Well, the problem with cheap probes is that NASA doesn't want cheap. NASA wants a mission to be expensive, as high as they can get "without going over" to the point where Congress will cancel it.
NASA's purpose is to hire and pay themselves and their contractors. Actually exploring space is a distant second priority. This has been true pretty much since the first Shuttle started development.
Somebody besides NASA could certainly do cheap space probes, but it won't be American.
The point of the space elevator isn't to get into orbit without expending energy. The point of the space elevator is to get into orbit without the tremendous inefficiency of rockets.
Rockets are so tremendously inefficient because they need to lift all their fuel with themselves. Something like 20% of the space shuttle's fuel is needed just to lift the other 80% of the fuel above the 500-foot altitude of the launching tower. Then you have to spend a good chunk of the remaining fuel just to raise the rest of the fuel up another 500 feet, and so on. It's geometrically inefficient.
With an elevator, as you describe, energy has to be applied both to raise the load's altitude and to get it up to orbital speed. This isn't a trivial problem, but it's solvable with far less overall energy expenditure than rocket fuel. In principle, electric motors can do the lifting work. It's far easier to lift electricity slong a wire to orbital altitudes than to lift rocket reaction mass.
I'm fairly clumsy, and in my computing career, I've spilled drinks on a half-dozen keyboards and at least two motherboards. But all of them worked just fine after drying out.
The secret? Drink only water. I can do my computing without dependency on mind-altering drugs like caffeine and alcohol. And why pay for soda when water's free and doesn't expand your waistline or rot your teeth?
The analogy holds. Your sailboat could take photos of Hawaii, but you wouldn't see much. You'd only see the front edge of an island, with a beach and one layer of trees or buildings. Compare this to an aerial view that would show everything.
So it is with Saturn; you need to be outside the rings looking at the entire expanse to really see them. From within the rings, you really wouldn't see much.
In a nutshell, here's how Cassini will interact with the rings during the orbital insertion.
Saturn right now is tilted, so that the south/"bottom" side of its rings is facing towards the Sun and Earth. Hence, Cassini is approaching Saturn from "underneath" as we see it from Earth. The orbit insertion requires Cassini to pass through the equatorial/ring plane south-to-north as it approaches the planet. It will fire its rocket while on the north side of the rings, and then coast back to the south side on its way back out.
Now, how is Cassini doing that safely? It's doing so by going through the ring plane where there are no rings. It could be thought of as a "gap", but Cassini really isn't anywhere near the rings when it crosses them. The crossing points are far outside the main mass of the ring system.
A rough analogy is this. Suppose you lived in Alaska, and had a sailboat named Cassini. Now suppose you had to sail from Alaska to Mexico without bumping into anything. Naturally, you'd pass between Hawaii and the continental US. That's a rough analogue to what's going on at Saturn - the main mass of the rings is like the continental US landmass (and there's a few small intra-ring gaps like the Mississippi River), while there's a few small outside rings sort of like the Hawaiian islands.
Would it be possible that your sailboat bumped into a rock or debris or something that we didn't know was there? Yes. Is that possibility remote enough that it makes for the safest course to your destination? Also yes.
Microsoft should release a service pack to Windows that sets the security settings on MSIE to their highest levels, even at the risk of breaking many web sites.
In fact, this has already happened. Have you ever used a default install of IE on a Windows 2003 machine? Everything's set for really high security. You can't even *download* an.EXE file by default. You have to manually add the site to the Trusted Sites list, and you're pretty much expected to do that with any site you want to do anything more sophisticated than reading a static page.
Supposedly, this configuration will be rolled into XP Service Pack 2 as well. No word on what Windows 2000 users get.
Of course, the spyware vendors will just add instructions that say "To play this game, click on Trusted Sites and add www.fuckyourcomputer.com". And the masses will obey.
And of course, Microsoft uses it as yet another marketing opportunity. Every single prompt and dialog involved trumpets "Microsoft's New Enhanced Security Configuration Initiative". As if we should be thankful to them for fixing holes that THEY caused in the first place.
Not that anybody's going to read this topic, but here's the answer. Cassini does take both color and grayscale photos. Just like in any other environment, color requires more data and more processing. The majority of Cassini's photos are grayscale because they're easier and faster to take. There will be some color pictures once the data is processed and released, but there's more grayscale pictures and it's easier to get them out faster. And it's not like Phoebe is a colorful object anyway.
Strictly speaking, the spacecraft doesn't have a color camera. Rather, all of its cameras can be equipped with filters for various wavelengths - red, green, blue, infrared, ultraviolet, and so on. Taking a color picture requires multiple exposures through different filters, so it takes longer and delivers less resolution.
Finally, color pictures really aren't that valuable for science anyway. They make for pretty pictures and posters, but that isn't Cassini's job. Filtering at different wavelengths is important for some objects (particularly Titan and the rings), but for other objects, grayscale images usually convey very close to 100% of the scientific information that a color picture would.
Variation is the theme restated and elaborated in slightly altered and embroidered ways. Variation is the means by which we intensify the user's comprehension and appreciation of our theme, and leverage his/her growing consciousness in new ways.
I don't think I've ever before seen more words used to say less.
The theory that Iapetus was darkened by dust from Phoebe is alluring, but doesn't really hold up to scrutiny. It looks logical when you see a drawing of the Saturn system, with the half-dark moon sitting next to the dark moon, but that's about where the plausibility ends.
First, the moons are far, far apart. Phoebe orbits 5x farther from Saturn as Iapetus does - a difference on the order of 10 million km. Phoebe would have to be emitting a tremendous amount of dust for Iapetus to pick up any remotely visible amount of it.
Second, their orbits are inclined approximately 160 degrees apart. Iapetus orbits almost in Saturn's equatorial plane; Phoebe is nowhere near it. There's no astrophysical reason for the dust to get into Saturn's equatorial plane and stay there waiting for Iapetus. (Saturn's rings remain compressed into the equatorial plane by tidal forces near the planet, but those forces become extremely weak that far out. Iapetus orbits 30x farther from Saturn than the outermost large ring, and tidal forces decrease with at least the square of distance.) The volume of space that would have to be dusted by Phoebe to visibly darken Iapetus is simply prohibitively large.
Third, if Iapetus is darkened by dust, why not any of Saturn's other moons? OK, we don't yet know if Titan is, but the other moons should show some evidence of the same process, and they don't.
Fourth, Iapetus isn't half-and-half black and white like a chessboard or that race in Star Trek. Voyager showed that the dark area is a roughly circular area, roughly centered on the leading orbital hemisphere, with a highly irregular border. And there are light spots within the dark area - not a single dot in the center, but a few separated irregular areas. It's a surface feature of the moon with lower albedo, not "this half is black."
The dark area occupies a proportion of Iapetus's sphere similar to the proportion of the Pacific Ocean compared to Earth's sphere. Discounting the Velikovskyists, we're fairly sure that the Pacific Ocean was formed by Earthbound processes on our planet, so Iapetus's geological history could well have had something of similar scale.
I doubt we'll ever know for sure until an Iapetus lander spacecraft, which isn't even remotely in NASA's future plans yet. Yes, something weird happened on Iapetus, but it wasn't dust from little Phoebe.
Of course you're trolling, but do you know how the whole Pokemon thing actually got started?
Go back a bit further, to the Tamagotchi virtual pets. Companies noticed that girls were buying them in droves, but they weren't selling much at all to boys.
Solution? "Make 'em fight each other." The rest is history.
Pulsejets, turbojets... what's the big deal? They invented Laserjets years ago. Can get one of those for $400 or less, and the laser just runs on electricity, doesn't need fuel...
I'm surprised how fast all the flaws with the video were exposed by readers here. How did Linus's Law go again... "With enough eyeballs, all fakery is shallow"...?
First, let's define "assembly language programming" as "accomplishing something using assembly language".
There are (at least) two components to doing that. First is knowing and using assembly language itself. This is knowing what the machine registers are (AX, DX, SI, DS, etc) and how to manipulate them using assembly instructions (MOV, JMP, etc.) This part is the same for all uses on an x86 platform - Linux or DOS or Windows or your own operating system.
The second part of assembly programming is interfacing with other software routines to do something useful or fun. Unless you're writing your own OS from scratch, this is necessary. Suppose you want to load a file from disk into memory space so you can do something with it. You'll want to interface with existing OS file operations; you don't want to write code to navigate the OS file structure and read from the disk byte-by-byte.
Under DOS, you do this by loading data into certain registers to indicate parameters (references of a filename and of a memory space to load the data into) and executing the assembly instruction INT 21h. DOS code then finds the file on disk, goes through file-locking routines as necessary, and copies its data into the memory space you specified.
Under Windows, this is completely different. You push parameters onto the stack to simulate a C stack calling frame, and then you transfer control with a CALL instruction to a Windows API function in a DLL somewhere. Then the Windows code finds the file and loads it into your memory space. That can involve very complicated things like connect to another machine over a network and pop up a box to the user for a password - you definitely did NOT want to reinvent all that in assembly yourself.
Under Linux, there's yet another convention to accomplish something like that (I'm ashamed to confess that I really don't know how it's done in Linux.)
But that's how "x86 assembler" is the same yet differs drastically on different platforms.
Slashdot Mirror
Well, the problem with cheap probes is that NASA doesn't want cheap. NASA wants a mission to be expensive, as high as they can get "without going over" to the point where Congress will cancel it.
NASA's purpose is to hire and pay themselves and their contractors. Actually exploring space is a distant second priority. This has been true pretty much since the first Shuttle started development.
Somebody besides NASA could certainly do cheap space probes, but it won't be American.
My bet's on KABOOM, but no ash or lava.
So the way to win is to make sure you *don't* imagine a Beowulf cluster of these?
1300 AD:
"I've got splinters of the True Cross! Really! Buy one!"
2300 AD:
"I've got splinters of the crashed Space Elevator! Really! Buy one!"
Rockets are so tremendously inefficient because they need to lift all their fuel with themselves. Something like 20% of the space shuttle's fuel is needed just to lift the other 80% of the fuel above the 500-foot altitude of the launching tower. Then you have to spend a good chunk of the remaining fuel just to raise the rest of the fuel up another 500 feet, and so on. It's geometrically inefficient.
With an elevator, as you describe, energy has to be applied both to raise the load's altitude and to get it up to orbital speed. This isn't a trivial problem, but it's solvable with far less overall energy expenditure than rocket fuel. In principle, electric motors can do the lifting work. It's far easier to lift electricity slong a wire to orbital altitudes than to lift rocket reaction mass.
I'm fairly clumsy, and in my computing career, I've spilled drinks on a half-dozen keyboards and at least two motherboards. But all of them worked just fine after drying out.
The secret? Drink only water. I can do my computing without dependency on mind-altering drugs like caffeine and alcohol. And why pay for soda when water's free and doesn't expand your waistline or rot your teeth?
The analogy holds. Your sailboat could take photos of Hawaii, but you wouldn't see much. You'd only see the front edge of an island, with a beach and one layer of trees or buildings. Compare this to an aerial view that would show everything.
So it is with Saturn; you need to be outside the rings looking at the entire expanse to really see them. From within the rings, you really wouldn't see much.
In a nutshell, here's how Cassini will interact with the rings during the orbital insertion.
Saturn right now is tilted, so that the south/"bottom" side of its rings is facing towards the Sun and Earth. Hence, Cassini is approaching Saturn from "underneath" as we see it from Earth. The orbit insertion requires Cassini to pass through the equatorial/ring plane south-to-north as it approaches the planet. It will fire its rocket while on the north side of the rings, and then coast back to the south side on its way back out.
Now, how is Cassini doing that safely? It's doing so by going through the ring plane where there are no rings. It could be thought of as a "gap", but Cassini really isn't anywhere near the rings when it crosses them. The crossing points are far outside the main mass of the ring system.
A rough analogy is this. Suppose you lived in Alaska, and had a sailboat named Cassini. Now suppose you had to sail from Alaska to Mexico without bumping into anything. Naturally, you'd pass between Hawaii and the continental US. That's a rough analogue to what's going on at Saturn - the main mass of the rings is like the continental US landmass (and there's a few small intra-ring gaps like the Mississippi River), while there's a few small outside rings sort of like the Hawaiian islands.
Would it be possible that your sailboat bumped into a rock or debris or something that we didn't know was there? Yes. Is that possibility remote enough that it makes for the safest course to your destination? Also yes.
In fact, this has already happened. Have you ever used a default install of IE on a Windows 2003 machine? Everything's set for really high security. You can't even *download* an .EXE file by default. You have to manually add the site to the Trusted Sites list, and you're pretty much expected to do that with any site you want to do anything more sophisticated than reading a static page.
Supposedly, this configuration will be rolled into XP Service Pack 2 as well. No word on what Windows 2000 users get.
Of course, the spyware vendors will just add instructions that say "To play this game, click on Trusted Sites and add www.fuckyourcomputer.com". And the masses will obey.
And of course, Microsoft uses it as yet another marketing opportunity. Every single prompt and dialog involved trumpets "Microsoft's New Enhanced Security Configuration Initiative". As if we should be thankful to them for fixing holes that THEY caused in the first place.
Not that anybody's going to read this topic, but here's the answer. Cassini does take both color and grayscale photos. Just like in any other environment, color requires more data and more processing. The majority of Cassini's photos are grayscale because they're easier and faster to take. There will be some color pictures once the data is processed and released, but there's more grayscale pictures and it's easier to get them out faster. And it's not like Phoebe is a colorful object anyway.
Strictly speaking, the spacecraft doesn't have a color camera. Rather, all of its cameras can be equipped with filters for various wavelengths - red, green, blue, infrared, ultraviolet, and so on. Taking a color picture requires multiple exposures through different filters, so it takes longer and delivers less resolution.
Finally, color pictures really aren't that valuable for science anyway. They make for pretty pictures and posters, but that isn't Cassini's job. Filtering at different wavelengths is important for some objects (particularly Titan and the rings), but for other objects, grayscale images usually convey very close to 100% of the scientific information that a color picture would.
Variation is the theme restated and elaborated in slightly altered and embroidered ways. Variation is the means by which we intensify the user's comprehension and appreciation of our theme, and leverage his/her growing consciousness in new ways.
I don't think I've ever before seen more words used to say less.
The theory that Iapetus was darkened by dust from Phoebe is alluring, but doesn't really hold up to scrutiny. It looks logical when you see a drawing of the Saturn system, with the half-dark moon sitting next to the dark moon, but that's about where the plausibility ends.
First, the moons are far, far apart. Phoebe orbits 5x farther from Saturn as Iapetus does - a difference on the order of 10 million km. Phoebe would have to be emitting a tremendous amount of dust for Iapetus to pick up any remotely visible amount of it.
Second, their orbits are inclined approximately 160 degrees apart. Iapetus orbits almost in Saturn's equatorial plane; Phoebe is nowhere near it. There's no astrophysical reason for the dust to get into Saturn's equatorial plane and stay there waiting for Iapetus. (Saturn's rings remain compressed into the equatorial plane by tidal forces near the planet, but those forces become extremely weak that far out. Iapetus orbits 30x farther from Saturn than the outermost large ring, and tidal forces decrease with at least the square of distance.) The volume of space that would have to be dusted by Phoebe to visibly darken Iapetus is simply prohibitively large.
Third, if Iapetus is darkened by dust, why not any of Saturn's other moons? OK, we don't yet know if Titan is, but the other moons should show some evidence of the same process, and they don't.
Fourth, Iapetus isn't half-and-half black and white like a chessboard or that race in Star Trek. Voyager showed that the dark area is a roughly circular area, roughly centered on the leading orbital hemisphere, with a highly irregular border. And there are light spots within the dark area - not a single dot in the center, but a few separated irregular areas. It's a surface feature of the moon with lower albedo, not "this half is black."
The dark area occupies a proportion of Iapetus's sphere similar to the proportion of the Pacific Ocean compared to Earth's sphere. Discounting the Velikovskyists, we're fairly sure that the Pacific Ocean was formed by Earthbound processes on our planet, so Iapetus's geological history could well have had something of similar scale.
I doubt we'll ever know for sure until an Iapetus lander spacecraft, which isn't even remotely in NASA's future plans yet. Yes, something weird happened on Iapetus, but it wasn't dust from little Phoebe.
His use of random spam words caused a thermonuclear fission explosion in your filter?
I guess that would make sure that nothing got past your filter, except maybe some shrapnel...
"Given enough eyes, all obscurity is shallow" ?
Of course you're trolling, but do you know how the whole Pokemon thing actually got started?
Go back a bit further, to the Tamagotchi virtual pets. Companies noticed that girls were buying them in droves, but they weren't selling much at all to boys.
Solution? "Make 'em fight each other." The rest is history.
"Doctor's office, how can I help you?"
"Help! My nervous system keeps rebooti---"
Pulsejets, turbojets... what's the big deal? They invented Laserjets years ago. Can get one of those for $400 or less, and the laser just runs on electricity, doesn't need fuel...
Google is rapidly evolving into one of, if not, the most advanced search engine in the world.
If Google's actually evolving, it would be reproducing itself, with random mutations that through selection over time will enhance its abilities.
Not that I'm putting that past Google's coders at all...
I'm surprised how fast all the flaws with the video were exposed by readers here. How did Linus's Law go again... "With enough eyeballs, all fakery is shallow"...?
These days I carry a P-48 on my keyring
I think your FDIV-bugged Pentium-60 keychain is underclocked.
From the parent's link ( http://promo.net/pg/vol/pd.html ) :
"Works first created on or after January 1, 1978 enter the public domain 70 years after the death of the author if the author is a natural person."
I guess this rule doesn't apply for works created by a cloned person?
First, let's define "assembly language programming" as "accomplishing something using assembly language".
There are (at least) two components to doing that. First is knowing and using assembly language itself. This is knowing what the machine registers are (AX, DX, SI, DS, etc) and how to manipulate them using assembly instructions (MOV, JMP, etc.) This part is the same for all uses on an x86 platform - Linux or DOS or Windows or your own operating system.
The second part of assembly programming is interfacing with other software routines to do something useful or fun. Unless you're writing your own OS from scratch, this is necessary. Suppose you want to load a file from disk into memory space so you can do something with it. You'll want to interface with existing OS file operations; you don't want to write code to navigate the OS file structure and read from the disk byte-by-byte.
Under DOS, you do this by loading data into certain registers to indicate parameters (references of a filename and of a memory space to load the data into) and executing the assembly instruction INT 21h. DOS code then finds the file on disk, goes through file-locking routines as necessary, and copies its data into the memory space you specified.
Under Windows, this is completely different. You push parameters onto the stack to simulate a C stack calling frame, and then you transfer control with a CALL instruction to a Windows API function in a DLL somewhere. Then the Windows code finds the file and loads it into your memory space. That can involve very complicated things like connect to another machine over a network and pop up a box to the user for a password - you definitely did NOT want to reinvent all that in assembly yourself.
Under Linux, there's yet another convention to accomplish something like that (I'm ashamed to confess that I really don't know how it's done in Linux.)
But that's how "x86 assembler" is the same yet differs drastically on different platforms.