General Discussion

hunter

(40,531 posts)

34. I'm guessing it's the type of streetlighting.

Wed Jan 1, 2014, 04:11 PM

Jan 2014

red - low pressure sodium, lowest electric cost, occasionally installed to reduce interference with optical astronomy installations

orange - high pressure sodium.

blue - mercury vapor lighting

yellow, in less "modern" places - mix of incandescent, sodium, and mercury vapor

yelow, "modern" places - mix of high pressure sodium, metal halide, and recently, LED.

I've lived through every generation of lighting. When I was a kid the streetlights were incandescent. Later they were mercury vapor. Then our family moved to a place with low pressure sodium lighting. When we returned to the U.S. the streetlights had been replaced with high pressure sodium. Then big box store parking lots started installing "white" metal halide lighting. Our city is gradually upgrading to LED lighting but the annoying streetlight in front of our house is still the orange high pressure sodium.

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Wow! Check out this photo from space of Europe celebrating The New Year last night: [View all] Are_grits_groceries Jan 2014 OP

Sweden surprises me Cirque du So-What Jan 2014 #1

Zero daylight this time of the year there dipsydoodle Jan 2014 #6

Probably so Cirque du So-What Jan 2014 #7

Norway is quite narrow at high latitudes Thor_MN Jan 2014 #11

You're right Cirque du So-What Jan 2014 #13

Cirque du So-What Diclotican Jan 2014 #14

Thanks for the information Cirque du So-What Jan 2014 #15

Cirque du So-What Diclotican Jan 2014 #17

My ancestors Cirque du So-What Jan 2014 #19

Cirque du So-What Diclotican Jan 2014 #21

Old Mårten Mårtensson (so-called in church records for living to be 100) Cirque du So-What Jan 2014 #26

My father's side was partially Norwegian mimi85 Jan 2014 #56

This is interesting GreenEyedLefty Jan 2014 #63

This picture is kind of bullshit titaniumsalute Jan 2014 #44

Yes Cirque du So-What Jan 2014 #46

Yes and by the way titaniumsalute Jan 2014 #49

I was thinking along those same lines. Curmudgeoness Jan 2014 #51

My thoughts too. n/t jellen Jan 2014 #58

Awesome picture. Thanks for posting. k&r n/t Laelth Jan 2014 #2

What a beautiful picture! CaliforniaPeggy Jan 2014 #3

It was totally clear over all of Europe last night? Brickbat Jan 2014 #4

A friend posted that on FB today. dipsydoodle Jan 2014 #5

WOW is right! 2naSalit Jan 2014 #8

Why is Ireland red? Kablooie Jan 2014 #9

I was wondering that myself. surrealAmerican Jan 2014 #22

I'm guessing it's the type of streetlighting. hunter Jan 2014 #34

Bloodshot? George II Jan 2014 #36

Yeah, they must have started early. lpbk2713 Jan 2014 #41

That image really underscores the amount of light pollution... blackspade Jan 2014 #10

I calle my son in Glasgow last night at 12:30 their time NBachers Jan 2014 #30

Glasgow is a great city but I prefer the Highlands. blackspade Jan 2014 #37

Was wondering what those lights were. nt RedCappedBandit Jan 2014 #45

Lots of oil platforms in the North Sea. Thor_MN Jan 2014 #12

Gorgeous malaise Jan 2014 #16

This is likely photoshopped... HipChick Jan 2014 #18

Not a cloud in the sky either...highly unlikely to Lucky Luciano Jan 2014 #20

Yep...especially this time of year.. HipChick Jan 2014 #23

The lights would still be on all evening wouldn't they? treestar Jan 2014 #29

+1 iamthebandfanman Jan 2014 #61

Photoshopped or not, it always amazes me that map makers got it so right. mountain grammy Jan 2014 #24

It's really astounding, isn't it! What a photo! calimary Jan 2014 #35

Those fuckers know how to party! JaneyVee Jan 2014 #25

Part of me sees pretty colors. The other sees a human desert. ffr Jan 2014 #27

Those Belgians treestar Jan 2014 #28

Fake and fake and fake Android3.14 Jan 2014 #31

The sad thing is, the real explanation of that picture is pretty cool. nytemare Jan 2014 #32

That *is* pretty cool... TroglodyteScholar Jan 2014 #38

Is very cool. Dumb, but is that Moscow? I could check the map. anneboleyn Jan 2014 #43

ALERT: This is not from last night's New Year celebrations. Beartracks Jan 2014 #33

killjoy lol MFM008 Jan 2014 #39

lol Beartracks Jan 2014 #59

Message auto-removed Name removed Jan 2014 #40

cool. Liberal_in_LA Jan 2014 #42

cars being torched...nt quadrature Jan 2014 #47

Beautiful photo, but these night photos from space... bvar22 Jan 2014 #48

Interesting photo heaven05 Jan 2014 #50

No Russia? nt Jamaal510 Jan 2014 #52

They partied like it's 999 in North Korea Kaleva Jan 2014 #53

Oh I'm So Sorry to report that this is NOT a shot of Celebrations from Space. It's Just NOT. NYC_SKP Jan 2014 #54

Wow thats KQQL. I'd love to have pictures of the whole planet Historic NY Jan 2014 #55

Ireland is one big red light district Kaleva Jan 2014 #57

That photo is great proReality Jan 2014 #60

It looks like porno to me.... WCGreen Jan 2014 #62

This whole area is not in the same time zone. oldandhappy Jan 2014 #64