Re:Remember the Sonic Cruiser?
on
Son of Concorde
·
· Score: 1
Actually, the sonic cruiser was scrapped because whoever thunk it up must have failed aerospace engineering 101. We just went over this in class. Up until mach.7 or so, the relationship of v versus drag is fairly linear. Once you get above that, the drag starts going up exponentially due to compression of the air. Supersonic flight is actually more efficient than high subsonic flight. After Mach 1 the drag actually falls dramatically before increasing again because the compression and shockwaves are forming at a location behind the airplane since they can't propagate faster than the speed of sound. Therefore, a supersonic transport might eventually be economically feasible, but a high subsonic plane will never be.
If you run linux, Kstars is an excellent and free choice. If you don't, there's a web based sky chart available from Sky and Telescope magazine's website.
Last night I saw them from where I am, in spite of my latitude (40 deg N) and proximity to Washington DC (10 mi to the Capitol Building). I didn't even have to go somewhere light pollution free, but it helped that there were no lights in the immediate vicinity (golf course). They were incredible!
IANACSM (I am not a computer science major) but the algorithm seems to be a standard one taught in CS courses. A google search on the "first fit" algorithm (mentioned in the comments of the code) yields many results such as this one:
* size(block) = n + size(header)
Scan free list for first block with nWords >= size(block)
If block not found
Failure (time for garbage collection!)
Else if free block nWords >= size(block) + threshold*
Split into a free block and an in-use block
Free block nWords = Free block nWords - size(block)
In-use block nWords = size(block)
Return pointer to in-use block
Else
Unlink block from free list
Return pointer to block
*Threshold must be at least size(header) + 1 to leave room for header and link
Threshold can be set higher to combat fragmentation
It's be pretty hard to claim as intellectual property something that's common knowledge....
It explains that the system was compromised back in March by a vulnerability that had not yet been patched at the time. The cracker left a behind a trojan to keep getting in, even after the software was patched. Unfortunately, the FSF people didn't realize it had been compromised until recently, so all the backups for the past few months can't be trusted, hence the verification.
Way down in IBM's official response, it dedicates a complete counter claim (#6) to "Breach of GNU General Public License"
76. SCO has taken source code made available by IBM under the GPL, included that code in SCO's Linux products, and distributed significant
portions of those products under the GPL. By so doing, SCO accepted the terms of the GPL (pursuant to GPL 5), both with respect to source code
made available by IBM under the GPL and with respect to SCO's own Linux distributions.
78. SCO has breached the GPL by, among other things, (1) claiming ownership rights over Linux code, including IBM contributions; (2) seeking to collect and collecting license fees with respect to Linux code, including IBM contributions; (3) copying, modifying, sublicensing or distributing Linux, including IBM contributions, on terms other than those set out in the GPL and after its rights under the GPL terminated; and (4) seeking to impose additional restrictions on the recipients of Linux code, including IBM contributions, distributed by SCO.
If this goes all the way through court, there is no way to avoid a judicial test of the GPL.
So many violations to catch SCO on... you'd think IBM read slashdot....
No person can be charged with the same crime twice.
So, is there some sort of law so that a company can't sue both another company and that company's customers at the same time for the same issue? Otherwise, SCO collects money twice for the same grievance, in the unlikely event that they win. (IBM lawsuit = $3 bn, license = $699x "2.5 million servers" = $1.5 bn (assuming single processor))
Hauled out my little 8" equatorial reflector to a dark sky site Friday night and had spectacular resolution of surface features. Southern polar cap was crystal clear as were many other surface features that I can't describe very well without a map of Mars handy. That was only at 120-240x. 2 years ago, at the last opposition, I looked at Mars through a scientific grade 12" refractor, and it was just a featureless orange ball. This year is much better. The closeness aspect isn't really so much of an improvement (from an observational standpoint) as the lack of dust storms. I just hope I get a chance to point the big refractor at it again this time around.....
I was a MSFS person until about 3 weeks ago, and the difference in purpose is tangible. X-plane will output exactly what forces were acting on the plane to a text file. It's also has a very nice interface for outputting to multiple monitors across the newtwork (e.g. for a full scale simulator). Also, it isn't really gameable, because there are no pre-set scenarios or even an instruction manual (the 15 or so html pages on the CD don't really count). It's not sold as a game either. On the front page of the program's website they show how it's being used to simulate a new aircraft that's never flown in real life. It's not sold in stores and comes in a small brown shipping box with a one page copy of the install readme.
While copies of popular blockbusters can be found on the Internet, sometimes days before the movie is released to theaters, computer copies of films are still too large to easily download and are often poor quality copies made using hand-held camcorders.
Music files, by contrast, are smaller and are CD quality, making them easy to share.
Laughed out loud when I read it. As a college student, I'd have to say my personal observations indicate otherwise for the college student population.
(a) Except as provided in paragraph (b) of this section, no person may operate, nor may any operator or pilot in command of an aircraft allow the operation of, any portable electronic device on any of the following U.S.-registered civil aircraft operating under this part.
(b) Paragraph (a) of this section does not apply to -
(1) Portable voice recorders;
(2) Hearing aids;
(3) Heart pacemakers;
(4) Electric shavers; or
(5) Any other portable electronic device that the part 119 certificate holder has determined will not cause interference with the navigation or communication system of the aircraft on which it is to be used.
Pacemakers and hearing aids have an excpeption... although I'm surprised to see that electric razors and voice recorders specifically do as well...
Well, I believe the technical definition is when it begins to undergo nuclear fusion.
Technically, neither the white dwarf or neutron star is a "star," but a stellar remnant (i.e. were once stars, but now are only luminous from electron and neutron degenerecy*, respectively).
There is no spectrum discrimination, the pulsar mentioned in this article emits primarily in the radio.
Actually, for cataloging purposes, I believe planets are planned to be treated the same as stellar companions, due to similar methods of detection.
*Either that or Kelvin-Helmholtz contration, someone correct me if I'm wrong
The powers not delegated to the United States by the Constitution, nor prohibited by it to the states, are reserved to the states respectively, or to the people.
-------------
However, in 1819, the Supreme Court ruled in McCollough vs. Maryland that federal laws supercede state laws. More information can be found here.
The ruling states The States have no power, by taxation or otherwise, to retard, impede, burthen, or in any manner control the operations of the constitutional laws enacted by Congress to carry into effect the powers vested in the national Government.
That's a very good point, but what the article suggests is that in aircraft with fly-by-wire controls (e.g. flight stick goes to computer, computer goes to control surface) you insert in that computer an irrevocable autopilot linked to GPS. Sure, you could shoot it out, but then you're out all controls or have all controls go haywire.
This would work not too well on older aircraft, where the steering it mostly manual, though.
As for approaches to city airports, they could make pilots lives easier by just restricting the airplane to within a certain distance from the runway's glideslope. Presto, landings easier, terrorism harder.
Hmm, are you sure it's that recent? I know they only pardoned Galileo recently, but the church hasn't been teaching geocentric theory for at least a century, if not two.
The Catholic Church has it's own observatory and has been doing genuine scientific work predicated on the earth orbitting the sun for more than 100 years. Also, the pope endorsed the Big Bang theory around 1950 (although there is no dogma, one way or the other on the subject).
If you read the CAA article and download the actual report, you can see it had the following effects:
"-Compass froze or overshot actual magnetic bearing
-VOR and ILS Course Deviation indicator errors with and without error flag
-VOR Navigation to/from reversal
-Instability of indicators"
There are standards. Cellphones and other strong emmitters of EM radiation can't be used on airplanes.
You can't shield the airplane equipment or make it insensitive to EM signals, it's whole point is to receive weak radio signals at high precision. If you shield anything you block signals to cell phones, avionics or both, thus making them useless.
Also, the reason cellphones are so dangerous is that they are close to the detectors on the aircraft. Radiation intensity decreases over distance, thus a huge radar installation 5 km away is less important than a cell phone 10m away.
And the deviations caused are nothing to sneeze at, according to the report, it messes with the CDIs on the ILS indicators. Not good on an instrument approach in zero visibility!
Lastly, what's the big deal about being out of contact with the outside world for a few hours? Why not just relax and enjoy the view?
True of shoulder launched missiles, but I'm not so sure about things like the Aegis SM2's, or fighter launched air-to-air missiles. However, it's safe to say, it's very very unlikely it's a missile.
I'm pretty sure even SM-3 and PAC-3 can't hit targets above 100k feet. Furthermore, even if I am wrong and they could, who has such advanced SAMs other than the US and could deliver them to Texas?
Compared to the main tank, true. But they use thruster rockets right down to the point they drop subsonic, and these thrusters use hypergolic (self igniting) fuels.
Granted, I'm just trying to say the breakup probably wasn't caused by a catastrophic explosion, rather, more likely, something like heat shield failure.
Not at 200,000 feet. Entry interface is at 400,000 feet. Region of maxiumum heating is at 43 miles up, or 227,040 feet. At that point, they're still doing 15,000 miles per hour. They exit ionization blackout 12 minutes before touchdown, still doing 8200 miles per hour. Surviving egress from an aircraft above Mach 1 is dangerous. Above Mach 3, pretty much not surviveable, unless you have some kind of armored escape pod.
Yeah, You're right, I was mistaken... turned out they weren't as far through reentry as I thought. Eternal optimist that I am, I was hoping........
Agreed. I think we need to replace the shuttle system. It's 30 year old technology.
Maybe some good will come of this and convince Congress to budget for that very purpose....
1. No Surface to Air missile can reach above 100k feet.
2. There is almost no fuel on the space shuttle during reentry.
3. Most likely cause of destruction was damage to heat shield.
4. Survival is possible... space shuttle was relatively slow, already mostly throught the atmosphere the crew may have been able to bail out, and they do have parachutes.
5. This does not bode well for manned space exploration
Really? That's funny.... I could have sworn I made some jaws drop at my school's LUG meeting running UT2003 in linux on my Toshiba Satellite notebook....
Flight Simulator 2002, Black and White, Battlefield 1942 all run without any difficulty. Sure, I could have had a somewhat faster desktop than my laptop (1.7 GHz, gf4go) for the same price, but it works adequately for all demands I have placed on it.
Most importantly, there is a nice wireless hookup in my chem lecture, so I can game away instead of falling asleep.:)
Even if this does turn out to be a natural object, it is probable too small to be of any significance. One of these days we'll have to distinguish between a large boulder in space and a moon. Otherwise we might have to start counting particles of space dust.
...to everyone who commented on how faked the movie looks.
Yes, you could do the same with photoshop... Or better, just look at Star Wars. But most asteroids (and most everything within the solar system other than the planets) are nothing more than little dots on a black field. Contrary to popular belief, much of astronomy is not about pretty pictures.
As for the stars not moving, I'm not familiar with the set up of the Kitt Peak telescope, but they most have some sort of sidereal rate drive motors installed. There isn't much astronomy one can do with a streak.
Asteroids zip by the earth fairly often. You can see the closest ones in the Potentially Hazardous Asteroid (PHA) section of the spaceweather.com page.
What is unusual about this one is that it will be 8th magnitude, which will be easily visible in binoculars or a telescope even in a slightly or moderately light-polluted area. Most of the asteroids that zip by are 12th-14th magnitude and therefore only visible in moderate to large aperture telescopes with dark skies.
Slashdot Mirror
Actually, the sonic cruiser was scrapped because whoever thunk it up must have failed aerospace engineering 101. We just went over this in class. Up until mach .7 or so, the relationship of v versus drag is fairly linear. Once you get above that, the drag starts going up exponentially due to compression of the air. Supersonic flight is actually more efficient than high subsonic flight. After Mach 1 the drag actually falls dramatically before increasing again because the compression and shockwaves are forming at a location behind the airplane since they can't propagate faster than the speed of sound. Therefore, a supersonic transport might eventually be economically feasible, but a high subsonic plane will never be.
If you run linux, Kstars is an excellent and free choice. If you don't, there's a web based sky chart available from Sky and Telescope magazine's website.
Last night I saw them from where I am, in spite of my latitude (40 deg N) and proximity to Washington DC (10 mi to the Capitol Building). I didn't even have to go somewhere light pollution free, but it helped that there were no lights in the immediate vicinity (golf course). They were incredible!
IANACSM (I am not a computer science major) but the algorithm seems to be a standard one taught in CS courses. A google search on the "first fit" algorithm (mentioned in the comments of the code) yields many results such as this one:
* size(block) = n + size(header)
Scan free list for first block with nWords >= size(block)
If block not found
Failure (time for garbage collection!)
Else if free block nWords >= size(block) + threshold*
Split into a free block and an in-use block
Free block nWords = Free block nWords - size(block)
In-use block nWords = size(block)
Return pointer to in-use block
Else
Unlink block from free list
Return pointer to block
*Threshold must be at least size(header) + 1 to leave room for header and link
Threshold can be set higher to combat fragmentation
It's be pretty hard to claim as intellectual property something that's common knowledge....
Check it out
It explains that the system was compromised back in March by a vulnerability that had not yet been patched at the time. The cracker left a behind a trojan to keep getting in, even after the software was patched. Unfortunately, the FSF people didn't realize it had been compromised until recently, so all the backups for the past few months can't be trusted, hence the verification.
Way down in IBM's official response, it dedicates a complete counter claim (#6) to "Breach of GNU General Public License"
76. SCO has taken source code made available by IBM under the GPL, included that code in SCO's Linux products, and distributed significant portions of those products under the GPL. By so doing, SCO accepted the terms of the GPL (pursuant to GPL 5), both with respect to source code made available by IBM under the GPL and with respect to SCO's own Linux distributions.
78. SCO has breached the GPL by, among other things, (1) claiming ownership rights over Linux code, including IBM contributions; (2) seeking to collect and collecting license fees with respect to Linux code, including IBM contributions; (3) copying, modifying, sublicensing or distributing Linux, including IBM contributions, on terms other than those set out in the GPL and after its rights under the GPL terminated; and (4) seeking to impose additional restrictions on the recipients of Linux code, including IBM contributions, distributed by SCO.
If this goes all the way through court, there is no way to avoid a judicial test of the GPL.
So many violations to catch SCO on... you'd think IBM read slashdot....
No person can be charged with the same crime twice.
So, is there some sort of law so that a company can't sue both another company and that company's customers at the same time for the same issue? Otherwise, SCO collects money twice for the same grievance, in the unlikely event that they win. (IBM lawsuit = $3 bn, license = $699x "2.5 million servers" = $1.5 bn (assuming single processor))
Hauled out my little 8" equatorial reflector to a dark sky site Friday night and had spectacular resolution of surface features. Southern polar cap was crystal clear as were many other surface features that I can't describe very well without a map of Mars handy. That was only at 120-240x. 2 years ago, at the last opposition, I looked at Mars through a scientific grade 12" refractor, and it was just a featureless orange ball. This year is much better. The closeness aspect isn't really so much of an improvement (from an observational standpoint) as the lack of dust storms. I just hope I get a chance to point the big refractor at it again this time around.....
I was a MSFS person until about 3 weeks ago, and the difference in purpose is tangible. X-plane will output exactly what forces were acting on the plane to a text file. It's also has a very nice interface for outputting to multiple monitors across the newtwork (e.g. for a full scale simulator). Also, it isn't really gameable, because there are no pre-set scenarios or even an instruction manual (the 15 or so html pages on the CD don't really count). It's not sold as a game either. On the front page of the program's website they show how it's being used to simulate a new aircraft that's never flown in real life. It's not sold in stores and comes in a small brown shipping box with a one page copy of the install readme.
Definitely not a game.
From this article :
While copies of popular blockbusters can be found on the Internet, sometimes days before the movie is released to theaters, computer copies of films are still too large to easily download and are often poor quality copies made using hand-held camcorders.
Music files, by contrast, are smaller and are CD quality, making them easy to share.
Laughed out loud when I read it. As a college student, I'd have to say my personal observations indicate otherwise for the college student population.
135.144 Portable electronic devices.
(a) Except as provided in paragraph (b) of this section, no person may operate, nor may any operator or pilot in command of an aircraft allow the operation of, any portable electronic device on any of the following U.S.-registered civil aircraft operating under this part.
(b) Paragraph (a) of this section does not apply to -
(1) Portable voice recorders;
(2) Hearing aids;
(3) Heart pacemakers;
(4) Electric shavers; or
(5) Any other portable electronic device that the part 119 certificate holder has determined will not cause interference with the navigation or communication system of the aircraft on which it is to be used.
Pacemakers and hearing aids have an excpeption... although I'm surprised to see that electric razors and voice recorders specifically do as well...
Well, I believe the technical definition is when it begins to undergo nuclear fusion.
Technically, neither the white dwarf or neutron star is a "star," but a stellar remnant (i.e. were once stars, but now are only luminous from electron and neutron degenerecy*, respectively).
There is no spectrum discrimination, the pulsar mentioned in this article emits primarily in the radio.
Actually, for cataloging purposes, I believe planets are planned to be treated the same as stellar companions, due to similar methods of detection.
*Either that or Kelvin-Helmholtz contration, someone correct me if I'm wrong
Amendment X
The powers not delegated to the United States by the Constitution, nor prohibited by it to the states, are reserved to the states respectively, or to the people.
-------------
However, in 1819, the Supreme Court ruled in McCollough vs. Maryland that federal laws supercede state laws. More information can be found here.
The ruling states
The States have no power, by taxation or otherwise, to retard, impede, burthen, or in any manner control the operations of the constitutional laws enacted by Congress to carry into effect the powers vested in the national Government.
That's a very good point, but what the article suggests is that in aircraft with fly-by-wire controls (e.g. flight stick goes to computer, computer goes to control surface) you insert in that computer an irrevocable autopilot linked to GPS. Sure, you could shoot it out, but then you're out all controls or have all controls go haywire.
This would work not too well on older aircraft, where the steering it mostly manual, though.
As for approaches to city airports, they could make pilots lives easier by just restricting the airplane to within a certain distance from the runway's glideslope. Presto, landings easier, terrorism harder.
Hmm, are you sure it's that recent? I know they only pardoned Galileo recently, but the church hasn't been teaching geocentric theory for at least a century, if not two.
The Catholic Church has it's own observatory and has been doing genuine scientific work predicated on the earth orbitting the sun for more than 100 years. Also, the pope endorsed the Big Bang theory around 1950 (although there is no dogma, one way or the other on the subject).
If you read the CAA article and download the actual report, you can see it had the following effects:
"-Compass froze or overshot actual magnetic bearing
-VOR and ILS Course Deviation indicator errors with and without error flag
-VOR Navigation to/from reversal
-Instability of indicators"
There are standards. Cellphones and other strong emmitters of EM radiation can't be used on airplanes.
You can't shield the airplane equipment or make it insensitive to EM signals, it's whole point is to receive weak radio signals at high precision. If you shield anything you block signals to cell phones, avionics or both, thus making them useless.
Also, the reason cellphones are so dangerous is that they are close to the detectors on the aircraft. Radiation intensity decreases over distance, thus a huge radar installation 5 km away is less important than a cell phone 10m away.
And the deviations caused are nothing to sneeze at, according to the report, it messes with the CDIs on the ILS indicators. Not good on an instrument approach in zero visibility!
Lastly, what's the big deal about being out of contact with the outside world for a few hours? Why not just relax and enjoy the view?
True of shoulder launched missiles, but I'm not so sure about things like the Aegis SM2's, or fighter launched air-to-air missiles. However, it's safe to say, it's very very unlikely it's a missile.
I'm pretty sure even SM-3 and PAC-3 can't hit targets above 100k feet. Furthermore, even if I am wrong and they could, who has such advanced SAMs other than the US and could deliver them to Texas?
Compared to the main tank, true. But they use thruster rockets right down to the point they drop subsonic, and these thrusters use hypergolic (self igniting) fuels.
Granted, I'm just trying to say the breakup probably wasn't caused by a catastrophic explosion, rather, more likely, something like heat shield failure.
Not at 200,000 feet. Entry interface is at 400,000 feet. Region of maxiumum heating is at 43 miles up, or 227,040 feet. At that point, they're still doing 15,000 miles per hour. They exit ionization blackout 12 minutes before touchdown, still doing 8200 miles per hour. Surviving egress from an aircraft above Mach 1 is dangerous. Above Mach 3, pretty much not surviveable, unless you have some kind of armored escape pod.
Yeah, You're right, I was mistaken... turned out they weren't as far through reentry as I thought. Eternal optimist that I am, I was hoping........
Agreed. I think we need to replace the shuttle system. It's 30 year old technology.
Maybe some good will come of this and convince Congress to budget for that very purpose....
1. No Surface to Air missile can reach above 100k feet.
2. There is almost no fuel on the space shuttle during reentry.
3. Most likely cause of destruction was damage to heat shield.
4. Survival is possible... space shuttle was relatively slow, already mostly throught the atmosphere the crew may have been able to bail out, and they do have parachutes.
5. This does not bode well for manned space exploration
Really? That's funny.... I could have sworn I made some jaws drop at my school's LUG meeting running UT2003 in linux on my Toshiba Satellite notebook....
:)
Flight Simulator 2002, Black and White, Battlefield 1942 all run without any difficulty. Sure, I could have had a somewhat faster desktop than my laptop (1.7 GHz, gf4go) for the same price, but it works adequately for all demands I have placed on it.
Most importantly, there is a nice wireless hookup in my chem lecture, so I can game away instead of falling asleep.
to the debate about what constitutes a moon....
Even if this does turn out to be a natural object, it is probable too small to be of any significance. One of these days we'll have to distinguish between a large boulder in space and a moon. Otherwise we might have to start counting particles of space dust.
...to everyone who commented on how faked the movie looks.
Yes, you could do the same with photoshop... Or better, just look at Star Wars. But most asteroids (and most everything within the solar system other than the planets) are nothing more than little dots on a black field. Contrary to popular belief, much of astronomy is not about pretty pictures.
As for the stars not moving, I'm not familiar with the set up of the Kitt Peak telescope, but they most have some sort of sidereal rate drive motors installed. There isn't much astronomy one can do with a streak.
would be cooling, because otherwise a metal case does just fine.
:)
A watercooling radiatior could be used to cool the system without exposing sensitive electronics to corrosion.
Of course, there's plenty of silicon on the beach if something breaks anyway.
Asteroids zip by the earth fairly often. You can see the closest ones in the Potentially Hazardous Asteroid (PHA) section of the spaceweather.com page.
What is unusual about this one is that it will be 8th magnitude, which will be easily visible in binoculars or a telescope even in a slightly or moderately light-polluted area. Most of the asteroids that zip by are 12th-14th magnitude and therefore only visible in moderate to large aperture telescopes with dark skies.