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Comment by sbierwagen | Hacker News Reader

>Now it is commonplace: sit outside for a few minutes after dark, and you can’t miss them.

As always, this is only the case immediately after sunset, when it's dark on the ground but the satellites are still in direct sunlight. Fifteen minutes later they're completely invisible.

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This is a key misconception. Their SOP is to put the newest batch into an ultra-low orbit for testing. Any that fail should passively deorbit in a few months due to the increased atmospheric density. To minimize drag during this process, they deploy the solar panels parallel to the ground. Once testing is over, the panels reorient to hide behind the darkened satellite body, and then the satellites use their internal ion thrusters to boost to their final operational orbit. The dawn and dusk flaring people see are these early satellites with horizontal reflective solar panels.

There are reports of people near the poles seeing flares that are, in theory, caused by the vertically oriented panels reflecting the sun from the other side of the earth.

Scott Manley - https://youtu.be/P1TsOYcvq9A?si=7yuF2KbQFySDgG31&t=1111

Semi unrelated-

I really wonder what uncontacted tribes think of this.

The cutoff is nowhere near that soon after sunset. At midnight? Sure, you're not going to see satellites. But against a dark sky, you can see satellites reflecting for at least a couple hours. They may not be in direct sunlight as it gets later, but they are still illuminated by the atmosphere on the sunny side for a while.

Not low earth orbit satellites. As the name implies, those are flying low enough that they’re only briefly visible after sunset.

The human eye might not, but they show up just fine in astrophotography, amateur or professional, all night long.

https://james.darpinian.com/satellites/

> Fifteen minutes later they're completely invisible.

That part of the article is just intro fluff - not the problem described in the article

The school children p1ss in the public swimming pool while the adult lanes are still open ... but only during their 1 hour lesson on Monday afternoon. After that, it's totally fine.

It is fine though? Swimming pools use a complex chemical and physical filtration system.

every space sci-fi in the world presupposes that we'll do the same once our orbital lanes are packed densely.

Adults blame kids for everything. Google it and you'll think twice about swimming in a pool again :-D

Gave it up long ago!

Light pollution doesn't linger and spread over time. Once it stops being emitted, it's gone one second later.

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