No (human) spacecraft to date has used the solar wind for propulsion - the solar sail is the only realistic mechanism for doing so, and that's never actually been tried (there was to have been a test of the Cosmos 1 couple of years ago but it suffered a launch failure).
First off, you mean solar pressure, not the solar wind. The solar wind is a bunch of ions shooting out of the Sun... Solar sails will use solar pressure from the Sun's light for propulsion.
Every spacecraft flown is acted on by Solar Pressure... you can measure the way solar pressure defelcts the spacecraft trajectory quite easily. Several spacecraft have been flown that use solar pressure to generate a torque for attitude control. Several others have used solar pressure for small trajectory corrections... Mariner 10, Magellen...
This article is crackpot Science. Solar Pressure is a well known effect and solar sails are a proven concept.
At work, we just bechmarked the Dell systems a month ago and got very similar results to Apple for the "base" rate. The article seems to be quoting the "peak" rate for the Dells. It's not valid to compare peak rates yet because gcc 3.3 and os 10.3 aren't really fully optimized yet.
The article also complains that using the NAGWare compilers is not a valid test since they're too slow. But I think the NAGWare compiler is a more vallid comparison than intel's compiler because most real-world computing is done with NAGWare because it fully implements the F95 spec and is more portable. In addition NAGWare is well tested for accuracy and it also very much cheaper.
The Dell benchmark numbers are pure fantasy. They never occur in real-world use.
Hardware problem. On Quartz Extreme machines, the mouse pointer is actually drawn by the graphics hardware. It's not drawn by the CPU at all. If your mouse pointer stops moving, you either have a hardware problem with your graphics board, or possibly a USB problem.
I have an old 500 mhz G3 with no Quartz Extreme goodness. It's also a powerbook so the mouse and keyboard are not USB.
And anyway genius, It's possible to write a cocoa app the blocks the window manager and makes the machine unresponsive... I think it is certainly possible to write bad java to do the same...
lots of things can go wrong and do go wrong. Single event upsets and all of that, hardware failures, etc. Unless you are onimpresent and omnipotent don't tell me that my machine didn't lock up. it did. no big deal.
The bald-faced lies are what invoked the cry of "troll." Opera? Please
no lies here, most certainly not bald-faced ones. no trolls niether, just a few idiots.
Wrong. The application was unresponsive. It could be killed remotely to restore the system to a functioning state, right? That means the application was hung. You could have just killed it with a force-quit.
In my case the whole window-manager wasn't responding, I couldn't even move the mouse. Perhaps if I were more patient it would've returned... but ssh'ing in and killing Safari fixed the problem immediately.
This was a one time event, if I could've reproduced it I would've sent a bug report in.... but I haven't seen it again.
So, maybe you think I imagined it, but I maitain that it is possible for an app to make the OS X window manager unresponsive.
No, it's not. The computer doesn't get "beach-balled." Individual applications get "beach-balled." An application gets "beach-balled" when there are unprocessed events waiting in its event queue. Applications can be killed in this state. This is not a freeze.
Very true. But someone unfamiliar with Macs may not know that they can simply switch to another App while Safari is beach-balled. Yeah, I know the mouse gives visual feedback that only one App is busy, etc,etc. But someone unfamiliar with Macs may not notice that and conclude that Safari freezes all of the time.
Yeah, such a conclusion would be mistaken.... but being wrong doesn't make someone a troll.
Job's comments were spot-on. He was blunt and rude so that they would listen to his points and they were really lucky to get advice from someone with Job's experience, and they should have listened instead of getting irritated and trying to get back to their meeting agenda. Agendas should be used to help start a discussion, not to stop it!
The account made the Segway people sound like amateurs who suddenly found themselves playing in the major leagues. Jobs was doing them a favor by playing the role of a grizzled old coach and being very blunt in trying to talk them out of doing some stupid things.
I wish I could get Steve Jobs to stay up all night thinking about my new product! They should've listened more to what he had to say.
I think this would happen if Apple released OS X for intel, but releasing Cocoa for windows just means that windows developers will start using a development environment that is native to OS X.... I'd think this would mean more OS X Apps, and probably more Mac users as a result.
Cocoa apps will always run better on OS X than windows anyway. At the very least, display PDF will probably only work right under OS X.
Wrong. If you could log in remotely, your computer was not frozen. (It's not possible to free OS X unless there's a kernel bug.)
The window manager was frozen. The interface was unresonsive. Hence frozen.
A troll is a person who posts comments that he does not really mean in an effort to generate responses. It comes from the verb "to troll" which means to drag bait in the water and see what bites.
You can't redefine terms like 'frozen' and 'troll' just so that you win an arguement. dipshit. how does the above definition apply to my post or to the original post in this thread??
The original post made a valid point about the openess of Safari's architecture and made a comment about how he strongly prefers opera because safari freezes.
You don't even know what he meant by freezes... he could just mean that his computer is beach-balled by safari which is a very common thing... but to make up some wierd definition of frozen as the kernal somehow locking up and then calling him a troll because that is impossible is just plain dumb. If his says that Safari froze, it prolly ain't got nothing to do with the kernal.
When most ppl say the "computer is frozen" they mean the interface. The interface was frozen... nor kernal panic, just no response from the window manager.
And I have had one kernal panic because of Safari.... I have an old G3 and I see more of this stuff.
Only a troll would claim that Safari froze his computer (literally impossible)
I like Safari. I use Safari every day. Safari once froze my computer and I had to ssh in to kill the process.... though I suspect it was some bad java causing indigestion for my old G3 -which you may not want to blame Safari for.
Since I have experienced something that you think is impossible, I must be a troll and it is your high duty to mod me down....
But first, you might want to spend a few minutes with google and find out what a troll really is. Dipshit.
Perhaps a case could be made for the post as flamebait, but it is most certainly not a troll.
And if you're moderating, you shouldn't post to a discussion as an A/C or under another log in. That makes you an ass in addition to being a dipshit.
And since I'm bitching about moderators and burning Karma today anyway.... why are all of the standard pro-MS and anti-MS rants getting modded up instead of modded as off-topic? Such moderation is only decreasing the signal-to-noise ratio. It's hard to find any actual discussion of Safari or what this means for Apple.
Apple should port Safari to Windows along with all of the Cocoa libraries. Tell developers that if they develop in Cooca, a windows port is just a re-compile away. Without Cocoa on Windows, you not only have to re-write everything you have to change languages too!
Windows actually started as a set of libraries for DOS programs to add GUIs. The library's popularity helped Windows beat out GEM and OS/2 and achieve total world domination. Apple could pull a similar trick with Win-Cocoa.
If apple ported the Cocoa Foundation, AppKit, and WebKit to windows, Linux, Solaris, etc. a lot of developers would develop in Cocoa simply because of how wonderful Cocoa is.... and even if Cocoa apps ran under Windows and Linux, they would still run best on OS X on a Mac....same strategy as the iPods....
Microsoft felt that customers were better served by using Apple's browser, noting that Microsoft does not have the access to the Macintosh operating system that it would need to compete
This is utter crap. Omnigroup is basing the new Omniweb off of the Safari rendering engine. They can do this because it is open source. Safari's Webcore may be part of OS X now, but the interface is documented and anyone can write a web browser to use it.
The article raves about Win Media 9s quality and how it's good enough for a theater and all....
Does anyone know how Win Media-9's quality compares to MPEG-4 and Quicktime? Is MS's new codec really as big a breakthrough as the article claims? Does this mean Apple's behind the curve with MPEG-4 or is MS just blowing smoke?
The article claims that the address system can also be used for satellites:
Moreover, the system is flexible. By adding characters, NACs can also represent a point in, around or above the earth, using the centre of the earth as a reference point. This is handy for pinpointing areas underground for mining companies, or in space for orbiting satellites.
However, this would only work for geostationary satellites... satellites which move over the surface would have continually changing addresses.
The whole system seems kinda moronic to me... It would be better to just be able to latitude and longitude down for addresses.... at least that code is human readable... all this system does is obfuscate lat and lon into some propriatary address format so they can make royalties.
They probably took the picture between DSN tracking passes. There are three DSN stations: Goldstone, California, Madrid, Spain, and Canberra, Australia. In the picture it looks like the Southern hemisphere has the best view of Mars, so they were probably using Canberra for their downlink... so they took the picture when Canberra was out of view.
So rather than try and take a picture of south America, they were probably just avoiding taking a picture of Australia
If throw-away is cheaper, why not use throw-away? The exhaust from the shuttle's solids does more damage to the environment than a (LOX-LH) Saturn V launch including whatever rocket parts end up in the ocean.
A Saturn V could lift the space station in much fewer launches than the space shuttle... which would be an even greater cost savings, and a bigger plus for the environment.
My whole point is that a multiple stage expendable rocket is the optimal way to do space launches as long as you're using chemical rockets. If we figure out fusion rockets, then maybe a reusable rocket makes sense... but until then, projects like the X-33 are fool's errands.
I think Beal aerospace was on the right track in designing expendible rockets to uses cheap technology and non-toxic fuels. Too bad the economics weren't worked out.
"No. The problem is the 1970s technology made them too high maintenance."
Yeah, well then they should have used 1960s technology. Saturn V rockets were cheaper to launch than Shuttles and they outperformed shuttles. Suyuz rockets are cheaper than shuttles. The Shuttles are the result of some cold war political goal to best the soviets by trying to build a reusable rocket.... If they would have set out to build a cheaper rocket they would have stuck with expendibles.
The orbital space plane is finally setting out cheaper as a major design goal. Oddly, it turns out that the Apollo command module would meet the OSP requirements, and one of the teams is proposing rebuilding the command module as their entry into the OSP competition.
According to Fortune: "The iTunes Music Store will initially offer 200,000 tunes, paying the record companies an average of 65 cents for each track it sells."
Apple gets $.99 for singles, but less for albums (I bought a 20 track album fo $9.99)... and I'm sure that they need to pay the credit card companies some percentage, and then pay Akamai for the servers, and Amazon for the one-click patents... so I doubt they make more that 15 cents per song on average... but that's still a good margin... but more like $40,000 than El Reg's $100,000 estimate
I'd like to be able to make a wish list of all of the songs and albums that I want, put it in iTunes and tell it to spend $30 a month.... the current set up tends to make me impulse buy lots and lots of songs and spend way to much money:) I think I'll have to give up vending machine cokes to support my music habit...
The problem with leap seconds is that they are not predictable. You can work out some future event in TAI, but you cannot convert it to UTC because you don't know when the next leap second will happen.
If you work in UTC to plan something in the future (say a space mission 4-10 years from now) you can suddenly find all of your schedule off by a second (or more) when a leap second is added or subtracted.
Of course, everything is usually tied to the wall clock which is tied to UTC an not TAI... so there's always a danger that a schedule laid out before a leap second is added can be off... and being off by a second is a big deal in a space mission when you're going several kilometers per second.
I say scrap leap seconds until someone can come up with a reliable model of the Earth's rotation so that leap seconds can be predicted instead of being random. When accuracy to the second matters, who the hell wants a random offset on their clock?
A lot of current mars missions tell time by what Mars longitude the Sun is over. If you know the longitude where your rover or lander is, a simple subtraction tells you how high the sun is in the sky. No need for leap seconds as the clock is directly tied to the Sun's position.
Use Julian dates if you want a decimal time. Astronomers have been using this for a long, long time... Noon on Jan 1 , 2000 is Julian date 2451545.0. Use this number to convert your time to a Julain date. BTW, Julian days switch from one day to the next on noon rather than midnight because astonomers tend to work nights:)
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No (human) spacecraft to date has used the solar wind for propulsion - the solar sail is the only realistic mechanism for doing so, and that's never actually been tried (there was to have been a test of the Cosmos 1 couple of years ago but it suffered a launch failure).
First off, you mean solar pressure, not the solar wind. The solar wind is a bunch of ions shooting out of the Sun... Solar sails will use solar pressure from the Sun's light for propulsion.
Every spacecraft flown is acted on by Solar Pressure... you can measure the way solar pressure defelcts the spacecraft trajectory quite easily. Several spacecraft have been flown that use solar pressure to generate a torque for attitude control. Several others have used solar pressure for small trajectory corrections... Mariner 10, Magellen...
This article is crackpot Science. Solar Pressure is a well known effect and solar sails are a proven concept.
At work, we just bechmarked the Dell systems a month ago and got very similar results to Apple for the "base" rate. The article seems to be quoting the "peak" rate for the Dells. It's not valid to compare peak rates yet because gcc 3.3 and os 10.3 aren't really fully optimized yet.
The article also complains that using the NAGWare compilers is not a valid test since they're too slow. But I think the NAGWare compiler is a more vallid comparison than intel's compiler because most real-world computing is done with NAGWare because it fully implements the F95 spec and is more portable. In addition NAGWare is well tested for accuracy and it also very much cheaper.
The Dell benchmark numbers are pure fantasy. They never occur in real-world use.
Hardware problem. On Quartz Extreme machines, the mouse pointer is actually drawn by the graphics hardware. It's not drawn by the CPU at all. If your mouse pointer stops moving, you either have a hardware problem with your graphics board, or possibly a USB problem.
I have an old 500 mhz G3 with no Quartz Extreme goodness. It's also a powerbook so the mouse and keyboard are not USB.
And anyway genius, It's possible to write a cocoa app the blocks the window manager and makes the machine unresponsive... I think it is certainly possible to write bad java to do the same...
lots of things can go wrong and do go wrong. Single event upsets and all of that, hardware failures, etc. Unless you are onimpresent and omnipotent don't tell me that my machine didn't lock up. it did. no big deal.
The bald-faced lies are what invoked the cry of "troll." Opera? Please
no lies here, most certainly not bald-faced ones. no trolls niether, just a few idiots.
Wrong. The application was unresponsive. It could be killed remotely to restore the system to a functioning state, right? That means the application was hung. You could have just killed it with a force-quit.
In my case the whole window-manager wasn't responding, I couldn't even move the mouse. Perhaps if I were more patient it would've returned... but ssh'ing in and killing Safari fixed the problem immediately.
This was a one time event, if I could've reproduced it I would've sent a bug report in.... but I haven't seen it again.
So, maybe you think I imagined it, but I maitain that it is possible for an app to make the OS X window manager unresponsive.
No, it's not. The computer doesn't get "beach-balled." Individual applications get "beach-balled." An application gets "beach-balled" when there are unprocessed events waiting in its event queue. Applications can be killed in this state. This is not a freeze.
Very true. But someone unfamiliar with Macs may not know that they can simply switch to another App while Safari is beach-balled. Yeah, I know the mouse gives visual feedback that only one App is busy, etc,etc. But someone unfamiliar with Macs may not notice that and conclude that Safari freezes all of the time.
Yeah, such a conclusion would be mistaken.... but being wrong doesn't make someone a troll.
Job's comments were spot-on. He was blunt and rude so that they would listen to his points and they were really lucky to get advice from someone with Job's experience, and they should have listened instead of getting irritated and trying to get back to their meeting agenda. Agendas should be used to help start a discussion, not to stop it!
The account made the Segway people sound like amateurs who suddenly found themselves playing in the major leagues. Jobs was doing them a favor by playing the role of a grizzled old coach and being very blunt in trying to talk them out of doing some stupid things.
I wish I could get Steve Jobs to stay up all night thinking about my new product! They should've listened more to what he had to say.
I think this would happen if Apple released OS X for intel, but releasing Cocoa for windows just means that windows developers will start using a development environment that is native to OS X.... I'd think this would mean more OS X Apps, and probably more Mac users as a result.
Cocoa apps will always run better on OS X than windows anyway. At the very least, display PDF will probably only work right under OS X.
Wrong. If you could log in remotely, your computer was not frozen. (It's not possible to free OS X unless there's a kernel bug.)
The window manager was frozen. The interface was unresonsive. Hence frozen.
A troll is a person who posts comments that he does not really mean in an effort to generate responses. It comes from the verb "to troll" which means to drag bait in the water and see what bites.
You can't redefine terms like 'frozen' and 'troll' just so that you win an arguement. dipshit. how does the above definition apply to my post or to the original post in this thread??
The original post made a valid point about the openess of Safari's architecture and made a comment about how he strongly prefers opera because safari freezes.
You don't even know what he meant by freezes... he could just mean that his computer is beach-balled by safari which is a very common thing... but to make up some wierd definition of frozen as the kernal somehow locking up and then calling him a troll because that is impossible is just plain dumb. If his says that Safari froze, it prolly ain't got nothing to do with the kernal.
When most ppl say the "computer is frozen" they mean the interface. The interface was frozen... nor kernal panic, just no response from the window manager.
And I have had one kernal panic because of Safari.... I have an old G3 and I see more of this stuff.
Does it have the Application Kit and the Foundation? Is it enough to port a Cocoa App over?
Only a troll would claim that Safari froze his computer (literally impossible)
I like Safari. I use Safari every day. Safari once froze my computer and I had to ssh in to kill the process.... though I suspect it was some bad java causing indigestion for my old G3 -which you may not want to blame Safari for.
Since I have experienced something that you think is impossible, I must be a troll and it is your high duty to mod me down....
But first, you might want to spend a few minutes with google and find out what a troll really is. Dipshit.
Perhaps a case could be made for the post as flamebait, but it is most certainly not a troll.
And if you're moderating, you shouldn't post to a discussion as an A/C or under another log in. That makes you an ass in addition to being a dipshit.
And since I'm bitching about moderators and burning Karma today anyway.... why are all of the standard pro-MS and anti-MS rants getting modded up instead of modded as off-topic? Such moderation is only decreasing the signal-to-noise ratio. It's hard to find any actual discussion of Safari or what this means for Apple.
Apple should port Safari to Windows along with all of the Cocoa libraries. Tell developers that if they develop in Cooca, a windows port is just a re-compile away. Without Cocoa on Windows, you not only have to re-write everything you have to change languages too!
....same strategy as the iPods....
Windows actually started as a set of libraries for DOS programs to add GUIs. The library's popularity helped Windows beat out GEM and OS/2 and achieve total world domination. Apple could pull a similar trick with Win-Cocoa.
If apple ported the Cocoa Foundation, AppKit, and WebKit to windows, Linux, Solaris, etc. a lot of developers would develop in Cocoa simply because of how wonderful Cocoa is.... and even if Cocoa apps ran under Windows and Linux, they would still run best on OS X on a Mac
Microsoft felt that customers were better served by using Apple's browser, noting that Microsoft does not have the access to the Macintosh operating system that it would need to compete
This is utter crap. Omnigroup is basing the new Omniweb off of the Safari rendering engine. They can do this because it is open source. Safari's Webcore may be part of OS X now, but the interface is documented and anyone can write a web browser to use it.
The article raves about Win Media 9s quality and how it's good enough for a theater and all....
Does anyone know how Win Media-9's quality compares to MPEG-4 and Quicktime? Is MS's new codec really as big a breakthrough as the article claims? Does this mean Apple's behind the curve with MPEG-4 or is MS just blowing smoke?
How about: GPWNUBINUAAL or "GNU Previously Was Not Unix But Is Now Unix After Apple's Lawsuit"
That'd be a great distro!
I never liked "GNU/Linux"... it's sounds kinda hokey... but "GNU/Unix" has a nice ring to it...
:)
You get everything, Unix and Not-Unix all rolled together
Just look at the rate of failure for early moon missions
It's a hard probelm to send a probe to the Moon or Mars. landing and aerocapture at Mars are dicy things.
The article claims that the address system can also be used for satellites:
Moreover, the system is flexible. By adding characters, NACs can also represent a point in, around or above the earth, using the centre of the earth as a reference point. This is handy for pinpointing areas underground for mining companies, or in space for orbiting satellites.
However, this would only work for geostationary satellites... satellites which move over the surface would have continually changing addresses.
The whole system seems kinda moronic to me... It would be better to just be able to latitude and longitude down for addresses.... at least that code is human readable... all this system does is obfuscate lat and lon into some propriatary address format so they can make royalties.
They probably took the picture between DSN tracking passes. There are three DSN stations: Goldstone, California, Madrid, Spain, and Canberra, Australia. In the picture it looks like the Southern hemisphere has the best view of Mars, so they were probably using Canberra for their downlink... so they took the picture when Canberra was out of view.
So rather than try and take a picture of south America, they were probably just avoiding taking a picture of Australia
If throw-away is cheaper, why not use throw-away? The exhaust from the shuttle's solids does more damage to the environment than a (LOX-LH) Saturn V launch including whatever rocket parts end up in the ocean.
A Saturn V could lift the space station in much fewer launches than the space shuttle... which would be an even greater cost savings, and a bigger plus for the environment.
My whole point is that a multiple stage expendable rocket is the optimal way to do space launches as long as you're using chemical rockets. If we figure out fusion rockets, then maybe a reusable rocket makes sense... but until then, projects like the X-33 are fool's errands.
I think Beal aerospace was on the right track in designing expendible rockets to uses cheap technology and non-toxic fuels. Too bad the economics weren't worked out.
"No. The problem is the 1970s technology made them too high maintenance."
Yeah, well then they should have used 1960s technology. Saturn V rockets were cheaper to launch than Shuttles and they outperformed shuttles. Suyuz rockets are cheaper than shuttles. The Shuttles are the result of some cold war political goal to best the soviets by trying to build a reusable rocket.... If they would have set out to build a cheaper rocket they would have stuck with expendibles.
The orbital space plane is finally setting out cheaper as a major design goal. Oddly, it turns out that the Apollo command module would meet the OSP requirements, and one of the teams is proposing rebuilding the command module as their entry into the OSP competition.
According to Fortune: "The iTunes Music Store will initially offer 200,000 tunes, paying the record companies an average of 65 cents for each track it sells."
Apple gets $.99 for singles, but less for albums (I bought a 20 track album fo $9.99)... and I'm sure that they need to pay the credit card companies some percentage, and then pay Akamai for the servers, and Amazon for the one-click patents... so I doubt they make more that 15 cents per song on average... but that's still a good margin... but more like $40,000 than El Reg's $100,000 estimate
I'd like to be able to make a wish list of all of the songs and albums that I want, put it in iTunes and tell it to spend $30 a month.... the current set up tends to make me impulse buy lots and lots of songs and spend way to much money :) I think I'll have to give up vending machine cokes to support my music habit...
The problem with leap seconds is that they are not predictable. You can work out some future event in TAI, but you cannot convert it to UTC because you don't know when the next leap second will happen.
If you work in UTC to plan something in the future (say a space mission 4-10 years from now) you can suddenly find all of your schedule off by a second (or more) when a leap second is added or subtracted.
Of course, everything is usually tied to the wall clock which is tied to UTC an not TAI... so there's always a danger that a schedule laid out before a leap second is added can be off... and being off by a second is a big deal in a space mission when you're going several kilometers per second.
I say scrap leap seconds until someone can come up with a reliable model of the Earth's rotation so that leap seconds can be predicted instead of being random. When accuracy to the second matters, who the hell wants a random offset on their clock?
A lot of current mars missions tell time by what Mars longitude the Sun is over. If you know the longitude where your rover or lander is, a simple subtraction tells you how high the sun is in the sky. No need for leap seconds as the clock is directly tied to the Sun's position.
Use Julian dates if you want a decimal time. Astronomers have been using this for a long, long time... Noon on Jan 1 , 2000 is Julian date 2451545.0. Use this number to convert your time to a Julain date. BTW, Julian days switch from one day to the next on noon rather than midnight because astonomers tend to work nights :)