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Index of Subjects ------=_Part_184878_17987841.1174522603719 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline The reason for this occurrence is that the Earth's axis of rotation (one rotation = one day) is 23 degrees or so different from the axis of revolution (one revolution = one year = one trip around the sun). If these axes were the same, there would be no changes in the length of a day, as well as no change in seasons. For different points on Earth, this would mean different things. At the equator, this would mean that the day and the night would each be exactly 12 hours long (half of one rotation). At the poles, this would mean the sun was always right on the horizon, half up, half set. However, since Earth's rotation axis is tilted relative to its revolution axis, the length of day varies. At the equator, this effect is the least noticeable, with day and night always being close to the same duration. At the extreme latitudes however, this means that in spring when the north pole "wobbles" toward the sun, the sun is visible nearly all "day" long, ie., for the entire duration of the rotational period. The inverse is true as fall turns to winter; when the north pole is tilted "away" from the sun, the sun is nearly always set, resulting in hardly any direct sunlight. I hope my attendance in Physics 271 has paid off. Bruce On 3/21/07, Andy Moir/Chris Callaghan <andyandchris@ns.sympatico.ca> wrote: > > This morning on CBC radio, they talked with a person who lives way up > north. (I didn't catch the location, but they said it was the most northerly > year-round settlement in Canada). The question they were asking was about > what Spring means to various parts of the country. One thing he said is > that as of April 1st, his community will have sunlight 24 hours a day. (I > think he said sunlight, because he talked about the sun going behind the > mountains, but suggested that if there were no mountains, he'd be able to > see the sun 24 hours a day). I tried, unsuccessfully, to find a webpage > that would explain to me why there would be 24 hours of light that far north > at this time of year, when we're in darkness by 8 pm. Can someone suggest a > webpage that has diagrams that would explain this to me...or perhaps someone > can offer an explanation. > Thanks, > Andy Moir > Freeport > ------=_Part_184878_17987841.1174522603719 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline The reason for this occurrence is that the Earth's axis of rotation (one rotation = one day) is 23 degrees or so different from the axis of revolution (one revolution = one year = one trip around the sun). If these axes were the same, there would be no changes in the length of a day, as well as no change in seasons. For different points on Earth, this would mean different things. At the equator, this would mean that the day and the night would each be exactly 12 hours long (half of one rotation). At the poles, this would mean the sun was always right on the horizon, half up, half set. However, since Earth's rotation axis is tilted relative to its revolution axis, the length of day varies. At the equator, this effect is the least noticeable, with day and night always being close to the same duration. At the extreme latitudes however, this means that in spring when the north pole "wobbles" toward the sun, the sun is visible nearly all "day" long, ie., for the entire duration of the rotational period. The inverse is true as fall turns to winter; when the north pole is tilted "away" from the sun, the sun is nearly always set, resulting in hardly any direct sunlight. <br><br>I hope my attendance in Physics 271 has paid off.<br><br>Bruce<br><br><div><span class="gmail_quote">On 3/21/07, <b class="gmail_sendername">Andy Moir/Chris Callaghan</b> <<a href="mailto:andyandchris@ns.sympatico.ca" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)"> andyandchris@ns.sympatico.ca</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> <div bgcolor="#ffffff"> <div><font face="Arial" size="2">This morning on CBC radio, they talked with a person who lives way up north. (I didn't catch the location, but they said it was the most northerly year-round settlement in Canada). The question they were asking was about what Spring means to various parts of the country. One thing he said is that as of April 1st, his community will have sunlight 24 hours a day. (I think he said sunlight, because he talked about the sun going behind the mountains, but suggested that if there were no mountains, he'd be able to see the sun 24 hours a day). I tried, unsuccessfully, to find a webpage that would explain to me why there would be 24 hours of light that far north at this time of year, when we're in darkness by 8 pm. Can someone suggest a webpage that has diagrams that would explain this to me...or perhaps someone can offer an explanation.</font></div> <div><font face="Arial" size="2">Thanks,</font></div> <div><font face="Arial" size="2">Andy Moir</font></div> <div><font face="Arial" size="2">Freeport</font></div></div> </blockquote></div><br> ------=_Part_184878_17987841.1174522603719--
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