Our BetterMost Community > The Holiday Forum
Happy Longerdays!
serious crayons:
--- Quote from: Jeff Wrangler on August 12, 2022, 01:50:38 pm ---It's the funniest thing. We've had this discussion before, and I still don't get it. :laugh:
I know our seasons come about because of the tilt of the earth's axis roughly 25.5 degrees, and I know "the sun doesn't set above the Artic Circle" in high summer. Yet as I visualize the sun "moving south" from the summer solstice to the autumn equinox, I still don't get why it doesn't get dark earlier "up north." It still seems counterfactual to me, even though I observed the phenomenon first had when I made my big cross-country train trip. It was later in the summer, and when the train stopped in northern Montana, it was light later in the evening than it would be back home. :laugh:
Maybe what I should do is the old science class trick of sticking a pencil through a styrofoam ball and moving it around a light bulb. ;D Then I have to make sure I have the pencil tilted enough and in the right direction. :laugh:
--- End quote ---
I think at least part of the explanation is that at the solstice, the days are longer farther north. So on June 21, the sun sets at 8:33 in Philadelphia, 9:03 in Minneapolis and 11:43 in in Anchorage. Daylight in northern cities must shrink more quickly after June 21, though. By Sept. 22 everybody's got 12 hours. Then northern daylight keeps shrinking faster until Dec. 21 -- although, weirdly, at that point sunsets in Philadelphia are only 5 minutes later than Minneapolis (3:34 and 4:39 respectively, but sunRISES are earlier in Philadelphia. Anchorage sunset on Dec. 21 is 3:41 p.m.
These times are affected not just by longitude but also by latitude -- that is, where the city is located within the time zone.
Jeff Wrangler:
--- Quote from: serious crayons on August 13, 2022, 10:32:19 am ---These times are affected not just by longitude but also by latitude -- that is, where the city is located within the time zone.
--- End quote ---
I'm afraid you have that backward. Latitude is how far north (or south) of the Equator you are. Longitude is how far you are located west (or east) of the Prime Meridien (which runs through Greenwich, England).
I don't know how they do it now, but conventionally latitude and longitude were both expressed in degrees, minutes, and seconds. Thus the latitude of Philadelphia is 39 degrees, 57 minutes, 9 seconds North. The longitude is 75 degrees, 9 minutes, 55 seconds West. (I spelled everything out because I don't know how to get the degree symbol.)
You can see this in action in Close Encounters, where the UFO guys are getting this stream of numbers, and somebody recognizes them as latitude and longitude coordinates (which turn out to be for Devil's Tower).
serious crayons:
--- Quote from: Jeff Wrangler on August 13, 2022, 02:29:28 pm ---I'm afraid you have that backward. Latitude is how far north (or south) of the Equator you are. Longitude is how far you are located west (or east) of the Prime Meridien (which runs through Greenwich, England).
--- End quote ---
Oops, yeah. I keep thinking the rule is that "longitude" is the longer one and therefore runs is north-south. Whereas the mnemonic I should be using is Jimmy Buffett!
CellarDweller:
--- Quote from: Jeff Wrangler on August 13, 2022, 02:29:28 pm ---You can see this in action in Close Encounters, where the UFO guys are getting this stream of numbers, and somebody recognizes them as latitude and longitude coordinates (which turn out to be for Devil's Tower).
--- End quote ---
and with this post, you made me want to find the scene from the movie where tones are being used for communication. Found it on YouTube.
Front-Ranger:
I was letting the cat out and I noticed a certain duskiness in the garden today. I went out and looked up at the sky. It was a boneless blue--no clouds. But the sun wasn't yet in the sky at 7 am. :-\
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version