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Cosmos Solar Sail Getting Close To Launch
digitalcaffeine writes "The Guardian is reporting that US and Russian scientists are planning to launch a spacecraft that will use solar sails to move about in space. This venture, called Cosmos 1, is backed by the Planetary Society and Cosmos Studios. The spacecraft, finally due for launch in late 2004 or early 2005, will use a converted SS-N-18 submarine launched ballistic missile fired from beneath the Barents Sea to get it into a 800 x 1000 km elliptical orbit. It will then unfurl its 15m sails and start moving about. So, for all the governments that have been working on a similar project, the first solar-sailed spacecraft is going to be from a private venture." An update on the official site notes that "The world's first solar sail craft is nearing completion. All electronic systems are now flight qualified and were delivered to the spacecraft for final assembly and testing" - we previously reported on the Cosmos Project and the efficacy of solar sails.
I hope they were reliable. Somehow I don't think NORAD will care for excuses if an SS-N-18 starts dropping towards Chicago.
nos laetus epulor qui would domito nos
will it be ready in time to get Count Dooku back to Coruscant?
Drill baby drill - on Mars
A private venture has had access to an intercontinental missile??
... most people expect it sail off the edge of the world.
Unknown host pong.
I think its great that former weapons are being used for constructive science. Continues a long tradition. Plus, I bet those missiles are the most reliable chemical launch vehicles around -- the military does not mess around when trying to kill people, and frowns heavily on equipment failure. (as a rule)
And was all that talk (Sagan's wife) about it being visible to the world true? Or was it metaphorical? I can't imagine it being THAT big at this point...
Moo.
That sail makes a nice big, easy to penetrate target (no BBW jokes, please).
The article describes the sail as thinner than a garbage back. Even the tiniest speck of space junk would would easily blow a hole in this. And, if that happens enough times, and especially with bigger pieces of space junk, won't it be filled with thousands of various sized holes?
It doesn't seem like it's being put into orbit high enough to avoid this kind of damage. Obviously they thought of this... are the holes inconsequential?
-- "A chicken is an egg's way of making another egg."
Earlier this month the Japanesesuccessfully deployed two solar sails.
You're thinking of the Bussard Ramjet. Solar sails use the momentum of light as thrust, as opposed to sucking up interstellar gas. This has all been covered before, recently even, in a Slashdot article about the Japanese solar sail project.
I want to delete my account but Slashdot doesn't allow it.
Now that we have solar sails, it's only a matter of time before we need to start worrying about space pirates.
Where's Samus when you need her?
They can be hard to stop its true, except when approaching another star, which is the ultimate goal for the technology. The wind from Star B pushes back, slowing it down. When it achieves proper orbit speed, it furls the sails.
Within the solar system, the idea is you get the solar wind to push hard enough to achieve a certain speed, then you furl the sails and it coasts into the new orbit.
Moo.
Besides, it should see lots of stuff on its way out.
Try not. Do or do not, there is no try.
-- Dr. Spock, stardate 2822-3.
you just build a bigger sail. It's light, and that's the point. HUGE sails are possible in a weightless environment, and a bigger sail harnesses more energy.
Moo.
So why the sub? Extra publicity?
IANASSE (Solar Sail Expert), but 15m sounds a little small. I mean we are talking about pushing a satellite around with *photons*. I guess the amount of energy required to move a spacecraft in orbit is miniscule. I remember reading an article about early space efforts that said something like "the smallest rocket motors are little more than cap-gun ammunition but, they are sufficient to nudge a spacecraft in orbit"
What would this technology be used for in the short-term, though? It seems to me that without an immediate way to utilize this solar sail, there cannot be a profitable business application. It belongs more in the realm of the government at this time, as the government doesn't need to turn a profit.
Haec merda tauri est. Ceterum censeo Carthaginem esse delendam.
1) The 5 year solar sail propelled mission to Pluto - is there a way to decelerate as you reach Pluto? Actually, is it really 5 years constant thrust or does the solar sail's thrust decrease as an inverse square law as you get more distant from the sun?
2) Can you sail "upstream" into the solar wind? Is it possible to tack and jibe in a solar sail propelled craft?!
This is not a sig
Posted before under the Japanese Solar Sail Deployment:
Though Solar Sails are often associated with interstellar travel they have many extremely useful applications in Earth orbit and local solar system exploration. Most potential applications take advantage of the continuous thrust and zero fuel payload of a solar sail.
Near Earth, Solar Sails are particularly suited for high orbital inclination satellite missions. Weather forecasting and global positioning systems would directly benefit from satellites orbiting the poles. Most satellites take advantage of the natural speed of Earth's rotation to boost them into an orbit relatively close to the equatorial plane. Changing the plane requires a large fuel burn for a conventional rocket and greatly increases launch costs. With its small but continuous thrust, a solar sail can reach polar orbits without a massive fuel payload, making them more accessible to scientific research.
Away from Earth, Solar Sails offer a number of other interesting options. Missions have been proposed for asteroid rendezvous, travel to the inner planets (yes, solar sails can travel toward the sun), and an interesting idea using Lagrange points. More advanced solar sails could use their continuous thrust to enlarge the regions where they are able to "hover" well away from Earth. This allows much better observation of solar activity. Solar sails not only have an appealing sci-fi flair, but appear to be quite practical as well. I hope to see the technology develop rapidly.
But I thought the idea of solar sails had been scrapped due to the relaitve scarcity of interstellar hydrogen?
Actually, light alone is sufficient to produce thrust. The problem is that at 1.3kw/m^2 (the power that reaches Earth), you're not going to go very fast with the mass of the solar sails added on.
I've been keeping an eye on Mini-Magnetospheric Plasma Propulsion (M2P2) technology, myself. Basically, it uses an EM field to increase the surface area of the ship without the added weight of solar sails. As a bonus, the ship is protected from the most common forms of radiation and cosmic rays. The concept is particularly interesting when one digs the Orion concept out of memory.
The biggest problems with Orion were plate ablation and scalability concerns (scaling DOWN, not up). With an M2P2 shield, you could use larger pulsed units, and there's no plate to erode. As a bonus, radiation protection comes as a nice side-effect. (Although some steel would still be needed to block neutron radiation.)
Javascript + Nintendo DSi = DSiCade
Within the solar system, the idea is you get the solar wind to push hard enough to achieve a certain speed, then you furl the sails and it coasts into the new orbit.
Umm, no.
What you want to do is find the optimal use of the available thrust, which is to accellerate continously. The first half of the trip is increasing your velocity relative to your target, and the second half is decreasing velocity to match the target. If you have some other means of slowing down at the end, such as aerobraking or a chemical rocket for orbit insertion, you can spend more of the time speeding up.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
come sail away
come sail away
Come sail away with me
Just toss out the space anchor.
This issue is a bit more complicated than you think.
It's much worse than that. Solar sails don't convert the energy of the light, they just receive momentum from the light as it bounces off. The momentum is equal to the energy of the light divided by the speed of light.
This was not a solar powered craft, it was just a test launch using a less than impressive rocket, to test how the sail(s) would unfold in a space environment. A good test, a great project, but not a solar powered craft in any sense of the imagination.
karma capped
well the real world is not full of optimal situations.
Every interplanetary mission to date has been pretty damn close to optimal from an orbital-mechanics standpoint. It's too expensive to go, otherwise.
be happy with creating an orbit with your sail and then furling them up.
You furl them up when you get to your target.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
How does a private company get ahold of a submarine-launched ballistic missle? We could sure use one of these for our current... uh... project. Where can I get one?
Osama Bin Laden
Helpful if we ever have a whale-seeking probe come to our planet and we need to generate some quick power.
Don't forget that God looks like a few stars that light up when he talks.
You really should stop sitting in front of Christmas trees while on acid.
Just attach a bungi chord to the earth on the way out...and snap back home
A solar sail has three forces acting on it. Gravity, pulling it towards the primary (planet or the sun), light, pushing it in the direction it aims the sail, and solar wind, pushing it away from the sun. How much you can balance these to "brake" (say, by tacking against solar orbit and moving back towards the sun) is still a matter of speculation.
But the solar sail is *always* accelerating under these forces. If you get a "gust" you simply reduce sail for a while and adjust trim until you're back on the original course. Unlike a rocket, which has a fixed amount of acceleration and if it needs to change its course it can end up lost in space with no fuel, so long as the sail's intact making corrections is merely a matter of time.
There are no breaks, but you CAN use it to manuver in any direction that is not 'up wind'.
No.
http://www.ugcs.caltech.edu/~diedrich/solarsails/
Solar sails can tack, because slowing your orbital velocity moves you closer to the Sun. If you put the sail at an angle such that majority of the light pressure opposes your direction of motion, you will move inward.
So to slow down, you just alter the angle of the sail. Easy enough.
How's that going to work with Orion? I can't imagine an M2P2 setup withstanding the force of a nuclear blast. Seems to me you've got to be pretty close to the propulsion unit to capture any decent fraction of its energy. It'd be like subjecting a soap bubble to a firecracker.
1. You have to calculate the effective range. i.e. The pulse units must be exploded far enough back so that the pulse doesn't damage the craft.
2. Orions aren't actually propelled by the explosion. The pulse units are sort of "shaped nuclear charges" where all the force is applied to a plate of propellant (tungsten, IIRC). The vaporized propellent collides with the pusher plate, resulting in thrust. The actual nuclear explosion itself would be far enough back not to impart much force on the craft.
In an M2P2 Orion design, you simply choose a propellant that interacts positively with the shield, and adjust the charge to spread it evenly across the surface of said shield.
Javascript + Nintendo DSi = DSiCade
My first thought was the same.
My second thought said 'no'. This had something to do with the way the sails work.
The wind blows against the sail and behind the sail a lower air-pressure (wing effect) pulls the boat forward. But there is also a pushing effect against the sail... So this was BS.
But why does a sailboat sail into the wind? Resistance of the water. It's the shape of the boat, combined with the rudder combined with the resistance of the water that resolves in a forward force. This only works is the bost has enough speed or else it will drift away with the wind.
Well, probably this isn't the whole story, but since the 'water' element lacks in space there is nothing to give the needed friction to sail against the solarwind.
Or at least that's what I think.
Privacy is terrorism.
Dubya's "plan" is about as efficient as waiting for warp engines to be developed before going to Mars.
There are better faster cheaper safer solutions than building Battlestar Galactica in orbit. Unfortunately, defense contractors don't get gigabucks for fielding practical solutions...they get gigabucks for fielding solutions that have subcontractors in every single congresscritter's district.
Hell of a way to run a railroad.
Why yes, I AM a rocket scientist!
...on the feasibility of solar sails can be found in one of Robert A. Heinlein's collections: "Expanded Universe."
Solar sails delivering a 0.001G acceleration are feasible - and yes, you *want* constant acceleration, not kick and coast. At that lousy 1/1000G you get a round trip to Pluto in about 3.5 years. Of course that puts the asteroid belt much, much closer...
3 1/2 years is the same time scale wind-powered ships were on in the 1600-1800's. It made the whole Earth accessible then. The solar sails can make the whole Solar system accessible. Moreover, those sails could be modified in place to - oh, let's say - boil off a bit of front end of a convenient asteroid, for convenient insertion into high-Earth orbit for refining and manafacturing.
And it's a damn good way to use up those old boosters! Recycling rules!
Best,
Mal the Elder
These launchers do fail occasionally, just like any other launcher in the business. In fact, this specific type of launcher has failed on the previous attempt to launch a solar sail by the same group!
...it did fail us on July 20 when the 3rd stage motors failed to provide the necessary velocity change and the rocket computer shut overrode the command to separate the spacecraft from the booster...
Yes, it will most likely be visible. You can see satellites every evening. The sail is bigger than the solar panels of most satellites.
Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.
Snopes
Link
Wikipedia
We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower