Space & astronomy · the experiment
Defend Rubin's twilight
A million satellites carrying computers, glints brighter than the stars, a twilight sky lighting up. Four questions, from beginner to expert, to measure what Rubin would lose.
1 · Spot the worst orbits
Beginner
Why do Sun-synchronous satellites do disproportionate damage?
2 · Compare a glint with the limit
On the magnitude scale, each magnitude lower makes an object 2.512 times brighter.
Intermediate
A glint off a panel reaches magnitude 2. Compared with the International Astronomical Union's limit, magnitude 7, it is:
3 · Measure the twilight
In moonless twilight, the satellites add more than 1,000% of the natural sky glow in three filters.
Expert
How many times brighter than the natural sky is the sky then, at least?
4 · Judge the remedy
With a tenth of the satellites, twilight images lose 2.33% of their pixels per night, against 6.88% with the full fleet.
Expert
Why is the loss not divided by ten?
Twilight defended
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