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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.
Earlier this month the Japanesesuccessfully deployed two solar sails.
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.
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?
Pretty much. The material is so thin, holes made by space debris won't be larger than the debris itself, and most of the stuff up there is sandgrain size or smaller. Given the size of the sail, a bajillion pinholes won't reduce the effective area much.
"They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
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.
Tacking into the wind requires a keel, and there's no corollary with a solar sail. You can use the sail to slow down, though, decreasing your orbital energy and bringing you towards the sun.
Why yes, I AM a rocket scientist!
For the sub launch, another poster helpfully posted the following information:
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.
It would appear that the scientists want to insert the satellite into a polar orbit, which is confirmed by the fact that the launch point will be the Barents Sea, part of the Arctic Ocean. Since this location is a rather inhospitable region for a conventional launch, the scientists have rather ingeniously selected a submarine launch. The Russian military is highly likely to be the provider making this available for a "reasonable" price, since the mission is scientific in nature. Thus it poses no threat to them, while providing profit where it is much needed.
The reason for using a ballistic missle is that Russia is brimming with extra ballistic missles. They've been decommisioning hundreds, if not thousands of former nuclear missles over the last couple decades. This does not mean they've destroyed the entire missle, merely that the nuclear warheads have been removed, and they're no longer housed in silos or subs for launch against other countries. Since the rockets were designed to carry nuclear payloads, they are both powerful and highly reliable. This obviously makes them an ideal platform for carrying anything into orbit which they can be fitted to carry.
This situation is really a win-win propostion. The scientists get a powerful, highly reliable launch platform and rocket in an inhospitable launch location for likely a rather sweet price. The Russian military gets rid of a decommisoned rocket they just had laying around anyway, and gets to run one of their subs through a launch test complete with the actual launching of a rocket, plus they make a profit on the deal.
// harborpirate
// Slashbots off the starboard bow!
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.