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Comment Re:Wavelength is the problem for higher frequencie (Score 2) 67

by bjorniac (#60296650) Attached to: Scientists Say You Can Cancel the Noise But Keep Your Window Open

I don't know how you've ended up with that!

Velocity = Frequency * Wavelength.

Speed of sound is about 340 m/s in air at one atmosphere.

Hence wavelength = 340/20,000 = about 0.017m, (17mm).

My suspicion is that you've used the speed of light instead of the speed of sound here...

Submission + - Patrick Stewart to Return as Jean-Luc Picard 1

Submitted by Robotron23
Robotron23 writes: Veteran actor Patrick Stewart has announced he will return in a new television series exploring the later years of Jean-Luc Picard. Stewart's decision was influenced by feedback over the years from fans, as well as current events: "Jean-Luc inspired so many to follow in his footsteps, pursuing science, exploration and leadership. I feel I’m ready to return to what comforting and reforming light he might shine on these often very dark times."

Comment Zooniverse (Score 4, Informative) 105

by bjorniac (#56570688) Attached to: Ask Slashdot: Do Citizen Science Platforms Exist?

Check out Zooniverse - https://www.zooniverse.org/ - there's a lot of projects that are helped by citizen science. A nice platform where human powered processing can contribute. I don't think there's the kind of review etc you're asking for, but it does have a very nice interface for building your own project, contributing to others etc.

Submission + - SPAM: Through the Big Bang

Submitted by Anonymous Coward
An anonymous reader writes: A group of physicists have shown the Einstein's equations predict a universe before the big bang. Before this point the universe was mirrored "Our equations predict that the Big Bang was simply the moment where the orientation of space changed." No notes are given as to whether the authors have goatees in either universe.

The original paper referenced is open access in Physics Letters B.

Submission + - US Navy Under Fire In Mass Software Piracy Lawsuit (torrentfreak.com)

Submitted by Anonymous Coward
An anonymous reader writes: In 2011 and 2012, the U.S. Navy began using BS Contact Geo, a 3D virtual reality application developed by German company Bitmanagement. The Navy reportedly agreed to purchase licenses for use on 38 computers, but things began to escalate. While Bitmanagement was hopeful that it could sell additional licenses to the Navy, the software vendor soon discovered the U.S. Government had already installed it on 100,000 computers without extra compensation. In a Federal Claims Court complaint filed by Bitmanagement two years ago, that figure later increased to hundreds of thousands of computers. Because of the alleged infringement, Bitmanagement demanded damages totaling hundreds of millions of dollars. In the months that followed both parties conducted discovery and a few days ago the software company filed a motion for partial summary judgment, asking the court to rule that the U.S. Government is liable for copyright infringement. According to the software company, it’s clear that the U.S. Government crossed a line. In its defense, the U.S. Government had argued that it bought concurrent-use licenses, which permitted the software to be installed across the Navy network. However, Bitmanagement argues that it is impossible as the reseller that sold the software was only authorized to sell PC licenses. In addition, the software company points out that the word “concurrent” doesn’t appear in the contracts, nor was there any mention of mass installations. The full motion brings up a wide range of other arguments as well which, according to Bitmanagement, make it clear that the U.S. Government is liable for copyright infringement.

Submission + - University of Arizona Tracks Student ID Card Swipes To Detect Who Might Drop Out (theverge.com)

Submitted by Anonymous Coward
An anonymous reader writes: The University of Arizona is tracking freshman students’ ID card swipes to anticipate which students are more likely to drop out. University researchers hope to use the data to lower dropout rates. (Dropping out refers to those who have left higher-education entirely and those who transfer to other colleges.) The card data tells researchers how frequently a student has entered a residence hall, library, and the student recreation center, which includes a salon, convenience store, mail room, and movie theater. The cards are also used for buying vending machine snacks and more, putting the total number of locations near 700. There’s a sensor embedded in the CatCard student IDs, which are given to every student attending the university. Researchers have gathered freshman data over a three-year time frame so far, and they found that their predictions for who is more likely to drop out are 73 percent accurate. They also have plans to give academic advisers an online dashboard to look at student data in real time.

Comment Re:Core samples (Score 4, Informative) 83

by bjorniac (#55913829) Attached to: Ice Cliffs Spotted On Mars

A single shot device like a railgun cannot launch something into orbit. You need a second impulse to alter the trajectory to achieve orbit. The reason is that orbits close - they're ellipses (or circles). So with a single shot device you either launch something to infinity, or you have it crash back into the planet as its orbit intersects the point of origin.

What you'd need in this scenario is either something to collect the sample already in low orbit, or a container with a thruster of some sort to force the trajectory into orbit. Either case increases the difficulty considerably.

Submission + - Is this the expected "Bitcoin Crash"?

Submitted by bbsguru
bbsguru writes: Many financial observers are pointing to the acute decline in Bitcoin valuations this week as the start of the long-expected 'crash'. The UK Daily Express does acknowledge that, even with the current 30% decline, prices are still up 1300% over the year. Then again, how would that matter to the folks recently reported using home equity to buy bitcoin?
Some are even predicting that this will trigger a general financial crisis.

Nah. I've got all my big money safely in a floral investment. Anybody wanna buy a tulip?

Comment The Tail of a Comet (Score 1) 170

The wake behind a ball is NOT like the tail of a comet - the tail of a comet points (approximately*) away from the sun, not opposite to the direction of motion.

Comet tails are not caused by some kind of drag - the comet moves in a vacuum in (almost**) geodesic motion around the host star.

* Yes, there are actually two tails, dust and gas, directly not exactly away from the sun. The point is really that comet tails do not follow comets around the sun.

** M_comet/M_sun is normally pretty small, etc.
Government

CIA, FBI Launch Manhunt For WikiLeaks Source (cbsnews.com) 199

Posted by EditorDavid from the looking-for-leakers dept.
An anonymous reader quotes CBS: CBS News has learned that a manhunt is underway for a traitor inside the Central Intelligence Agency. The CIA and FBI are conducting a joint investigation into one of the worst security breaches in CIA history, which exposed thousands of top-secret documents that described CIA tools used to penetrate smartphones, smart televisions and computer systems. Sources familiar with the investigation say it is looking for an insider -- either a CIA employee or contractor -- who had physical access to the material... Much of the material was classified and stored in a highly secure section of the intelligence agency, but sources say hundreds of people would have had access to the material. Investigators are going through those names.
Homeland security expert Michael Greenberger told one CBS station that "My best guest is that when this is all said and done we're going to find out that this was done by a contractor, not by an employee of the CIA."

Submission + - Enceladus just became a top candidate for life elsewhere in Solar System (sciencemag.org)

Submitted by sciencehabit
sciencehabit writes: In 2005, NASA’s Cassini spacecraft spied jets of water ice and vapor erupting into space from fissures on Enceladus, evidence of a salty ocean beneath the saturnian moon’s placid icy surface. Now, it turns out that the jets contain hydrogen gas, a sign of ongoing reactions on the floor of that alien sea. Because such chemistry provides energy for microbial life on Earth, the discovery makes Enceladus the top candidate for hosting life elsewhere in the solar system—besting even Jupiter’s Europa, another icy moon with an ocean. “We didn’t see microbes,” says Hunter Waite, a planetary scientist at the Southwest Research Institute in San Antonio, Texas, and the lead author of a study published this week in Science. “But we saw their food.”

Comment Re:Fastest in what way? (Score 1) 183

by bjorniac (#52549541) Attached to: The Flux Capacitor Becomes World's Fastest Street-Legal Electric Car

Physics 101 baby ;-)

Drag racing is normally quite a good intro topic for 1D kinematics - you can do constant acceleration, look at the real relations between velocity, acceleration and position etc. It's nice because you can push the students to understand when equations are and are not valid, and what they can actually work out with limited information.

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