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Launch Date for First Solar Sail due Monday
PGillingwater writes "The Planetary Society (home of SETI) is planning to launch the first Solar Sail Spacecraft, Cosmos 1, later this month. The exact launch date is scheduled to be announced on Monday, May 9. This event represents one of the first privately-funded space missions with the objective of pure research. It will be launched from a Russian submarine in the Barents Sea. The spacecraft consists of a body surrounded by 8 triangular sails, that will use the tiny force of reflected sunlight to (potentially) accelerate to tremendous speeds. Unfortunately, the craft is not expected to leave Earth's orbit due to degradation of the mylar materials, but should be a proof of concept for subsequent missions."
To combat this, and see how it performed out of orbit, could it not have been launched from orbit? In any case, this is pretty interesting...I'm keen to see the results.
In the end, this kind of research will be vital to the survival of the race.
Why all this concern with "survival of the race"? You have to face the inevitable fact that all things come to an end, even entire species, even if they are dispersed across the galaxy. We will invariably go extinct sooner or later, one way or another.
Serious impacts are a low enough probability event not to worry about at this point; if our planet becomes uninhabitable for humans, it will be self-inflicted and there are far simpler ways of preventing that than space flight.
In any case,solar sailing is a great thing, not to ship a few carcasses to another planet, but because it lets us do great science.
Well, the max speed is 99.99% of the speed that particles are being ejected, or, in terms of solar sails, 99.99% of the speed of the solar wind that pushes the craft along. This is jolly and dandy, until you take into account that accelleration virtually stops once you hit heliopause.
I RTFA'd, and didn't see the answer to this question: why launch from a submarine? Presumably all these old submarine-launched missiles would be less trouble to launch from land. What's the advantage of doing it at sea?
In fact, there is just about no conceivable way for our planet to become less inhabitable to humans than any alternative in our solar system. Even after an impact the size of the one that killed off the dinosaurs, you'd be much better off in a bunker on earth than trying to survive in a tin can on dry, oxygenless Mars.
If we are concerned about the survival of the species in face of these kinds of events, we should build a few Dr. Strangelove-style shelters deep underground. It would be easily doable with current technology, and it would be far cheaper than trying to establish colonies on lifeless planets.
Acceleration = (2*Intensity*Area of the sails)/(speed of light * mass) The intensity of sunlight at earth's orbit is 1400.0 Wm^-2 If anyone can find the weight and size of the sails it should give you a pretty good estimate on how fast this thing is gonna go (ignoring effects due to orbital motion).
Resources in space might be necessary to meet the challenges we face over the next century or two. The resources available in just the Near Earth Asteroids are, if you'll pardon the pun, astronomical. A typical large type M asteroid might have as much as a 150 billion dollars worth of platinum and enough iron to replace all the mining done on Earth for five years. With the resources in the asteroids, we could build enormous structures in space without having to lift mass off the Earth. If fusion is ever to be a real power source, it's likely that we'll need the helium-three that is available in large quantities on the Moon, and almost non-existent on Earth.
Moving power production and dirty industries to space might be a way to continue to improve the standard of lving for humanity as a whole, without destroying our environment.
The threat of a catastophe that is purely natural is also real, even if the probability is low. Asteroid 2004 MN4 seems likely to come very close, if not actually hit, Earth in 2035 and 2036, depending on how it's course is affected by it's close pass in 2029. Though it's not a dinosaur killer, it's big enough to do serious damage. Many of the readers of slashdot will be alive when that happens. There is also a tiny, but real chance that a super-caldera, such as the one in yellowstone might erupt, which would be devistating for the entire planet. It's risky to have all our eggs in one basket.
You shouldn't discount what might be learned by moving into space. Being forced to create and maintain balanced ecologies will give us great insights into how the Earth works and how to better manage it.
The Earth is not naturally hospitable to human beings. There are plenty if records of dramatic changes that have taken place that would have wiped out human beings like they did most other species.
The knowledge we gain from science is itself worth the investment, but that doesn't mean we shouldn't constantly be looking for ways to use what we learn to deal with our current and future needs.
-All that is gold does not glitter - Tolkien
www.ra
They tested a solar sail by launching it.
No, they tested a solar sail deployment system. Read the OP's link or at least my quote from it, why don't you?
Not that I don't agree that it is a bit of a stretch to call Cosmos 1 a spacecraft, but it is surely more of a spacecraft than the Japanese deployment system, which is why I specifically said that Cosmos 1 might still get to be the first (solar sail-powered spacecraft).
"Total destruction the only solution" - Bob Marley
For anyone curious, the price is about $4 million which relatively speaking, is low cost.
:-) Although no doubt the one they're using is different and $pace-rated.
I had a brief grin when it occurred to me that I could afford to buy this inter-stellar propulsion component myself at Wal-Mart.
Interestingly, from TFA, this is a solar sail as opposed to a light sail, so presumably it's better at catching the momentum of the particles in the solar wind than the actual light from the sun. It's worth noting that for pure solar wind sailing (without light sailing) the sail doesn't even need to be reflective to light.
Beyond the heliopause there is no solar wind by definition (and precious little solar light pressure too), so light sails need to be pushed by massive ground-based lasers which would typically be installed on the moon. I wonder if the same aluminized Mylar sail would still work, or would a craft need to deploy a different kind once it gets that far out?
Yeah .. I was gnashing my teeth a little when I read they were making it from mylar (polyethylene terephthalate). Not only will it degrade quickly, but it is also heavier, weaker, and less resilient than other available materials (16% denser than polycarbonate, 33% denser than polyurethane, either of which would have been stronger + more resilient).
I'm guessing, though, that they went with an off-the-shelf solution for the material to lower costs and expedite production. DuPont already mass manufactures aluminized mylar at this thickness, and I don't know if anyone manufactures similarly thin polycarbonate films, aluminized or not. Optically clear polyurethane is probably too new for anyone to be manufacturing it in film.
-- TTK
Because there really is a competition in the launch industry. And the ISS, sold to Americans as a way to mutually advance the tech. But, as I pointed out, the USA got stuck with the nearly-useless showpiece, dragged down by dependence on a Russian division that routinely misses deliveries and needs budget injections. Which cuts into the limited US space resources, resulting in less US R&D. While Russia turns around and races ahead in more promising R&D, like these lightsails. Which experience they don't really share with the USA - they can report results, but proficiency is an actual experience in person, by real teams.
So I don't regard foreign missions as failures - nor did I ever say so (nice strawman fallacy). I do regard subsidizing a Russian mission which strategically hands us an anvil, rather than the baton, in our relay to space proficiency, as a failure of US policy, and the partnership. And I regard foreigners portraying that actual situation as some kind of American arrogance, when it is exactly the opposite, as a selfserving con game consistent with the rest of the ISS boondoggle.
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make install -not war