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

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

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

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

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

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

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

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

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."
Science

Virtual Nanoscopy Allows Scientists To Capture High Res Cell Map 16

hypnosec writes "Researchers have managed to generate ultra-large high resolution electron microscopic maps of cells by developing new tools that can combine thousands of images taken from an electron microscope thus enabling them to view a cell in its entirety. Use of electron microscopes reveals intricate structures of cells, but with a limitation that only a tiny portion of the cell is captured, which misses the bigger picture. If low-res images are captured to view a greater part of the biological structure, intricate details are missed. A team of scientists over at Leiden University Medical Center in the Netherlands has come up with a technique called 'virtual nanoscopy' that enabled them to ultrastructurally map regions of cells and tissue as large as 1 mm^2 at nanometer resolution."
Games

Linux Users Banned From Diablo III Servers 518

dartttt writes with word that "Blizzard has banned all Linux users who are playing Diablo III on Linux using Wine." Reader caranha adds that these users have been flagged as "using cheating programs," and that replies from Blizzard support staff so far have upheld these bans. Update: 07/03 16:57 GMT by S :An official response from a Blizzard Community Manager indicates they don't ban people for using Linux. As with most reports of game bans, we have only the word of random gamers that they were banned for the reason they say they were banned.

Comment Intentionally once for me. (Score 4, Interesting) 566

I can't speak for his experience, but I can tell my own story about being intentionally run down by a motor vehicle.

It was a dark and stormless night (hehe). To be specific, it was late on the Wednesday night before Thanksgiving, and I was riding across town to drop some goodies off at a friend's place. We have virtually no bike paths, and those we have tend not to be connected to anything, so it's all road riding here. The road was one of those five-lane jobs (two in each direction and a suicide left in the middle), and traffic was extremely sparse. (We're talking maybe half a dozen cars total at the busiest intersection along the route.)

When that light with maybe half a dozen vehicles turned green, I rode on and was passed by the cars that had been waiting. Not far down the road one of them, a pickup truck, moved into the suicide left lane as if he was going to turn into some apartments, but he didn't immediately complete the turn in spite of no oncoming traffic. As I approached (two lanes away, riding near the white stripe on the outside edge of the outside lane), all of the sudden I saw his white reverse lights come on. He floored it and cranked the wheel around, backing hard across both lanes in my direction and continuing all the way into a doctor's office parking lot.

Had I been expecting it, I could likely have quick-turned a bit harder to avoid the hit, but you don't expect someone to try to injure or kill you. So, my turn wasn't quite hard enough, and I went into the side of the pickup as my bike went down. The guy continued back, crushing my front wheel, then paused for a moment before peeling out and driving off. My reaction wasn't quick enough to avoid the assault, but it was just fast enough to let me escape with a broken bike and only minor injuries (scrapes and bruises, mainly).

So, a pickup truck stops in the middle of the road for no reason, waits for the bike, throws it into reverse, and floors it across both lanes and into a parking lot. Can't get much more blatant than that. Moments after the guy drove off, a car pulled into the parking lot to check how badly I was injured. He had seen the whole thing and was virtually dumbfounded. He had never seen something like that in his life, he said, although I'd hope most people would fall into that category. I got a very close and intimate look at the pickup truck (obviously). I had a witness who saw the whole thing. So, why didn't anything come of it? The guy had an illegally obscured license plate. Without being able to ID the vehicle, the police would be happy to take a statement from me, but that was the extent of it.

The vast majority of car/bike incidents I've had are simply oblivious drivers, e.g. passing too closely or returning to your lane before the back of their vehicle has passed you. Even antagonistic drivers are often so due to ignorance, e.g. "Get on the sidewalk!" (which is not only dangerous but also expressly against the law here). Still, every so often you get a psychopath. What can you do (other than mounting a few Go Pro cameras around your bike to gather and preserve evidence)?

Comment Re:A tsunami in deep water is a non-event. (Score 1) 332

You are correct. A ship can take much larger waves directly into the bow than it can take abeam. It's perfectly logical if you think about it. The bow is designed to plow into the water, so it'll deflect the wave energy better, and designers know storms will come, so they design to some extent or another for waves breaking over the bow. Waves running directly into the side have a large surface to work on.

Additionally, consider the simple geometry. A ship is going to be much more stable in the pitch axis (where it is a nice, long lever) than in the roll axis (where it's much closer to a round log). Tipping a ship end-over-end would require something more like a Michael Bay movie, while capsizing it by rolling it over requires much less force.

The images I've seen of this ship show something much more like a floating rig platform than a plain old large yacht. It has a long axis, but it's much wider than a "normal" ship. That being the case, it would have more stability in the long axis, but it should be stable enough in the short axis. You *could* just go ahead and build a platform instead of a ship, with deep ballasts well below wave action attached by legs to the main platform well above the waves, but that expense, inconvenience of access, and greatly reduced mobility is apparently undesirable.

Comment A tsunami in deep water is a non-event. (Score 2) 332

Off-shore in deep water, there is absolutely no danger whatsoever from a tsunami. A tsunami is only a problem as it reaches shore, as it's there that the very long period waves just keep coming and coming and piling up water. In deep water, there's just a very, very long swell of minuscule amplitude.

Storm waves are vastly more significant. Their period is short enough and their amplitude great enough to potentially cause significant damage to oceangoing vessels. Considering also the occasional rogue wave (a wave or short set of waves at several times the amplitude of the prevailing wave conditions at the time), and having lifeboat/evacuation drills every so often would be best practice. At least the area in question is outside the hurricane belt, so hurricane evacuations (such as those from Gulf of Mexico oil rigs) shouldn't be required.

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