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Astronomers Solve the Mystery of 'Hanny's Voorwerp' 123

Posted by kdawson
from the do-not-look-directly-into-the-quasar dept.
KentuckyFC writes "In 2007, a Dutch school teacher named Hanny van Arkel discovered a huge blob of green-glowing gas while combing though images to classify galaxies. Hanny's Voorwerp (meaning Hanny's object in Dutch) is astounding because astronomers have never seen anything like it. Although galactic in scale, it is clearly not a galaxy because it does not contain any stars. That raises an obvious question: what is causing the gas to glow? Now a new survey of the region of sky seems to have solved the problem. The Voorwerp lies close to a spiral galaxy which astronomers now say hides a massive black hole at its center. The infall of matter into the black hole generates a cone of radiation emitted in a specific direction. The great cloud of gas that is Hanny's Voorwerp just happens to be in the firing line, ionizing the gas and causing it to glow green. That lays to rest an earlier theory that the cloud was reflecting an echo of light from a short galactic flare up that occurred 10,000 years ago. It also explains why Voorwerps are so rare: these radiation cones are highly directional so only occasionally do unlucky gas clouds get caught in the crossfire."

OpenSSH 5.4 Released 127

Posted by timothy
from the but-it's-secret dept.
HipToday writes "As posted on the OpenBSD Journal, OpenSSH 5.4 has been released: 'Some highlights of this release are the disabling of protocol 1 by default, certificate authentication, a new "netcat mode," many changes on the sftp front (both client and server) and a collection of assorted bugfixes. The new release can already be found on a large number of mirrors and of course on www.openssh.com.'"

Comment: Doesn't surprise me. We use them to Teach. (Score 1) 110

by The Infamous TommyD (#30453972) Attached to: Using Hacked Wiimotes As Scientific Sensors

I've been using them in my Computer Eng. Problem Solving class for 3 years.

Here's a vid where freshmen measure a drop (accounting for air resistance) using a wiimote.
I'd say they make a great instrument as long as you quantify your error.

Comment: It's Not About the Games! (Score 1) 173

by The Infamous TommyD (#30226616) Attached to: Computer Games and Traditional CS Courses

If done right, the game or whatever just serves as an engagement and recruiting tool. The important bit is then using the platform to introduce problem solving and programming learning opportunities and then relating that back to the non-gaming IT world.

In my case, I teach the first course in Computer Engineering, and I use the Wii Controller as the data source. Check out http://www.youtube.com/watch?v=tPCBfyQP4eE to see a lab where students use the wii remote in a foam football to measure the distance it fell in real time in an 8+ meter drop.

This draws on their physics, math, and learning how to structure solutions to a problem nicely.

You don't have to know how the computer works, just how to work the computer.