GeekSpeak for 2008-05-10

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Ben’s sweet infatuation with Earth, Paris privacy issues, the BBC hates knitters, to sonic-boom or not to sonic-boom, and other geek news items.

Also this episode the Geeks ask a lot of questions. “We just don’t know that much.”

Gogle Street View vs. French privacy laws

Google has begun scanning the streets of Paris, gathering data for its Street View service, which adds street-level photography to the satellite views offered by Google Maps. The search company will gather a wealth of data from the project but, thanks to France’s strict privacy laws, it may also pick up a few lawsuits on the way if it chooses to publish the photos unedited. …

Who's Knitting Copyright

A knitter is getting threats from the BBC to take down his knitting patterns for Dr Who.

NASA to remove the "boom" from sonic booms

NASA and the Japan Aerospace Exploration Agency (JAXA) this week announced a partnership to jointly research sonic boom. NASA said sonic boom modeling is one of the key technologies needed to let a next generation supersonic aircraft quiet enough that it can fly supersonically over land without significant disturbance to the people or damage to property under such noise.

The change in air pressure associated with a sonic boom is only a few pounds per square foot — about the same pressure change experienced riding an elevator down two or three floors. It is the rate of change, the sudden onset of the pressure change, that makes the sonic boom audible, NASA said. All aircraft generate two cones, at the nose and at the tail. They are usually of similar strength and the time interval between the two as they reach the ground is primarily dependent on the size of the aircraft and its altitude. Most people on the ground cannot distinguish between the two and they are usually heard as a single sonic boom. Sonic booms created by vehicles the size and mass of the space shuttle are very distinguishable and two distinct booms are easily heard. …

India, Belgium warn of Chinese attacks (off air)

Add India and Belgium to the list of countries worried about attacks coming from China.

Officials from both countries warned the public over the past week that online attacks — appearing to come from the People’s Republic of China (PRC) — have targeted their government networks. Unnamed Indian officials told the Times of India that almost daily probes have focused on mapping and scanning India’s official networks over the past 18 months. The Justice Minister of Belgium warned that e-mail attacks, aimed at compromising government computers, appear to be coming from China, according to a United Press International report.

The Earth is a Giant Piece of Candy

The inside of the Earth is not as simple as previously believed. (I love chocolate, peanut butter, and honey). Yum….

Platypuses are Strange, Down to Their DNA

Scientists have mapped the genetic makeup of the duck-billed platypus — one of nature’s strangest-looking animals with the beak of a duck, the fur of a mammal and the venom of a snake.

TiddlyWiki

“TiddlyWiki is a complete wiki in a single HTML file. It contains the entire text of the wiki, and all the JavaScript, CSS and HTML goodness to be able to display it, and let you edit it or search it. Without needing a server.”

There are several different variants of TiddlyWiki. They can be found via a Google search. I personally use the one linked above.

VW getting thrifty with fuel

VW has announced the 1L concept car, a 238 mpg fuel sipper, will go into production in 2010. Also, VW will release 2009 [Jetta TDI Diesel|http://blog.wired.com/cars/2008/04/coming-soon-to.html], which is expected to get 60 mpg, while being incredibly low on emissions.

Birds can actually see magnetic fields

Cryptochromes in bird eyes give them “quantum magno vision” to see magnetic fields.


! Feed Back from Listeners

We did ask a few questions this episode, and we got some great feed back, thanks everyone.

!! Patricia wrote:

!! Don wrote:
Did you know that the SB can be visible? http://www.flickr.com/photos/doneastwest/163100543/

…and about the Earth’s core:

!! Elisabeth wrote:
A person who knits is a knitter. If they create other things with wool or fiber they could be a felter or fiber artist.

Thanks for geek speak!

! Sonic Boom

!! Marcus wrote:
The sonic boom occurs any time that the aircraft is traveling supersonic. It is a cone surrounding the aircraft with the point just in front of the
nose. As the aircraft travels faster, the cone becomes steeper (a sharper
point). It is basically the pressure wave caused by the aircraft pushing
the air out of its way, but since the aircraft is going faster than the
speed that the air can move at, the pressure wave piles up on itself. This is similar to the wake of a boat, caused by the boat pushing the
water out of its way, but the boat is traveling faster than the wave
itself.

Anyhow, when the cone surrounding the airplane reaches the ground, an
observer experiences a “double boom” as the cone passes over them. The
first boom is a positive overpressure, then the pressure drops off and
becomes negative, then the second boom is a sharp return to the normal
atmospheric pressure. A graph of the sound pressure vs time looks line an
“N” with the first leg of the N being the rise in pressure, then the
fall-off to negative, and finally a sharp rise back to ambient pressure.

Incidentally, the photo on flickr isn’t a sonic boom itself, but it is an
interaction of the shock waves around the airplane (the cone surrounding
it) with the moisture in the air. After the overpressure, during the
second half of the N, the pressure is below ambient and if the humidity
level is just right, the moisture condenses into a cloud.

! Joe on the Forums
Joe wrote some [more great information about topics covered in this episode|http://forums.geekspeak.org/viewtopic.php?f=12&t=42] on our forum.