2012-05-11
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The Lunar Ranging Retroreflector, as placed on the Moon by Apollo 15:
The Laser Ranging Retroreflector experiment has produced many important measurements. These include an improved knowledge of the Moon’s orbit and the rate at which the Moon is receding from Earth (currently 3.8 centimeters per year) and of variations in the rotation of the Moon. These variations in rotation are related to the distribution of mass inside the Moon and imply the existence of a small core, with a radius of less than 350 kilometers.
2012-04-25
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NASA channeling David Hockney, via Ethel Baraona.
I hadn’t thought about the connection between Hockney’s “joiners” and NASA composites before, so seeing it brought up made me wonder. It turns out the artist’s first works using that medium were around 1970, so a few years after the Surveyor images seen here. The majority of works in the composites section of his site date from around 1982, well after the first round of planetary surveys.
Nonetheless, it’s an interesting topic to muse on.
2012-04-10
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An advert for the Burroughs 205 Computer, designed by Campbell-Ewald Company, posted to Flickr by bustbright.
2012-03-26
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Oscar Hermitte: Urban Stargazing (via):
The Urban Stargazing project focuses on bringing back the stars in the city sky by recreating existing constellations and adding new ones, narrating old and contemporary myths about London. Twelve groups of stars have been installed at different locations in the city, and can only be observed by the naked eye at night time.
Or: if you go to certain open spaces in London, and stand in the right spot, you can see new, special “constellations” that don’t exist anywhere else, designed for the city sky (as pictured above, and it’s worth enlarging the images).
Each constellation is a triangulated struture made out of clear ø 0.6mm nylon line, ø 0.2mm polyethylene braid, ø 0.75mm fibre optic and a solar powered LED. During the day, the battery is being recharged by the solar panel and the circuit switches ON the LED when it is dark enough to observe stars.
In order to have the constellation in the air, the team uses a telescopic catapult to fix the structure on top of trees.
It’s well worth reading the pages on this one, so you get the idea.
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)
