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Solar Sail Fails Again
LtFiend writes: "It seems that they've failed at sending up the solar sail prototype again. This time the unit crashed to earth after the final separation of the rocket didn't execute. What a shame. I really hope this project can get back on track quickly."
Don Negro
Don Negro
Perl 6 will give you the big knob. -- Larry Wall
The idea of using geosynchronous satellites has been around at least since Clarke back around WWII, but if there had never been the government funded Soviet and U.S. space programs, do you really think that the companies who make money uplinking to and downlinking from those satellites would have financed and developed a way to get them into orbit all by themselves as quickly as it happened with all that previous government funded work to piggyback on?
Institutions whose function is to earn a return on investment will usually spend a lot more on applied science research than "pure" science research.
I see even classic Slashdot is now pretty much unusable on dial up anymore.
The solar sail did not fail, the system for getting it to orbit did. The title should read "Conventional Rocketry Fails Again".
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But then again, I could be wrong.
Forgetting the numbers dead for a moment, lets say 8 nukes get through - that's eight cities gone (possibly less depending on how many were trying for a single target). I'll avoid the argument that some small terrorist group would send up just a few nukes as I agree with others that would be pretty stupid for anyone to try.
But take the other side of that argument, what if the ABM stopped the single nuke that was targeting some out of the way place (like somewhere in Montana or Wyoming). Would you say it's a waste of time to try and protect at least some people? Perhaps you just want to be offed in the first round of an exchange, but there might be a few people who would actually want to live. Rather cold of you just to kill them all with numbers. Would you really rather kill everyone in the US than leave 5000 people alive?
One last side argument - from space research, we get unrelated spinoff technologies that help us in our everyday lives (like frozen ice-cream). Might there not be some side benefits from ABM research as well? Or are you also for shutting down NASA and all space research.
I myself am not sure how effective such a system would be, but in general I'm all for research projects. I don't understand why people feel it to be such a waste of money when it could lead to other interesting results and possbily to a useful missile shield. I agree with the orignal poster that people shouting about ABM test failures look to me like the same sort of people that laughed at the Wright Brothers and held up every failed test as absolute proof of the impossibility to succeed.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
what happens if we need to approach a star that has a higher strength solar wind than the one propelling the craft? It seems to me it wouldn't matter what color, etc., the reverse side was, you'd still get a pressure front pushing you away
That's actually exactly what you WANT if you're trying to approach another star.
These things depend on acceleration, not velocity. That is, they don't move very fast at all at first, but each new photon bumps the speed up a little. By the time this craft is halfway between two stars, it's moving at a respectable clip.
Now, as the craft is closer to the target sunthan it is to the source sun, it might be time to put on the "brakes" as it were. How would you do that with a rocket? Turn around and THRUST back toward home. How do you do it with a sail? Turn around and let the target sun push against you. If the target sun is larger, you just fold the wings in a little bit to regulate the effectiveness of the thrust.
When the craft is slowed to a safe approach speed, fold the wings to reduce their effectiveness. Let the sun's gravity pull the craft in more, and regulate the speed with the wings so you don't just get sucked all the way in.
Now it's time to start taking pictures or finding something to orbit safely.
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... and saw the blueprints back in the 80s. These things can be built small. I'd like to say I could tell you more but then I'd have to kill you, but the fact is, I'm gettin' old and I've just plain forgotten most of it...
The invisible hand of the Alpha Centaurians is trying to tell you something!
rights are only "taken away" from people who do not know how to demand them (and I don't use "demand" in a "protester in front of the capital building with a sign" sorta way, but rather knowing how to respond when some terrorist burreacrat shows up making demands of you). "the feds" are like the wizard of oz - big and scarry until toto draws back the curtain.
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Learn the rules so you know how to break them properly.
www.teslabox.com
If you "bend and stretch [the rules] to your will", you are certainly breaking the intent of the rule. So in canada, you're breaking the legislature's intent to steal 30% or 40% or 80% (whatever the rate may be) of your "income", but having learned the rules, you've "done it properly."
The Dalai Lama's Instructions for Life
- Respect for self.
- Respect for others.
- Responsibility for all of your actions.
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Learn the rules so you know how to break them properly.
www.teslabox.com
Cost of Solar Sails - $4,000,000;
Cost of clean up mission - $never revealed;
Trusting Russian Space Technology - WTF?
The Planetary Society Page
More info on Solar Sails
Personally I think that magnetic sails are far more promising than mechanical ones.
Recent research shows that a small amount of plasma can extend a magnetic field tremendously.
ONE nuke is enough to wipe the US off the map
... in fact, it's likely that a single nuke powerful enough to wipe out the US would probably be enough to shatter the planet.
... IIRC, it requires 35 kg of fissionables just to get supercritical. The only credible radiological threat that a briefcase could transport is an area denial attack, where you would mix explosives and radioactive material to contaminate an area.
Better be one HELL of a nuke then
and its FAR easier to transport it in a briefcase anyway.
Briefcase nukes are an urban legend on a par with alligators in the sewers of New York. Nukes are HEAVY
Do not meddle in the affairs of sysadmins,
utter rubbish
little info about planetary society :)
"The Planetary Society was founded in 1980 by Carl Sagan, Bruce Murray, and Louis Friedman to encourage the exploration of our solar system and the search for extraterrestrial life.
The Society is a nonprofit, nongovernmental organization, funded by dues and donations from individuals around the world. With more than 100,000 members from over 140 countries, we are the largest space interest group on Earth. Membership is open to all people interested in our mission."
so go to their site and apply for a membership. it costs only 40$ (30$ for students) for us in europe. its even cheaper for north americans. most of the money goes to various space related projects. as a member you will also recieve their magazine planetary report which is really educational and entertaining to read.
-- http://electronicintifada.net --
The project was launched on a converted Russian ICBM. The fact that the rocket failed is SOME good news at least - maybe all those nukes would just fall into the arctic instead of turning North America into the world's second largest (second after Eurasia, of course, in such a scenario) glass bowl. ;P
Derek
So then if photons have energy (obvious), then they have mass.
And it is well demonstrated that reflecting a photon tranfers momentum. Convert electron volts to grams in your equations and it'll all work out :)
Partially true. While it is indeed correct that the "thrust" that a solar sail can take advantage of (photons striking the sail surface) decreases as the vessel moves away from a star (our sun, for instance), one must remember that according to the Laws of Motion, an object that is in motion will remain in motion unless an external force acts on it. This means that even after there is relatively little motive force (photons) to be used to accelerate the craft, it will not decelerate either as it passes through interstellar space. Essentially, there would be no positive or negative acceleration during the cruise phase to another star, but as the craft approached that star, the photons that it emits can be used to slow the craft down -- and final deceleration and orbital entry could be accomplished by nuclear or chemical rockets (or even ion propulsion.)
i am a soviet space shuttle
"We choose to go to the moon. We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win, and the others, too."
It is from an address given at Rice University in Houston (where Mission Control is located) on September 12, 1962. This is also the speech that contains the phrase "We set sail on this new sea because there is new knowledge to be gained, and new rights to be won, and they must be won and used for the progress of all people."
I look up to Kennedy because he was so truly enthusiastic about the space program like no President since has had the guts to be.
i am a soviet space shuttle
First, it helps to bring the concept of the solar sail as a valid idea to the public eye. Solar sails have been something of a mainstay in some science fiction series as a way of getting to other planets and have even shown up in some popular sci-fi series (one episode of Deep Space Nine, for instance, showed an old Bajoran solar sail vessel, albeit with far too little sail area to accelerate as "fast" as more serious concepts would). However, other more conventional systems (by far the chemical rocket, but followed to a lesser extent by nuclear rockets (does anyone recall the NERVA program that might have sent humans to Mars by the 1980s?) and ion propulsion: how many of you knew that the term TIE Fighter from Star Wars stands for "Twin Ion Engine"? Star Wars never stated what gas was used in those systems, but the gas that has been used in the Deep Space 1 mission and in the Artemis commercial spacecraft. Now that the Planetary Society, which is a well-respected organization, has attempted to actually fly a solar sail, the public will become aware of the possibility.
It helps to bring the existence of such organizations into the spotlight as well. The Planetary Society has been active for decades -- it was founded by Carl Sagan -- and there are others, including what is perhaps the best-known of these groups: the National Space Society. Others, far less well known, exist, ranging from fan clubs for shows like Babylon 5 (which I applaud for showing what space exploration will be like in perhaps a few decades once we've gotten the hang of building spacecraft with rotating gravity sections to avoid the problems that long stays in microgravity cause) to other grassroots groups that give more or less anonymously (that is, they don't get press coverage) to serious efforts.
And it also helps to give people like us the idea that we might eventually actually get to go to space ourselves. If someone can spend $20 million for a ride on a Soyuz capsule, and if a non-profit organization can launch a solar sail, then what could happen in fifty years?
This was, like Apollo 13, a "successful failure".
i am a soviet space shuttle
Well, actually, solar sails don't work in just a bee-line method... they travel in orbits around suns, using different angles of photons hitting the sail to keep in orbit.
To move into a farther away orbit, they just tilt the sails more towards the sun. To move closer, they just tilt the sails away and let gravity take over for a bit. A way to travel large distances would be to just remain in a very close orbit with the sun, gaining speed, and then suddenly tilt the sail at the desired angle to propel the craft in the right direction.
After reaching another star, the speed will be very fast, and it can be slowed down by just tilting the sail towards the other star and entering into its orbit, perhaps.
Using lasers to boost it would be wildly inefficient
No, the theoretical maximum would be close to the speed of light, since your propulsion source is traveling at light speed. A laser can actually provide quite a bit of thrust and can be powered by more efficient means than a reaction-based spacecraft. For example, you could set up a solar array on the moon to power the laser. You can then add thrust to the spacecraft without it having to carry fuel. You could use the same solar array to power a mass driver to launch minerals (and perhaps water) out of the moon's gravity well. We need to start prospecting the moon and asteroid belt and quit tearing the earth apart.
Enigma
Enigma
It may have failed as a solar sail, but it did work perfectly as a drogue chute.
He put his boots up on the table and made a face. "The sig," he smirked. "You can waste your life in search of the sig."
Could you "tack" in an orbit around the sun to build up speed, then break away? I'm pretty sure this would work.
Imagine having the sail at an angle to the sun, the craft placed in orbit around the sun, and the solar wind coming out radially. The path of the spacecraft would be perpendicular to the solar wind, so with the sail angled correctly, you'd accelerate in orbit.
Or something.
We take it as a loss and move on to try again. $4 million can be raised again and could be raised many times over for the amount of money spent on many other space related projects.
Something like solar sails, which can have an immediate return when demonstrated as a proof of concept, should have higher priority over things like missions to Mars, which can not only benefit from the solar sails, but which also provide a return much later. Giving it that type of priority, it could be ready in a couple of months.
In 400 years someone will be sitting on Mars sipping wine in a city and not even remember that a solar sail project in 2001 failed.
"Beware of he who would deny you access to information, for in his heart, he dreams himself your master."
Gah, the technology is already there, I worked on and did research for a thermonuclear propulsion project, pellet bed plutonium reactors (using WEAPONS grade plutonium no less) provide a wonderfully high impulse, with hydrogen as the moderator for the core (Bussard Ramjet anyone?). Unfortunately the fightback from the green groups have basically stoppped large scale projects like this in their tracks.......*sob*
This is perfectly alright and all, except what happens if we need to approach a star that has a higher strength solar wind than the one propelling the craft? It seems to me it wouldn't matter what color, etc., the reverse side was, you'd still get a pressure front pushing you away. Thus, wouldn't some stars be impossible to approach with this technology? Kinda like a one way ticket to the moon; you can get there rather elegantly, but you just can't come back using the solar sail. I realize that I'm not an expert, and perhaps someone can clarify.
I did see an article, I'm not sure whether it was a magazine article or on Slashdot (or both), about a similar idea and application being used as a method to get to the moon. In essence, you make a space craft with a mirror on the bottom. Then you construct a really friggin' powerful laser, aim it at the bottom of the spacesraft (the mirror), and off you go. Darwin award, anyone?To hope, though, there is my favorite engineering saying: It works in reality, but will it work in theory? Just my two cents.Way to steal from a Larry Niven short story.. the one about the teachers from another planet who gave people pills to learn skills.
Why don't you suggest that we make our sun go nova instead?
you should find something more esoteric to plagarize in this arena.. I'm just shocked that nobody has commented on this yet.
Brant
Brant
Argle. Bargle.
If the press notices at all, I'm sure we'll get to hear how much money was "wasted" on this failure. I wish people would accept that failures are part of learning. This is true of all aspects of human life. As long as they find and correct, and learn from, the problem, then nothing was wasted.
...sometimes comes down. I hope this project succeeds, and I think it or one like it will ultimately, but aren't they a little worried about their spacecraft hitting the ground? While not densely populated, the Kamchatka Peninsula does have people living there, not to mention lots of wildlife. I thought the launch from the sub was part of making sure when it came down it did so in the ocean.
Although photons do carry the electropmagnetic force, light is made up of randomly polarized photons and therefore cannot provide propulsive force. Also, since photons have no mass, they cannot have momentum, because momentum=mass*velocity^2 Only particles with mass can propel a solar sail.
Hmmm...you might want to explain that to the folks over at the Interplanetary Society before they send up another one of these things, as they seem to have different ideas:
JPL and NASA seem to be under similar delusions.Here's a good site on how these babys are proposed to work.
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I got nothin'.
Can someone explain to me if, how, and why we use different rockets for manned vs. unmanned missions? Why not just use the most reliable types? Is it a cost issue? Are the manned rockets really safer?
Ok... enough of that. Just a little joke to relax the people (including me) who are infuriated with the Sklyarov thing.
How come they don't just give this sail to some guy who's about to visit the ISS and just have him toss if overboard from ISS?
...your laser pen would push itself across your desk.
The propulsive force of light is only a tiny fraction of the energy carried by it. Therefore, using an orbital laser to push the solar sail once it got out of the sun's range would be wildly inefficient.
It would also be extremely difficult to develop the proper targeting mechanism. Do you haver any idea how hard it is to hit a 1 meter cross section from a light year away?
tan^-1(1/(9.46*10^12))= 1.057*10^-13
The laser would have to be accurate to within a ten trillionth of a degree. The earth's own gravitational field bends light more than that. And, since it would take a year for its image to reach us, and another year+ for the laser to reach it, the course would have to be extrapolated 2+ years ahead. That could create major problems.
Repeal the DMCA!
It doesn't need anything to push against. The solar wind pushes it along. And the reason it was shaped like a windmill, is that it should spin a bit if it gets a push from the solar wind.