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Comment Re:Iron Man's Suit Defies Physics -- Mostly (Score 2, Interesting) 279

by John Carmack (#23266718) Attached to: The Science of Iron Man
Hydrogen peroxide powered rocket packs fly for around 30 seconds, because they have a specific impulse of around 125, meaning that one pound of propellant can make 125 pound-seconds of thrust, meaning that it takes about two pounds of propellant for every second you are in the air. Mass ratios are low for anything strapped to a human, so the exponential nature of the rocket equation can be safely ignored.

A pretty hot (both literally and figuratively) bipropellant rocket could manage about twice the specific impulse, and you could carry somewhat heavier tanks, but two minutes of flight on a rocket pack is probably about the upper limit with conventional propellants.

However, an actual jet pack that used atmospheric oxygen could have an Isp ten times higher, allowing theoretical flights of fifteen minutes or so. Here, it really is a matter of technical development, since jet engines have thrust to weight ratios too low to make it practical. There is movement on this technical front, but it will still take a while.

John Carmack
The Internet

Comcast Makes Nice with BitTorrent 161

Posted by Zonk from the friendly-dogs-and-cats dept.
An anonymous reader writes "In a dramatic turn-around of relations, cable provider Comcast and BitTorrent are now working together. The deal comes as BitTorrent tries to put its reputation for illegal filesharing behind it. The companies are in talks to collaborate on ways to run BitTorrent's technology more smoothly on Comcast's broadband network. Comcast is actually entertaining the idea of using BitTorrent to transport video files more effectively over its own network in the future, said Tony Warner, Comcast's chief technology officer. '"We are thrilled with this," Ashwin Navin, cofounder and president of BitTorrent, said of the agreement. BitTorrent traffic will be treated the same as that from YouTube Inc., Google Inc. or other Internet companies, he said. It was important that Comcast agreed to expand Internet capacity, because broadband in the United States is falling behind other areas of the world, Navin said. Referring to the clashes with Comcast, he said: "We are not happy about the companies' being in the limelight."'"

Firefox Usage Climbing 443

Posted by CmdrTaco from the hey-thats-nothing dept.
kbox writes "According to the Amsterdam analytics firm onestat The Firefox browser has jumped from a global market share of 8.7% to a whopping 13% since April 2005. The national usage of Firefox make some interesting reading, too, with Firefox making up 16% in the USA, 24% in Australia and a huge 39% in Germany." Unsurprisingly, on Slashdot we skew the averages somewhat, with Firefox weighing in at 65% of our traffic... but sadly 18% of our Firefox users need to upgrade to the latest version ;) Go do that now.

Patriot Act Bypasses Facebook Privacy 562

Posted by ScuttleMonkey from the if-you-don't-want-it-published dept.
Geoffreyerffoeg writes "An article from the National Association of Colleges and Employers contains yet another horror story about a prospective hire's Facebook being checked — with a different twist. The interviewee had enabled privacy on his profile, '[b]ut, during the interview, something he was not prepared for happened. The interviewer began asking specific questions about the content on his Facebook.com listing and the situation became very awkward and uncomfortable. The son had thought only those he allowed to access his profile would be able to do so. But, the interviewer explained that as a state agency, recruiters accessed his Facebook account under the auspices of the Patriot Act.' How can a 'state agency' use the Patriot Act to subpoena a Facebook profile?"

Virus Trackers Find Malware With Google 113

Posted by Zonk from the bug-hunters dept.
Casper the Angry Ghost writes "Malware hunters have figured out a way to use the freely available Google SOAP Search API, as well as WDSL, to find dangerous .exe files sitting on thousands of Web servers around the world. Queries can be written to examine the internals of web-accessible binaries, thus allowing the hunters to identify malicious code from across the internet." From the article: "We're finding literally thousands of sites with malicious code executables. From hacker forums, newsgroups to mailing list archives, they're all full of executables that Google is indexing. About 15 percent of the results came back from legitimate Web sites hijacked by malicious hackers and seeded with executables."

Japanese Gamers' Post-E3 Reversal 108

Posted by Zonk from the logical-people dept.
Castar writes "Prior to E3, Famitsu readers were interested in the PS3, and Final Fantasy. Post E3, while there's still some excitement over Final Fantasy, they seem to be very interested in the Wii, and concerned about the PS3's high price. It certainly seems that in Japan, at least, Nintendo and Sony's fortunes have reversed. Will this hold through the launch and the succeeding years?" From the article: "Nearly 70% of readers said they are most looking forward to Wii. 21% voted for PlayStation 3, while the others voted for systems already released. 88.4% of readers believe PlayStation 3 is too expensive, while 10% believe it's 'about right'."

'Final Edition' of Blade Runner to be Released 425

Posted by Zonk from the he-was-a-replicant dept.
gevmage writes "CNN reports that a new version of Blade Runner will be released by Warner Home Video in a few months, for the 25th anniversary of the original film's release." From the article: "After a limited theatrical release, the newly spruced-up "Runner" will be released in a multidisc special edition DVD that also will include the original theatrical cut, the expanded international theatrical cut and the 1992 director's cut. Warner said specifics about the two DVD editions will be announced later."

How the PS3 Hit $600 535

Posted by Zonk from the i-blame-mudflation dept.
Joystiq has up an interesting article today, gathering together information from a couple of places to discuss why the PlayStation 3 is so expensive. From the article: "Kutaragi was demoted after being passed over for the role of CEO and, when former Sony Pictures head Howard Stringer assumed the position, the relationship between the content and technology divisions of Sony became even more intimate. Stringer "quickly dubbed the PlayStation 3 as one of the company's 'champion' products." Kutaragi's desire to stratify the console market with Cell technology in effect wed Sony to the unpalatable prospect of charging an unprecedented price. Coupled with Sony's desire to not only push their own content on HD discs, but to control that medium with their proprietary Blu-ray format, the final price was escalated by two very advanced (and very expensive) pieces of Sony technology."

Nintendo's Mario - 26 Years of History 57

Posted by Zonk from the let'sa-go dept.
kukyfrope writes "What started as a guy simply trying to rescue his whiny girlfriend from an angry ape 26 years ago has since grown into one of the most recognizable faces in video gaming: Mario. GameDaily explores the different types of Mario games over the years, from Jump Man to Mario Kart, to the new Wii title, Super Mario Galaxy." From the article: "Mario Bros. was released in a combination cart with the shooting game Duck Hunt, and gamers ate it up aplenty. (It was so popular, in fact, that the game was released for the Game Boy Color and remains one of its highest sellers to date.) Super Mario Bros. 2 would arrive years later and would take a drastic turn in gameplay, as it was actually based on a Japanese game called Doki Doki Panic and not the "true" sequel that was released in Japan only (at the time- it would resurface in the SNES release Super Mario All Stars). It was a hit, and would see a release alongside the launch of the Game Boy Advance years later under the name Super Mario Advance."

Nintendo Learns from Mistakes with GameCube 315

Posted by Zonk from the a-company-that-learns-is-no-company-at-all dept.
kukyfrope writes "Reggie Fils-Aime, Nintendo of America's Executive VP of Sales and Marketing, talks about what went wrong with GameCube and how Nintendo will not make the same mistakes when launching Wii. Reggie admits that the initial software lineup for the GameCube was simply not 'diverse and strong enough from a first and third-party perspective,' and by Nintendo's showing at E3 2006, the Wii will launch with a wide variety of games for may types of gamers."

Nintendo Announces Japanese Wii Price 477

Posted by Zonk from the yay-for-cheap-fun dept.
Wowzer writes "Nintendo has revealed to Famitsu.com, at the company's recent press conference unveiling its financial results, that Wii would arrive in Japanese stores with a maximum price tag of 25,000 yen. After taking in account various factors, the conversion to other currencies comes down to a launch price of: 225 dollars, 225 euros, and 150 pounds." Update: 05/25 13:45 GMT by Z : GamesIndustry.biz points out they hope to ship 6 million units by next March, and an Opera exec has said you can browse the internets with the wiimote.

Sony May Try To Stop PS3 Game Resales 423

Posted by Zonk from the because-we-can't-hate-them-enough dept.
Next Generation reports on Sony's hopes that it will be able to prevent the resale of PS3 games. The article argues that it is unlikely they'll succeed in this goal. From the article: "One expert in retail law told Next-Gen.Biz, 'Sony can theoretically sell a license to play the game, but the user would have to acknowledge acceptance of the license. You've seen this when you install software on a PC. I'm not sure that the license agreement is enforceable if the licensee doesn't agree to it. Also, even if the agreement is enforceable, it's hard to preclude subsequent sale of the disc. The consumer could theoretically agree that he doesn't own the right to transfer his license, but why couldn't he sell the medium that held the license (the disc)? Sony can't enforce the agreement against a third party, as it lacks privity with the third party.'"

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