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People in cities can’t see stars anymore, so this complaint about the new satellite constellation is almost academic. In decades past, people began to be conce

People in cities can’t see stars anymore, so this complaint about the new satellite constellation is almost academic. In decades past, people began to be concerned about light pollution. The city of Phoenix, Arizona passed its first lighting ordinances around 1983. One of the goals was to reduce sky glow. After all those politicians retired LED lighting came out. Because the politicians who worked on the sky glow problem were two generations back, the current politicians didn’t realize there are very good reasons for using amber low pressure sodium bulbs for the street lights, and replaced those lights with white LEDs. The quality of light from the LEDs is terrible, but the city saves a few pennies a year (electricity, maintenance), so they probably won’t be fixing the problem. My friend told me of how she takes her grandkids out to look at the phases of the moon, and how sometimes they find a single star in the sky.

HeWhoLurksLate 7y ago
I live near a highway- at night, the sky is often gray with light pollution- and we can still see stars through it all, though it's nowhere near as amazing as what the sky looks like when you go camping. I honestly like the LED's more for driving at night- their wider spread drastically increases visibility, and if the lower cost of them means that more of them go into poorer neighborhoods, than switching to slightly more light-polluting LED's could actually be a very good thing.
- teslabox 7y ago
  There are 'okay' LED streetlights and there are 'bad' LED streetlights. Most of Phoenix's new streetlights are three LEDs pointed down. It seems like some of these use ~5000K leds (daylight / blue-white), while the others use ~2700K (much closer to incandescent). Some of the 2700K-ish streetlights lights I've looked at recently have different power output - a dimmer one was 'okay', the others were uncomfortable to be in the vicinity of. All of Phoenix's new lights have no diffusion effect - they just have three LED chips pointed down. I commented on a recent submission about the invention of the frosted light bulb [0], which were more popular than the previous bulbs because it diffused the light generated by the filament. Another LED streetlight model I've noticed (not in Phoenix) has a much more diffuse effect, because it has dozens of LEDs poined in different directions. That intersection, while inferior to the previous amber LPS bulbs, wasn't an active hazard, just mildly annoying. Flagstaff, Arizona has some amber LED streetlights. They're too intense (too bright), but they're not painful to be in the presence of, as long as I don't look directly at the amber LEDs. [0] https://news.ycombinator.com/item?id=19474110 https://news.ycombinator.com/item?id=19474110
ColinWright 7y ago
> People in cities can’t see stars anymore, so this complaint about the new satellite constellation is almost academic. There are designated areas of dark skies, and around observatories there are limits as to the lighting that can be used around. But all that is being rendered irrelevant - there are no areas that won't be affected by these satellites - that's the whole point, they will cover pretty much everywhere. And these are professional astronomers saying that they are affected. The fact that you, and others, don't really care and aren't affected isn't the point. There's a very real risk that these satellites will kill Earth-based professional astronomy, and large scale space astronomy isn't cost-effective.
- teslabox 7y ago
  The point of my post was supposed to be that people who care about earth-based astronomy really need to resist the proliferation of white led streetlights. Kids who grow up without ever seeing stars aren’t likely to care about the night sky.
  - stcredzero 7y ago
    Neil DeGrasse Tyson has a story about going to a planetarium as a child and seeing a realistic depiction of what the night sky looks like in the countryside. His immediate reaction: Fake!

HeWhoLurksLate 7y ago

I live near a highway- at night, the sky is often gray with light pollution- and we can still see stars through it all, though it's nowhere near as amazing as what the sky looks like when you go camping. I honestly like the LED's more for driving at night- their wider spread drastically increases visibility, and if the lower cost of them means that more of them go into poorer neighborhoods, than switching to slightly more light-polluting LED's could actually be a very good thing.

teslabox 7y ago
There are 'okay' LED streetlights and there are 'bad' LED streetlights. Most of Phoenix's new streetlights are three LEDs pointed down. It seems like some of these use ~5000K leds (daylight / blue-white), while the others use ~2700K (much closer to incandescent). Some of the 2700K-ish streetlights lights I've looked at recently have different power output - a dimmer one was 'okay', the others were uncomfortable to be in the vicinity of. All of Phoenix's new lights have no diffusion effect - they just have three LED chips pointed down. I commented on a recent submission about the invention of the frosted light bulb [0], which were more popular than the previous bulbs because it diffused the light generated by the filament. Another LED streetlight model I've noticed (not in Phoenix) has a much more diffuse effect, because it has dozens of LEDs poined in different directions. That intersection, while inferior to the previous amber LPS bulbs, wasn't an active hazard, just mildly annoying. Flagstaff, Arizona has some amber LED streetlights. They're too intense (too bright), but they're not painful to be in the presence of, as long as I don't look directly at the amber LEDs. [0] https://news.ycombinator.com/item?id=19474110 https://news.ycombinator.com/item?id=19474110

ColinWright 7y ago

> People in cities can’t see stars anymore, so this complaint about the new satellite constellation is almost academic. There are designated areas of dark skies, and around observatories there are limits as to the lighting that can be used around. But all that is being rendered irrelevant - there are no areas that won't be affected by these satellites - that's the whole point, they will cover pretty much everywhere. And these are professional astronomers saying that they are affected. The fact that you, and others, don't really care and aren't affected isn't the point. There's a very real risk that these satellites will kill Earth-based professional astronomy, and large scale space astronomy isn't cost-effective.

teslabox 7y ago
The point of my post was supposed to be that people who care about earth-based astronomy really need to resist the proliferation of white led streetlights. Kids who grow up without ever seeing stars aren’t likely to care about the night sky.
- stcredzero 7y ago
  Neil DeGrasse Tyson has a story about going to a planetarium as a child and seeing a realistic depiction of what the night sky looks like in the countryside. His immediate reaction: Fake!