Splice1138

Splice1138 t1_je22ast wrote

Reply to comment by remorsefulDownfall in ELI5 How do scientists know probes (Like Voyager I) aren't going to get swept up in the orbit of another celestial body? by remorsefulDownfall

For the planets, absolutely. The Voyager probes actually relied on planetary flybys to get a "gravity assist" to slingshot them out of the solar system. Lots of calculations involved to make that happen right.

Beyond that though, colliding with a random comet or asteroid is a) insanely improbable and b) impossible to account for if you don't know about them in the first place.

As for a running into another star system, it will take about 40,000 years for either Voyager probe to come within a couple light years of another star (but we do know which those will be)

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Splice1138 t1_j7n8hfi wrote

Reply to comment by Couldbehuman in TIL the first Blue LED wasn't commercially available until 1989 and bright blue LEDs weren't available until 1993. by j-merc23

The page I read it on might have been simplifying things, not saying that's exactly how it's implemented. I do know if you play around with subsampling RGB chanels via Photoshop, for example, blue is the least noticeable, red somewhat, green very noticeable.

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Splice1138 t1_j7m56uj wrote

Reply to comment by TrumpterOFyvie in TIL the first Blue LED wasn't commercially available until 1989 and bright blue LEDs weren't available until 1993. by j-merc23

You might be a more extreme case, but human eyes can't focus on blue light as well, period. I know this first hand (and second, and third) from calibrating three tube RGB projectors back before LCD/DLP.

I also read about it being used in image compression. If you split an image into R, G, and B channels, you can save the B at half resolution and the difference is nearly imperceptible to human eyes, whereas it is easily seen if you do that with R or G.

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