Japanese successfully deploy space solar sail
Scientists with the Japan Aerospace Exploration Agency, aka JAXA, have successfully deployed a space solar sail on the IKAROS spacecraft, the first demonstration of a space propulsion technology with potentially far-ranging applications.
A solar sail is a thin membrane that harnesses the pressure from photons striking its surface to push a spacecraft through space. There is no fuel to use up, so it holds great promise for uber-long-distance space travel.
In addition to photon propulsion, the sail also has thin-film solar cells, making it a hybrid power source.
Here’s a description of the sail’s deployment: “The membrane is deployed, and kept flat, by its spinning motion. Four masses are attached to the four tips of the membrane in order to facilitate deployment. Deployment is in two stages. During the first stage, the membrane is deployed statically, and during the second stage, dynamically. This deployment method can be realized with simpler and lighter mechanisms than conventional mast or boom types as it does not require rigid structural elements.”
Previous attempts to launch and deploy a solar sail, such as the attempt by the Carl Sagan-founded Planetary Society in 2005, failed due to launch problems. The Planetary Society is planning on another attempt by the end of the year, LightSail-1.
[Via BBC, Wired.]
Andy T commented:
Good news everyone: satellite.tmcnet.com/topics/satellite/articles/137502-nasa-nanosail-d-spontaneously-back-business.htm
Andy T commented:
Looks like NASA is now building a sailed spacecraft, to launch this fall. The 100 square foot sail is rumored to be made $100 bills.
www.nasa.gov/mission_pages/smallsats/10-109.html
Andy T commented:
No, i haven't forgotten my laws of motion. If it's to go anywhere useful, it needs to continue accelerating. Close to the speed of light as an objective speed might be a good start for any alternative propulsion scheme, especially one pushed by photons; at least until I get the kinks out of the warp drive I almost have working in my basement. Do you guys even realize what the lead time on dilithium crystals is these days?
J. Williams commented:
Yes, but can you tack into the sun?
digengr commented:
1. Once moving, it stays moving so distance it ends up from the sun isn't an issue. Unless you are counting on it's continued acceleration.
2. Almost all of the "junk" is in a small band starting at 1200 miles alt., so there is a lot of "space" in space, I think that where it got its name. Think about it, surface is a "r" squared function, so you add 1200 to the radius of the earth and square that... big area to find something that can be as small as a jack-in-the-box and never gets larger than a school bus.
William Ketel commented:
I certainly hope that there do not wind up being any unintended consequences in the future from doing something like this. Yes, the solar flux from our sun will drop off, but there are a whole lot of other suns out there, and some of them are much brighter than ours. What happens if this thing collects debris and winds up like a commet, and weighs hundreds of tons when it returns in a hundred years? Am I the only one who has thought about that? A spinning mass of any size could be the start of something big.
Yes, I am aware that this is a bit of a stretch, but still within ther ealm of possibility.
Just Me commented:
What one Andy T seems to have forgotten is one of the laws of motion.
AKA. An object in motion stays in motion, unless acted on by an outside source.
So they use the sun and the solar wind to get the critter moving at a substantial part of the speed of light, then pull in that sail and cruse on off into the universe.
Its a cheap way to power a fast long distance probe.
Sure they have to be light weight.
Still lots of science can be done on the cheap.
Sure they may loose one to a meteorite but their cheap and they could deploy a bunch of them on one rocket.
Wood Yafekoff commented:
Yeah that, and I wonder how are they're gona avoid pesky space debris. A passing meteor shower would shred the thin sails to bits.
Andy T commented:
One thing these warp-speed-aspiring radiometer boffins are seeming to forget - photon flux density decreases as the square of distance as the sun more approximately becomes a far field point source of photons.
