2012-03-23
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Windswept, designed by Charles Sowers Studios, is a wind-driven kinetic facade that transforms a blank wall into an observational instrument that reveals the complex interactions between wind and environment. The design consists of 612 freely-rotating directional arrows, which serve as discrete data points indicating the direction of local flow within the larger phenomenon.
I think I’ll have to meander up the hill to have a look at this one. (Photographs: Bruce Damonte.)
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Meet CERN’s New Artist in Residence, Julius von Bismarck in Wired. (via)
Von Bismarck is the first in the Collide @ CERN programme, and will serve a two-month residency.
The article goes on to note Public Face, which “mounted a giant neon smiley above the city of Berlin; the smiley changed its expression based on an estimate of the city’s mood that day”, and Image Fulgurator, “a hacked camera that injected stealth images into other people’s photos when they weren’t looking” which “won the top prize at Ars Electronica in 2008”.
Astronomers vs Billboards
From the Arizona Republic, Bill divides electronic-billboard firms, astronomy industry (via, via):
The forces of dark are squaring off against the forces of light in a battle over billboard legislation.
On the side of light — as in vivid, flashing color — is the electronic-billboard industry. It is pushing a bill that would make 70 existing digital billboards along Arizona’s highways legal in the wake of a state Court of Appeals ruling.
The forces of darkness are led by Arizona’s observatories and astronomy industry. They want a statewide standard to ensure “dark skies” protections for areas within a 75-mile radius of observatories.
Since when was astronomy an industry? I suppose if there are enough people based there making telescopes that might be justified, but it seems like odd language. Mind you, it’s the language used in an opinion piece by Angela Cotera, a research astrophysicist at the SETI Institute in Avondale, arguing against the law. Anyway, returning to the original article:
Billboard companies approached lawmakers for a change to state law after the Appeals Court last fall ruled electronic billboards did not comply with the state’s ban on intermittent light.
Meanwhile, this seems a bit surprising:
The Discovery Channel, which is building a new telescope southeast of Flagstaff near Happy Jack, told lawmakers that the limits would help ensure dark skies. Its imaging camera “will be sensitive to even minute increases in sky glow.”
When did TV stations start building telescopes?
Despite a leader in the Republic and letters against the bill (and for dark skies), another leader posted yesterday notes
The Legislature has unaccountably passed a bill that threatens a unique and precious Arizona asset: our dark skies. Gov. Jan Brewer needs to veto it.
and goes on to say
In this intensely competitive economy, Arizona is fortunate to have a major advantage in astronomy and optics. Our clear, dark nights offer a world-class view of the universe. Arizonans count on Gov. Brewer to protect them. Gov. Brewer should push the off switch on HB 2757.
2012-03-22
On Strong Magnetic Fields
Robert Duncan, Strong Magnetic Fields:
Many fascinating physical effects occur in magnetic fields with strength exceeding the “quantum electrodynamic field strength” of BQ=4.4×1013 Gauss. (This field-strength given by a combination of fundamental constants: BQ = me2c3/he, where me is the mass of the electron, c is the speed of light, h is Planck’s constant divided by 2 π, and e is the charge on an electron.) In fields stronger than BQ, electrons gyrate at nearly the speed of light around magnetic field lines, even in their lowest quantum energy states. Consequently, the ultra-magnetized vacuum — which, according to quantum mechanics, seethes with virtual electron-positron pairs and other particles — becomes birefringent like a calcite crystal, capable of distorting and magnifying images (“magnetic lensing”). X-ray photons traveling through such strong fields readily split into two, or merge together; and many other novel physical effects come into play.
There’s more on extremely strong magnetic fields at this arxiv paper. (via science.tumblr.com’s post on magnetars)
2012-03-07
Space is closer than you might think
Space always seems so far away and much of it actually is. But space is actually quite close to where we are all sitting right now. The Kármán line, the commonly accepted boundary between the Earth’s atmosphere and space, is only 62 miles above sea level.
Or, as Fred Hoyle put it,
Space isn’t remote at all. It’s only an hour’s drive away if your car could go straight upwards.
2012-02-19
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Kristian Birkeland’s terrella, as pictured in an article about his use of the models at Sphæra, the newsletter of the Museum of the History of Science, Oxford:
Birkeland’s largest experiment was carried out in 1913 in a large vacuum chamber of 1,000 litres capacity with terrellas of 24 and 36 cm in diameter. This apparatus became very well known for its ability to recreate Aurora effects and in Norway its fame is such that it is depicted on the Norwegian 200 kroner banknote.
That banknote is one of the most attractive I’ve seen from any country. Sadly, as this excerpt of Lucy Jago’s excellent book The Northern Lights recounts, Birkeland’s theoretical explanation of the aurora, based on observational work in the far north of Norway during long, cold winters failed to convince the influential British scientific establishment:
Arthur Schuster, a Fellow of the Royal Society and a prominent scientist in the field of terrestrial magnetism, dismissed Birkeland’s huge volume with a terse comment in the Society’s Proceedings:
“Even originally well-defined pencils of cathode rays from the sun cannot reach the Earth. For Birkeland’s theories to be correct, the existence of such cathode rays is clearly presupposed to be necessary… and this assumption is untenable.” Birkeland was furious, for he knew that, if his theories were ever to be widely disseminated, it was necessary for the British scientific establishment to accept them. Over the next five years, Birkeland’s life fell apart.
It was only in the 1960s that the “cathode rays”, or what we’d now call the solar wind (a stream of charged particles, both electrons and protons) were observed and his theories about the cause of aurora were vindicated.
(inspired by Dan W’s post of a different image of a terrella)
2011-12-22
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Because nothing says Christmas like synthetic neurons automatically reconstructed from microscopy image stacks.
(via Wellcome Image of the Month: Christmas Cells « Wellcome Trust Blog)
Oh, that’s nice, that is.
2010-11-24
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2010-11-14
Above London: a retirement notice
Over three years ago, at the Yahoo/BBC Hackday in Alexandra Palace, candace and I knocked up Above London and Above SF, two Twitter bots that would alert followers in one of those two cities that the International Space Station (or an Iridium flare) would be visible.
I’m happy with the reception it got, and I still prefer its output to that of some of the subsequent services that provide the same service (such as @overlondon or @twisst). However, it was always a bit of a pain to look after (true to the word “hack” in the event title, I cut corners when it came to handling DST, and occasionally the cron jobs running it would fall over).
Two things have finally done for it: Twitter’s move to OAuth, and more importantly, the fact I managed to leave the only copy of the code on a server that’s now sitting, unplugged, in the UK. Even the service on which I posted the write-up of the hack has now closed. Given that, it’s probably best that I post a message to the Twitter accounts, and formally shut up shop (for now, at least).
Thanks to everyone who followed either the San Francisco or London account, and good luck with one of the aforementioned alternatives. I hope you got to see the ISS at least once. It’s always warmed my heart to look up and see the few humans that circle the world, shining brightly in the evening twilight.
2010-10-19
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An Exploratorium sign at the back of a parking lot between the two piers needs only a 7-foot metal “O” to be complete. Photo: Lea Suzuki.
The tugboats are moving, the dredges are working, and today Exploratorium officials will host a groundbreaking ceremony on a $300 million project that will transform two huge piers on the Embarcadero into a new home for the hands-on science museum.
