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We've improved Slashdot's video section; now you can view our video interviews, product close-ups and site visits with all the usual Slashdot options to comment, share, etc. No more walled garden! It's a work in progress -- we hope you'll check it out (Learn more about the recent updates).

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Comment: Re:No KSP at SpaceX? (Score 1) 213

by ClayJar (#48784163) Attached to: SpaceX Rocket Launch Succeeds, But Landing Test Doesn't

The SRBs from Shuttle launches were indeed reused... after a fashion. Each booster was four segments. After each flight and recovery, the boosters were disassembled and the segments renovated and reloaded. The segments were not kept together as a set, so each SRB used in a launch would have four segments each with their own history. (This was expressly noted on NASA TV during each launch, with comments about the oldest and newest segments on the flight and so on.)

As for SpaceX, early Falcon 9 flights had parachutes on the first stage, but the stages did not survive reentry (much less make it all the way to landing). Since you can not land anything large on Mars with parachutes, SpaceX would have eventually had to work on hypersonic retropropulsion, propulsive landings, and so on; they merely pivoted away from the parachute "dead end" and went straight to propulsive recovery with Falcon 9 v1.1.

Facebook

We Need Distributed Social Networks More Than Ello 269

Posted by timothy
from the pick-your-battles dept.
Frequent contributor Bennett Haselton writes: Facebook threatened to banish drag queen pseudonyms, and (some) users revolted by flocking to Ello, a social network which promised not to enforce real names and also to remain ad-free. Critics said that the idealistic model would buckle under pressure from venture capitalists. But both gave scant mention to the fact that a distributed social networking protocol, backed by a player large enough to get people using it, would achieve all of the goals that Ello aspired to achieve, and more. Read on for the rest.
The Internet

Will Fiber-To-the-Home Create a New Digital Divide? 291

Posted by samzenpus
from the have-and-have-nots dept.
First time accepted submitter dkatana writes Having some type of fiber or high-speed cable connectivity is normal for many of us, but in most developing countries of the world and many areas of Europe, the US, and other developed countries, access to "super-fast" broadband networks is still a dream. This is creating another "digital divide." Not having the virtually unlimited bandwidth of all-fiber networks means that, for these populations, many activities are simply not possible. For example, broadband provided over all-fiber networks brings education, healthcare, and other social goods into the home through immersive, innovative applications and services that are impossible without it. Alternatives to fiber, such as cable (DOCSYS 3.0), are not enough, and they could be more expensive in the long run. The maximum speed a DOCSYS modem can achieve is 171/122 Mbit/s (using four channels), just a fraction the 273 Gbit/s (per channel) already reached on fiber.
Earth

Designer Creates a Water Bottle That You Can Eat 171

Posted by samzenpus
from the eating-trash dept.
Diggester (2492316) writes "Rodrigo García González has been working on the Ooho water bottle for the past few years. The bottle is made out of edible materials, looks like a jellyfish, and has the potential to put an end to the bottled water industry. Inspired by the juice-filled pearls added to bubble tea and the mad-cuisine creations of chef Ferran Adriá, who uses a technique known as sheperification (encasing liquid into edible membranes), García is on his way to revolutionizing the bottled water industry."

Comment: Re:Shooting themselves in the foot (Score 1) 229

by ClayJar (#46487155) Attached to: Elon Musk Addresses New Jersey's Tesla Store Ban

"Our stores will transition to being galleries, where you can see the car and ask questions of our staff, but we will not be able to discuss price or complete a sale in the store. However, that can still be done at our Manhattan store just over the river in Chelsea or our King of Prussia store near Philadelphia."

Sales over the border? Already ready. Collecting tax revenue? If NJ is anything like my state, they'll collect that when you register the vehicle in NJ. The state isn't going to be out much money, but the dealers are protected by the politicians who get their campaign contributions, and neither has to give a hoot about inconveniencing the people. (The people inconvenienced weren't going to buy from the dealers, so no money lost there, and they aren't numerous enough to make a dent in the elections, so that's all fine and dandy, too.)

Comment: Re:Won't they hit the ISS on a future orbit? (Score 5, Informative) 52

by ClayJar (#45483593) Attached to: ISS Astronauts Fire-Up Awesome 'Cubesat Cannon'

They're launched from the nadir side in a nadir-aft 45-degree direction to prevent collision with the ISS. That imparts a small negative delta-V (with insertion velocity between 1.1 and 1.7 m/s), so their orbit would begin just slightly below the ISS. Additionally, one of the requirements for CubeSats launched from J-SSOD is that they have a ballistic coefficient of 120 kg/m^2 or less. This means that their orbits will decay faster than the ISS orbit, precluding any potential for collisions over time.

(The life expectancy on orbit of a CubeSat launched from J-SSOD is something like 100-150 days, depending on orbital parameters as of deployment, solar activity, etc.)

Announcements

Come Try Out Slashdot's New Design (In Beta) 1191

Posted by timothy
from the we-show-you-tell dept.
Slashdot's biggest redesign effort ever is now in beta and you're invited to help guide it. This redesign has been shaped by feedback from community members over the past few months (a big thanks to those of you who participated in our alpha testing phase!), and we'd like your thoughts on it, too. This new design is meant to be richer but also simpler to use, while maintaining the spirit of what Slashdot is all about: News for Nerds. Stuff that matters. Read on for the details of what's included, or read this blog post. Update: 10/02 19:16 GMT by T : Since this post went live, we've been reading through the comments below as well as your (hundreds!) of emails. These are all valuable, as we continue to implement our current features into the Beta. Keep 'em coming; we love the feedback. Please keep in mind that this is called Beta for a reason; we've still folding in lots of improvements. One important thing to bear in mind is that the images are optional: check out the Classic mode by clicking on the view selection widget (just above the stories) on the Beta page.

Comment: The first stage is suborbital. (Score 5, Interesting) 127

by ClayJar (#44572559) Attached to: The Grasshopper Can Fly Sideways

Heat shields are the efficient way to slow from orbital speeds for reentry (e.g. the Shuttle), but conveniently for recovery the first stage isn't orbital. Grasshopper is basically a modified Falcon 9 first stage, and the goal of the testing is recovery of the first stage of Falcon 9-R, which is much easier than reentry from orbit..

We're not talking single stage to orbit here, and recovery of the second stage would certainly involve a heat shield. The first stage is a different animal. SpaceX seems to be intending to use a boost-back trajectory concept. I look forward to seeing how that works. (The controlled water "landing" attempt will be something to see, too, of course.)

Comment: Leatherman killed the tool market. (Score 5, Funny) 333

by ClayJar (#42295033) Attached to: Will Tablets Kill Off e-Readers?

Leatherman killed the tool market when it came out. Why buy a single-purpose tool when you can get many more features for a little bit more money?

Sometimes having something that *doesn't* slice, dice, and julienne fries is the better choice. I mean, sure, I could do many small repairs using just a leatherman, but a nice set of wrenches and drivers makes working on my bike *much* nicer. Or how about crescent wrenches (or shifting spanners, as the case may be)? You can handle all variety of nuts, bolts, and fittings. SAE, metric, square, hex? All are open to you. Yet anyone who spends much time working on mechanical things knows that a crescent wrench, while convenient, is often vastly inferior to a good set of wrenches.

When I'm out on a ride, I carry a small multitool that *does* do a bunch of things in one small, inexpensive, unobtrusive package, just as when I'm out and about, I can get some reading done on my Nexus 7. The Nexus 7 is convenient, but if I ever broke my e-ink Kindle, I'd have a replacement ordered that very day. E-ink readers are basically designed to fill the niche of "electronic trade paperback for avid readers". They fill that niche exceedingly well, and avid readers are a renewable resource.

Comment: Awkward... (Score 5, Interesting) 599

by ClayJar (#42288727) Attached to: Why <em>The Hobbit's</em> 48fps Is a Good Thing

Actually, I was thinking more along the lines of the Hogfather (specifically from the movie).

While I enjoyed this first Hobbit movie, I found the Radagast scenes awkward (like an old family photo with too-large glasses and sisters with poofy bangs). Radagast and his bunny sled seemed too much like something right out of Discworld, which would be delightful except that combining Discworld and Middle Earth yields a very large impedance mismatch.

Power

Ask Slashdot: What Stands In the Way of a Truly Solar-Powered Airliner? 590

Posted by Soulskill
from the i-blame-gravity dept.
centre21 writes "I've been reading about solar-powered aircraft all over the Internet, as well as solar power in general. But I'm wondering: is it more than just solar cell efficiency that's preventing the creation of a solar-powered airliner? Conspiracy views aside (which may be valid), it seems to me that if I were running an airline the size of United or American, eliminating the need for jet fuel as a cost would be highly appealing. So, I'm asking: what stands in the way of creating true solar-powered airliners?"
Mars

Curiosity Rover Sees Solar Eclipse On Mars 46

Posted by samzenpus
from the differenet-view dept.
SchrodingerZ writes "Though solar eclipses are fairly common on Earth (much more in the southern hemisphere), yesterday the Mars Curiosity Rover caught sight of a partial solar eclipse in Gale Crater on the Red planet. The martian moon Phobos took a small bite out of the sun on the 37th day (Sol 37) of the rover's martian mission. The Curiosity Rover was able to take a picture of the rare event through a 'neutral density filter that reduced the sunlight to a thousandth of its natural intensity.' This protects the camera from the intense light rays seen during an eclipse or looking directly at the sun. It is possible a short movie of the event could be compiled from the data in the near future. More solar transits of Mars's moon (including the second moon Deimos) are predicted to happen in the days to come."
Handhelds

Amazon Debuts Kindle Paperwhite, Kindle Fire HD In 2 Sizes 307

Posted by timothy
from the plus-they-wash-your-back dept.
Nerval's Lobster writes "Amazon used a Sept. 6 event in California to debut a range of products, including a front-lit [not back-lit, as originally reported] Kindle e-reader with a higher-resolution screen, an updated Kindle Fire, and the new Kindle Fire HD in two screen sizes. First, Bezos showed off a new version of the Kindle e-reader, the Kindle Paperwhite, complete with a front-lit, higher-resolution screen (221 pixels-per-inch and 25 percent more contrast, according to Amazon). The device weighs 7.5 ounces and is 9.1mm thin; battery life is rated at eight weeks, and the screen brightness is adjustable. He then showed off the updated Kindle Fire, before moving to the Kindle Fire HD, which features a choice of 7-inch or 8.9-inch screens, dual stereo speakers with Dolby Digital Plus, two antennas for better Wi-Fi pickup, and a Texas Instruments OMAP 4470 processor (which Bezos claimed could out-perform the Tegra 3). The Kindle Fire HD's 7-inch version will retail for $199 and ship Sept. 14, while the 8.9-inch version will cost $299 and ship Nov. 20. An 8.9-inch, 4G LTE-enabled version with 32GB storage will be available starting Nov. 20 for $499, paired with a $49.99-a-year data plan."

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