Daily Archives: August 6, 2014

NASA technology (102)

Next-Generation Microshutter Array Technology

NASA – NASA technologists have hurdled a number of significant challenges in their quest to improve a revolutionary observing technology originally created for the James Webb Space Telescope. This image shows a close-up view of the next-generation microshutter arrays — designed to accommodate the needs of future observatories — during the fabrication process.

Determined to make the Webb telescope’s microshutter technology more broadly available, a team of technologists at NASA’s Goddard Space Flight Center spent the past four years experimenting with techniques to advance this capability. One of the first things the team did was eliminate the magnet that sweeps over the shutter arrays to activate them, replacing it with electrostatic actuation. Just as significant is the voltage needed to actuate the arrays. By last year, the team had achieved a major milestone by activating the shutters with just 30 volts. The team used atomic layer deposition, a state-of-the-art fabrication technology, to fully insulate the tiny space between the electrodes to eliminate potential electrical crosstalk that could interfere with the arrays’ operation. They also applied a very thin anti-stiction coating to prevent the shutters from sticking when opened.

> Revolutionary Microshutter Technology Hurdles Significant Challenges

Image Credit: NASA/Bill Hrybyk

Bad Politics Is Funded by Nincompoops

By Jonathan Bernstein – People are dopes.

Hey, folks: I’m all for giving money to candidates and parties. But every time you respond to ridiculous scare pitches, you make politics a little bit worse. And, yeah, I can just hear you complaining about how politics and politicians are so awful and all the rest of it. Forget that: It’s you. You’re the problem. Cut it out. more> http://tinyurl.com/kpgbgku


Why Your Willpower Can’t Stop You From Putting Things Off

By Drake Baer – Willpower is a muscle.

You know that grumpy feeling you get after a long day? That happens because we’re making hundreds of micro-decisions every day, and every decision we make takes mental effort–which, neuroscientists will remind us, is also physical effort.

So in the same way that you can only physically run so many miles in a day, your brain can only run through so many decisions in a day. more> http://tinyurl.com/nemcqav

Postcards from the photosynthetic edge

By Lynn Yarris – Photo-oxidation of water by photosystem II is responsible for most of the oxygen in Earth’s atmosphere.

At the core of photosystem II is a manganese-calcium (Mn4Ca) metalloenzyme complex that when energized by solar photons catalyzes a four photon-step cycle of oxidation states (S0-to-S3) that ultimately yields molecular oxygen. Scientists need to observe intact x-ray crystallography of the Mn4Ca ion in action but the molecule is highly sensitive to radiation.

The LCLS (Linac Coherent Light Source) is the world’s only source of x-rays capable of providing femtosecond pulses at the high intensities that allow intact photosystem II crystals to be imaged before they are destroyed by exposure to the x-ray beams. more> http://tinyurl.com/nlxrcf8

Watching the Eclipse

By David Remnick – An ideology, a world view, was taking shape: Putin was now putting Russia at the center of an anti-Western, socially conservative axis—Russia as a bulwark against a menacing America.

“Of course, this is a conservative position,” he said in a speech last year, “but, speaking in the words of Nikolai Berdyayev, the point of conservatism is not that it prevents movement forward and upward but that it prevents movement backward and downward, into chaotic darkness and a return to a primitive state.” more> http://tinyurl.com/qd3khcf