A Conversation for Absorption and Emission Lines
When first switched on
AgProv2 Started conversation Feb 23, 2007
in the evening, what explains the muted purple colour of street lighting, which persists (fading out gradually) for four or five minutes as the bulb warms up to yellow/orange? Is a different agency at work here? I was surprised as a kid to notice the streetlights didn't go straight to orange - they had to warm up from magenta/purple first.
When first switched on
Traveller in Time Reporting Bugs -o-o- Broken the chain of Pliny -o-o- Hired Posted Dec 30, 2007
Traveller in Time 
playing with lights
"Exactly as you suggest, it is warming up. The Sodium needs to be evaporated before it can be used as ionised gas. During the preheating the lights show a reddish orange colour, not unlike an oven. "
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When first switched on
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