Aug. 25, 2015
Peter Merlin, Public Affairs
NASA Armstrong Flight Research Center
This schlieren image dramatically displays the shock wave of a supersonic jet flying over the Mojave Desert. Researchers used NASA-developed image processing software to remove the desert background, then combined and averaged multiple frames to produce a clear picture of the shock waves.
Credits: NASA Photo
NASA is using a 21st century version of schlieren imagery, invented by a German physicist in 1864, to visualize supersonic flow phenomena with full-scale aircraft in flight.
Credits: NASA Photo
NASA researchers in California are using a modern version of a 150-year-old German photography technique to capture images of shock waves created by supersonic airplanes. Over the past five years scientists from NASA’s Armstrong Flight Research Center at Edwards Air Force Base and Ames Research Center at Moffett Field have teamed up to demonstrate how schlieren imagery, invented in 1864 by…
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24 Aug 2015
A layer of carbon can bestow the powers of magnetism. Viviane Richter explains.
A magnetic field: Magnets have become crucially important in the computer age, so researchers are seeking to learn how to magnetise metals without the help of rare Earth elements.Credit: Science Photo Library / Getty Images
In a feat of modern day alchemy, scientists have successfully turned non-magnetic metals into magnets. Oscar Cespedes at the University of Leeds and his team published their magnetic recipe in Nature in August. The key ingredient? A dusting of carbon.
“This is a new way of making magnets – it opens up a new field!” says Naresh Dalal from Florida State University, who also researches magnetic materials.
Magnets are crucial in the age of big data. We’ve generated almost as much data in the past two years as during all of human history. To generate and…
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Noted hurricane expert Dr. Philip Klotzbach of Colorado State University has had some interesting discussion and stats on his Twitter feed, for example:
10 years ago today, TD 10’s remnants brewed north of Hispaniola. 8 days later, Katrina was a Category 5 in the Gulf.
It is worth noting that 2005 had 11 named storms, seven of which hit land and five of which caused major damage. In contrast to that era, we’ve recently seen the fourth named storm in the Atlantic, Hurricane Danny, fizzle out back to tropical storm status last Saturday, and now as a tropical depression is listed as remnant status by NHC. Given NOAA’s recent update for a below normal season, this isn’t surprising.
The remnants of…
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Discussions of the Arctic often include references to “Polar Amplification,” defined thusly by climate scientists (wikipedia):
“Polar amplification refers to the observation that any change in the net radiation balance (for example greenhouse intensification) tends to produce a larger change in temperature near the poles than the planetary average.”
NSIDC adds in the notion of positive feedbacks and concern over “tipping points.”
“Scientists have already seen evidence that positive feedbacks are occurring in the Arctic. They call this Arctic amplification. Predicting the Arctic climate is difficult. Some of the changes in the Arctic could also have negative feedback effects, or effects that reduce the amount of warming. For example, if warm temperatures make the Arctic growing season longer, more plants can survive and take up more carbon from the air. However, most evidence suggests that the positive feedback effects outweigh the negative effects. A recent report by NOAA concluded that…
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August 19, 2015
Diagram of the Lagrange points associated with the sun-Earth system
A Lagrange point is a location in space where the combined gravitational forces of two large bodies, such as Earth and the sun or Earth and the moon, equal the centrifugal force felt by a much smaller third body. The interaction of the forces creates a point of equilibrium where a spacecraft may be “parked” to make observations.
These points are named after Joseph-Louis Lagrange, an 18th-century mathematician who wrote about them in a 1772 paper concerning what he called the “three-body problem.” They are also called Lagrangian points and libration points.
Structure of Lagrange points
There are five Lagrange points around major bodies such as a planet or a star. Three of them lie along the line connecting the two large bodies. In the Earth-sun system, for example, the first point, L1…
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Judgy Bitch with a funny take on the recent ‘air conditioning is sexist’ news item [Not safe for work contains language]
Gobsmacked. I would not be surprised if the investigation gets bogged down (note the pun) for years to come so the guilty get distance. This smells and scorches more than the poisoned waters the EPA leave behind.
Well, I hadn’t written about the Colorado incident, mostly because it seemed due to incompetence and was an accident. That our federal government is full of incompetents isn’t all that noteworthy, it’s a given.
But, here’s something else that’s a given. The EPA doesn’t function to protect our environment, it functions as an arm to exert governmental control over the private citizenry.
As it turns out, there’s much more to this sordid story than just continuous incompetence from our government.
The EPA has a record of releasing toxic runoff from mines in two tiny Colorado towns that dates to 2005, a local mine owner claims.
The 3-million-gallon heavy-metal spill two weeks ago in Silverton polluted three states and touched off national outrage. But the EPA escaped public wrath in 2005 when. That dump – containing arsenic, lead and other materials – said Todd Hennis, who owns both mines along…
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[image credit: etsy.com]
Something a bit off-beat here: a paper entitled ‘The Multiperiodic Pulsating Star Y Cam A as a Musical Instrument’. A music extract can be played in the linked Phys.org report. It’s described as ‘a mixed bag of eerie pulsating sounds combined with a simple piano melody.’
Astronomer Burak Ulaş, with the Izmir Turk College Planetarium in Turkey has taken his work into a musical dimension, using star oscillations as a source for a musical composition. He has uploaded a paper describing what he has done along with sheet music and an audio recording of his work to the preprint server arXiv—along with a shout-out to other pioneers in the field, from Kepler to Pythagoras to modern composer scientists Jenő Keuler and Zoltán Kolláth.
Astronomers and other star-gazers have long associated celestial bodies with music, the twinkling of some stars offers a tempting back-beat and some stars…
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