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Comment Re:Which means (Score 1) 347

No particle travel faster than the speed of light in vacuum. Light travels slower in certain materials to the point it is almost completely stopped (several experiments are studying such events). Cerenkov radiation occurs when a charged particle exceeds the speed of light in a certain material (e.g. water). See:

Comment Re:Translation please? (Score 3, Informative) 168

Acutally it's the increase in the particles/sec measured by Voyager-1 in the last months compared to the lack of a similar increase in the same data for Voyager-2. V1 is further away form the Sun and the decrease in the sollar wind intensity probably translates in more GCR (galactic cosmic rays) reaching that region of space when compared to the position of V2.

Submission + - The SpaceX blast into history (

coondoggie writes: "Space Exploration Technologies or SpaceX has sent its Falcon 9 rocket and Dragon space capsule into low earth orbit on the first public resupply mission to the International Space Station. The Dragon will stay about 18 days and deliver a little over 1,000 pounds of cargo. A successful mission will go a long way toward bolstering the idea of non-NASA spacecraft ferry equipment and ultimately astronauts to the space lab. It won’t be an easy task by any means. “This is a really tough flight. What we’re asking them to do is amazing,” NASA’s William Gerstenmaier said. Here we take a look at the components of this historic event."

Submission + - Raspberry Pi USB power problems? (

rephlex writes: "There are multiple Raspberry Pi users on the official Troubleshooting forum experiencing hardware problems with their Pi. It appears the Raspberry Pi has problems with USB, specifically with powering peripherals that require 140 mA or more. That situation causes a voltage drop that results in the USB voltage becoming out of specification. This has resulted in malfunctions with USB devices such as Wi-Fi dongles, even when connected to the Pi via a powered hub. Also, there appears to be Ethernet problems caused by this "excessive" (but well within USB specifications) current draw:"

Submission + - SpaceX Falcon 9 rocket launches ( 1

MalHavoc writes: After an aborted launch attempt last week, SpaceX finally became the first commercial company to send a rocket towards the International Space Station. The Falcon 9 rocket carrying the Dragon capsule blasted off from Cape Canaveral at 3:44 a.m. EDT and if everything checks out, it will attempt to dock with the ISS on May 25th.

Submission + - University of Minnesota Launches Review Project for Open Textbooks

Durinia writes: Minnesota Public Radio is running a story today about the University of Minnesota's Open Textbooks project. The goal of the project is to solicit reviews of college-level open source textbooks and collect those that pass muster onto their website. The project will focus first on high-volume introductory classes such as those for Math and Biology, because as David Ernst, director of the project, states in the interview:

"You know the world doesn't need another $150 Algebra One book. Algebra One hasn't changed for centuries, probably."

Comment Re:know your market (Score 1) 281

For the best part of this year I've been waiting for a tablet with linux. A cross between a notebook and a tablet is the best of the two worlds. Imagine being able to run all Linux programs from your tablet. I figure there would be a decrease in the battery time, but with ARM processors you can have better power management. So count me in as a potential customer.

Comment Touch more than 4 digits. Probelm solved. (Score 1) 157

As I cover my hand to hide the numbers I always touch more than the four digits whenever I input my PIN as I center my hand on the keypad. Most of the time I also fake pressing some digits by keeping my finger onto them. I never thought of the thermal way to recover PIN numbers but I think I am safe.

Comment Re:Mistake in Article (Score 1) 287

They mention variable voltage in the next sentence so I think they assumed 900 mA at a voltage of up to 110 V (US version) and that gives 99W. I don't know it the 110 V is derived from the actual specification or it was assumed by the american author. I presum the later as a normal PC power supply provides DC current and the maximum drob between the most negative rail (-12V) and the most positive (+12V) is 24 V. You also have to take into consideration that the maximum current at -12V is in the hundreds of mA so it is safe to assume the new standard will allow voltage negotiation between 5 and 12 V. At 900 mA the maximum power is just below 11W. Which is more than 4 times larger than USB 2.0 spec.

It is easier to change the specification to fit the program than vice versa.