Re: How about that! 99% of the world’s popula tion in sunlight simultaneously?

On 7/8/2022 6:14 AM, a425couple wrote:
> Go to
> https://earthsky.org/earth/99-percent-worlds-population-receive-sunlight/
> 
> and view the graphic
> 
> July 8 … 99% of the world’s population in sunlight simultaneously?
> Posted by
> EarthSky Voices
> 
> July 6, 2022
> World's population: Flat map of Earth showing light areas where daylight 
> shines and dark along the bottom 2 edges.

from the comments by readers

Murf. • 17 hours ago •★★★★★
★★★★★
Wouldn't the same effect occur 17 days prior to the summer solstice?

Stephen Meier  Murf. • 16 hours ago
Astute.

Deborah Byrd Mod  Stephen Meier • 4 hours ago
Yes, that was a good question by Murf.!

Ben Weaver  Murf. • 15 hours ago
No. Seventeen days before the solstice, both sunrise and sunset occur 
later in the day. During summer (for the northern hemisphere) Earth is 
farther away from the sun than during winter. So it orbits the sun more 
slowly, and thus takes less time to rotate around the distance the earth 
covered in its orbit since the previous day. The latest sunset occurs 
around June 9th, and the earliest around December 9th. This is why 
summer is 3 days longer than winter (August v February), why you get 
later sunsets overall in winter than fall, and why you get earlier 
sunsets overall in summer than spring.

Deborah Byrd Mod  Ben Weaver • 4 hours ago
Hi Ben, I'm impressed that you're thinking about this so deeply! A 
couple of tweaks ...Yes, the earliest sunsets of the year happen before 
the winter solstice. But this isn't a true statement: "Seventeen days 
before the [summer] solstice, both sunrise and sunset occur later in the 
day." The sequence around the summer solstice is always earliest sunrise 
(before the solstice), longest day (on the solstice), latest sunset 
(after the solstice). The sequence around the winter solstice is always 
earliest sunset (before the solstice), shortest day (on the solstice), 
earliest sunrise (after the solstice). The exact date of earliest 
sunrise and latest sunset varies with latitude ... so it's not 17 days 
for everyone.