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A moonlit tribute to a moon landing icon (blog.google)
122 points by ChrisArchitect 38 days ago | hide | past | web | favorite | 26 comments

I'd read about her daughter's fault-finding skills before, and the same bug _was_ triggered by astronauts, on "the very next flight, Apollo 8..." And _then_ the safeguard got added before Apollo 11.

* https://wehackthemoon.com/people/margaret-hamilton-her-daugh...

It turns out that children are inherently well qualified for the job of chaos monkeys.

I wonder how much the ”everyone knows not to do that” attitude to safeguards has cost in total, in money and/or human lifes.

No mention of Saydean Zeldin, her partner in the Apollo effort and Higher Order Systems?

(I met both of them a long time ago, in my proof of correctness days.)

It's an article focused on Hamilton; seems to be part of a series of articles for an Apollo 11 anniversary feature: https://artsandculture.google.com/project/moon-landing

Good point, I'd seen the Margret Hamilton image quite a few times since it started circulating but nothing of Saydean Zedlin. I was glad to learn about her thanks to your comment


For those of you only interested in what 107K mirrors are doing in the desert, it's the Ivanpah Solar Facility. The mirrors bounce sunlight onto solar receivers in the towers. http://www.brightsourceenergy.com/ivanpah-solar-project

Thank you I was wondering if they would set all of these mirrors up just for this event.

I used to drive past this facility often. The towers are shockingly bright from the highway. Never thought about using the mirrors for an art installation, really cool idea!

I wonder how Google convinced Tonopah to be onboard.

That's the Ivanpah facility south of Las Vegas, not the ones in Tonapah.

Oops, you're right! That's the one I was thinking of, just got the names reversed.

Google is an investor in the Ivanpah project

Dang, I was hoping the blog would go into a little bit about how they accomplished this! Either way though, insanely cool tribute.

Agree! It looks great — I assume they did it pretty much how DMD (Digital Mirror Device) chips in DLP projectors work. The mirrors already have a mechanism to track sun (mentioned in the article), and adjust the direction its reflection should point. they could activate tracking partially to create the image.

I agree! There must be some sort of program written that allows them to put any image on their solar display :)

Not related to the Article really, but in those photos there seem to be fires at the base of the Ivanpah solar collector towers... what's going on there?

Same tangential relation: Ivanpah is amazing. Note that the tribute mirrors are just 1/3 of the total installation.

Had a partial tour of it a few years ago, before they accidentally focused the mirrors below the steam boxes and destroyed the towers. They rebuilt with molten salt so they can supply the generators at night.

Not fires--seems to be the lights from the buildings surrounding the towers.

Just looks like high pressure sodium lights to me.

Thank you. That makes sense. I appreciate the answer. I camp outside that area sometime -- I'll try to get a good look with my binoculars the next time I'm there.

Note that they _do_ heat the plant with natural gas overnight, so there is a huge fire in there somewhere.

Oh really? Why? Is it to keep things at a nominal operating temperature in prep for the next day, or is it to continue generating electricity once the sun has gone down (or other reason)?

>Gas is burned at night to keep the system primed and to heat water used in the tower boilers. This allows electricity production to start up more quickly when the sun comes up each morning, plant operators said. Gas also is burned during periods of intermittent cloud cover.


The steam cycle has to be up and running before sunrise so they can meet their generating obligations, so they have to ramp up with natural gas while it is still dark. The facility is also capable of operating as a dispatchable "peaker" power plant.

There's a huge amount of right-wing disinformation about solar power so if you just Google for "Ivanpah natural gas" you'll get an outpouring of stupid blogs, but reading them will get you close to the truth.

I noticed that the stack of folders almost exactly matches her height! Amazing work!

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