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Solar Sail Craft Damaged
C. Mattix writes "It looks like we won't know if the solar sail will work for a while. There was an accident prior to launch that will delay it for quite some time. Full story from Yahoo."
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the greys have damaged the craft because they heard we were getting together a ship for the 2005 galactic cup.
sheesh! once again the slashbots dive right in without being familiar with sailing tradition.
more likely it was a software problem.. a little too much code reuse between the testing and deployment packages
It's too big a coincidence that an accident like this would happen right when America was trying to launch its next generation of space craft. There are no coincidences in this world. It must have been Russian sabbotage.
The Russian space agency must be reeling, now that MIR is out of the sky. They were once a proud nation with a proud space heritage, but now they're a third-world grounded nation begging for international aid from the west. That has to hurt.
So what do they do? They sabbotage America's glorious space program. They're jealous of our potential and they're jealous of our success. They never forgot that we were the first nation in history to successfully fake a moon landing, and they won't forgive us NASA's recent successes with missions to Mars. Worse than that, we insulted their collective genitalia with Taco Bell's publicity stunt which put a target in the Pacific ocean for MIR to land on.
NASA is far too clever to have caused this accident by their own incompetence. America is too strong a nation to let such accidents get in the way of our manifest destiny. We must find the spy who committed this act of terrorist espionage and bring him to justice.
The Cold War is very much alive.
conwstruction of a mirror that effectibely focuses this energy into
the space required is another matter addressed elsewhere . . .
>P>
hawk
hawk, sticking to what he knows . . .
> the square of the distance is it not?
No, it is not.
That is the density for a point source that is radiating in three dimensions. For a lossless focused mirror, the density would be the density at the point of the reflector times the ratio of the area of the reflector to the area of the target. This has to be adjusted for losses at the mirror (less than full reflectivity) and through the air (you hit molecules and disperse, and what's left will be ionizing the air near the target).
hawk, actually a physicicst among his many hats.
that the pyrotechnic circuits work.
From what I recall, it wasn't a micrometeorite that did the tether in.
They were doing experiments with electricity generation with tethers, and they found that much more electricity was generated than expected. The tether broke, and when they landed they insepected the severed end. It had been burned through by an electric arc, which gives you a good demostration of generating electricity by moving a wire at speed through the earth's magnetic field.
If tits were wings it'd be flying around.
You don't need to expend fuel to change the orbit. Put some solar cells on your spacecraft, and you can send a current down the wire to act against the magnetic field. How about that? You've used solar power to maintain your orbit. This is a neat tether trick which would be very useful.
If tits were wings it'd be flying around.
I'm glad it hasn't been launched, solar sails are far too dangerous to be allowed in orbit.
Before you condem me, think of the facts. They are talking about orbiting a huge, acre sized, piece of mylar, with controls to change it's orientation.
It's a giant space mirror!
For those of you didn't read the Mars trilogy, think back to the first time you played with a magnifying glass in your backyard.
Because far too many people seem to be taking this (hopefully) humorous post seriously:
While you could fry things magnifying-glass style with a concave mirror, you won't be able to with a solar sail. To focus light properly at all, the mirror would have to have a very precisely controlled shape. You *could* put a complicated and heavy support structure around a space mirror to adaptively shape and focus it, but you sure as heck won't see this on any solar sailcraft.
Sailcraft don't need to focus light; they just need to reflect or scatter it more-or-less backwards (or at least, less forwards than it was when it came in). Thus, they don't bother with heavy focusing gear, and so wouldn't be able to burn holes in anything if they tried.
Well, I can't speak for anyone else, but I'm paying attention to this project because it's interesting.
If I ignored everything connected to anyone who might have some weird ideas, I'd have to stop reading Slashdot. Hell, I'd have to stop reading, period.
I have a 3 foot fresnel lens that can melt *granite* on a sunny day.
And what is the distance of the focal point? The energy density at the focal point is inversely proportional to the square of the distance is it not? Will the huge sail even have a distinquishable focal point?
Aah, change is good. -- Rafiki
Yeah, but it ain't easy. -- Simba
The solar foils added to ISS/Alpha recently were half an acre in size. This means that if aligned nicely, you can see ISS/Alpha with your unaided eyes. Oooh, the danger. I'm afraid.
If you can focus all of the solar light that hits an earth-acre space, into a much smaller space (say, a 3' square) on the ground, yes, it's gonna be hot and perhaps dangerously hot. But not weapons-grade dangerously hot.
You've been reading too many scifi novellas.
[
From the article I got this vision of someone pushing the "go button" and then having the entire sail unravel inside of a small lab filled with engineers.
...... Oh. Hi. No problem. Just testing. We'll get this fixed. Everyone grab a corner."
"AAaAGGHHH! Not that button!" - As they're all tangled in foil and squashed against the ceiling. - "Real cool Yuri. Now help me get this folded back up before they come
Jon Sullivan
Jon Sullivan
www.jonsullivan.com
Keep in mind, this is not a NASA project. This is a privately funded experiment. NASA has no interest in really pursuing new propulsion techniques. That's why the ISS hasn't been (or isn't even planned to) outfitted with a MEDS style electrodynamic tether for orbital maintenance. An EDT would reduce (if not remove) the dependance on costly space shuttle and Progress space freighter flights to boost its orbit against atmospheric drag.
An interesting note, this solar sail is to be launched atop a former ICBM from a submarine. That, my friend, is the essence of cool.
But some of the prototypes that are overhyped, the makers of the item find a fatal flaw just before the maden use of the item and 'accidentally' damage it, delaying the use of it. Then they get the time to fix it with the update or patch that it requires.
Saves them from the embarassment of launching something that will not work. On the other hand it does end up with a correct item that works as expected so everyone is happy.
Again, just something to think about.
DanH
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Perhaps the peak of the solar cycle will have passed by then. IANAA (A=Astronomer), but I gotta wonder what a Coronal Mass Ejection would do to a thin sheet of mylar. Imagine not being able to AIM SolarSail1...
If you love God, burn a church!
Ewige Blumenkraft!
I'm glad it hasn't been launched, solar sails are far too dangerous to be allowed in orbit.
Before you condem me, think of the facts. They are talking about orbiting a huge, acre sized, piece of mylar, with controls to change it's orientation.
It's a giant space mirror!
For those of you didn't read the Mars trilogy, think back to the first time you played with a magnifying glass in your backyard.
Now, scale that up to a beam of light, a yard wide and more intense than a steel melting laser beam. Think what the beam of light could do to any cities or countries that don't kow-tow to the US-Russian space hegemony.
Worried yet?
Thus proving what we developers already know: QA is the cause of all our problems.
Dancin Santa
The sun isn't a point source. It's about half a degree across, as seen from here.
Its image will be about half a degree across, as seen from the mirror.
If the mirror is 100 km up, that means the image of the sun will be around 1 km across.
It won't be very hot, unless the sail is much bigger than that.