2013-04-20
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2012-11-22
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Memphet’ran on spacebattles.com, as featured by Sarah Pavis, guest editing kottke.org.
I’d heard of Orion, but not nuclear salt water rockets, which get impressive performance:
One design would generate 13 meganewtons of thrust at 66 km/s exhaust velocity (compared to ~4.5 km/s exhaust velocity for the best chemical rockets of today). Another design would achieve much higher exhaust velocities (4,700 km/s) and use 2,700 tonnes of highly enriched Uranium salts in water to propel a 300 tonne spacecraft up to 3.6% of the speed of light.
Of course, there are slight drawbacks to using these things in a biosphere:
a NSWR would eject massive quantities of superheated steam, still containing fissioning nuclear salts. Terrestrial testing might be subject to reasonable objections; as one physicist wrote, “Writing the environmental impact statement for such tests […] might present an interesting problem …”
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.
