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PAGEOS Satellite (1966) (sh.itjust.works)

submitted 2 days ago by einfach_orangensaft@sh.itjust.works to c/pics@lemmy.world

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[–] QuarterSwede@lemmy.world 159 points 2 days ago* (last edited 2 days ago) (6 children)

PAGEOS had a diameter of exactly 100 feet (30.48 m), consisted of a 0.5 mils (12.7 μm) thick mylar plastic film coated with vapour deposited aluminum enclosing a volume of about 524,000 cubic feet (14,800 m3)[8][9] The metal coating both reflected sunlight and protected the satellite from damaging ultraviolet waves. The satellite was launched in a canister, which explosively separated as it was ejected from the rocket. Then, the balloon was inflated through a combination of residual internal air and a mixture of benzoic acid and anthraquinone placed inside, which turned to gas when the satellite was exposed to the heat of the sun.[9] It was the first satellite specifically launched for use in geodetic surveying,[3] or measuring the shape of the earth, by serving as a reflective and photographic tracking target. At the time, it improved on terrestrial triangulations of the globe by about an order of magnitude.[4] The satellite, which carried no instrumentation, broke up between 1975 and 1976.

Wikipedia

This was super interesting to read about. I thought the picture surely had to be CG or AI created at first.

[–] thisbenzingring@lemmy.sdf.org 34 points 2 days ago (2 children)

Over five years, 16 groups conducted observations at 45 globally distributed stations, about 3000-4000 km apart from each other.[4][7][12] 12 mobile tracking stations were used, which observed during favorable weather conditions during a few minutes of twilight each evening.[7][why?][clarification needed] BC4 cameras were used to photograph the satellite.[12] Observations were taken when the satellite was visible simultaneously to multiple stations at the same time.[12] This resulted in the fixing of the precise locations of 38 different points around the world.[4] This could be used to help determine the precise locations of the continents relative to each other, and to help determine the precise shape and size of the earth.

that is amazing! so cool

[–] XeroxCool@lemmy.world 17 points 2 days ago

And it sounds like it was usable for 9 years. That's impressive for a very thin balloon surrounded by 50,000mph dust particles

[–] DrownedRats@lemmy.world 4 points 1 day ago

That'd actually very similar to how trig points work! It's a giant orbiting trig point. Someone call the ordnance survey!

[–] bcgm3@lemmy.world 12 points 2 days ago

I thought the picture surely had to be CG or AI created at first.

Same... This photo is so surreal, I immediately thought of Simon Stalenhag.

[–] LovableSidekick@lemmy.world 9 points 2 days ago* (last edited 2 days ago)

Remember this experience when someone "knows" something is AI because It's "obvious", and don't call me Shirley!

[–] Evil_Shrubbery@lemm.ee 4 points 2 days ago

Big boyo.

Not a smart boyo tho.

[–] b3an@lemmy.world 1 points 1 day ago

At first I was like, what AI is this… Oho. Very cool!

[–] frezik@midwest.social 1 points 1 day ago

Interesting. I wonder if the canister could fit in a modern microsat. Might be possible to recreate it for (relatively) cheap.