science fiction readers, otherwise not so much."
They are well known to those familiar with space history. We learned how to build these sails from Echo 1A and Echo 2, launched back in the 60s. Both were aluminized mylar balloons, used as passive microwave reflecting communications satellites. Both were "blown" off orbit by solar pressure. Analysis of the orbital data told us the why and the how much, so now we can do it accurately.
As for "a previous attempt blew up", the same thing happened to Echo 1. Echo 1A was a backup. Luckily the design was dirt cheap, making that possible. Sadly, then as now, the failures were in the expensive parts -- the boosters.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
Make a Donation Specify Project: Solar Sailing
What's worse is they could read slashdot and believe that they work by photon pressure rather than solar winds. What next? Does reentry burn you up because of friction (rather than rapid pressure change)?
It is no longer uncommon to be uncommon.
They must be doing something right, cause apparently, the rocket is on the pad right now going through dress rehearsals.
clickenzie here.
If Mr. Edison had thought smarter he wouldn't sweat as much. --Nikola Tesla
China did it: http://www.strangehorizons.com/2006/20060102/surfing-hell-a.shtml
I am speaking here as an experienced sailor, you can only sail a direction other than directly with the wind be exploiting the directional stability of the boat. While most of the directional stability of modern sailboat comes from the keel, there is a great degree of resistance to lateral movement caused by hull shape, and that affords you a fair amount of directional stability, which could be used by racing dingys and other sailboats with removable daggerboards and the like to sail in most directions down wind. However in outer space it is impossible to deflect the solar wind at an angle because you lack the grounding to be able to provide any resistance to that wind. The reason that your hand can generate up and down forces when you hang it out of the car window is because of the resistance your arm provides against the wind. Hold a birds feather in front of a fan, as long as you hold on to it you can make it generate up and down forces by changing the angle, but as soon as you remove the resistance provided by your hand and let the feather go, it will move directly with the airflow regardless of the angle of the feather.
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