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11 July, 2003

A New Member on the Team

Today in Kotzebue
Today is lovely, sunny, warm (high of 54, but with the sunshine that is quite nice) and basically a great day to have off.

What Science Is Happening?
Honestly, not a lot. This is a prepare day. The boat is being prepared to hold the divers that arrived by plane today, Dr. Stephen Jewett and assistant Max. We just sorted out getting the diving equipment delivered. Kate and Lisa went out to take readings on Kateís clams and we made some plans for the best use of our time.

Classroom Connections:
Stumped on yesterdayís questions?
1.) How much less sun do we get in Illinois every day from summer solstice (the longest day) to winter solstice?
As compared to:
2.) How much less sun Kotzebue gets per day, until winter solstice?
And if I know thatÖI will be able to determineÖ
3.) What time will the sun set in Illinois and Kotzebue on July 30, September 30, and October 30th?

Let me help you a bit with the math. Get some scratch paper, Iím not going to do it for you!
OK, letís start with Illinois. We are talking about Ĺ of a year, right? How many days is that? 365 / 2 = _________.
Now the difference between sunset in the summer and sunset in the winter is 4 hours. I COULD divide by hours, but then my answer would be a decimal point and I have to convert it to minutes anyway right? (because there isnít more than 1 hourís difference in the sunset time every day). So why not convert it to minutes first?
How do you convert hours to minutes? You take 4 hours multiplied by what? Come on, you know!
Now you have 2 things, the number of days and the number of minutes difference in the sunsets. What should you do to find out how many minutes difference for ONE day?
Right! Divide. Divide the number of minutes difference by the number of days.
That gives you the difference per day.
Ok, now Kotzebue has the same math, but the numbers are different.
Number of days is NOT half of 365. Why? Because the sun doesnít set all 365 days per year. There is about 20 days of all light and 20 days of all day.
Take 365 Ė 40 (the number of days we arenít counting) = __325___. Got it?
NOW take 325 / 2 = ________. This is the number of days.
How long between sunsets? On the first day itís light all day and on the last day it is dark all day. The difference? 24 hours.
I need to change hours to minutes. 24 x ___???__ = _______
Now I have number of days and minutes per day. I need to????
Divide the number of minutes by the number of days.
Which sunset changes more everyday, Illinois or Kotzebue?
Now take your starting point. For Illinois it is 9:30. Why? Because that is sunset on June 21st. For every day you go subtract your number of minutes per day. For July 30th you have 39 days difference from June 21st. Multiply your number of minutes per day for Illinois by 39. (If the number is more than 60, donít forget to convert back to hours)
Same thing for Kotzebue. The first day with a sunset is July 10th. The difference between July 10th and 30th is 20 days. Multiply your minutes per day by 20 at 2:00a.m.
Now figure out the rest of the days.
I have confidence in you. Email me with you answers.


Learn more about our project here
View curriculum for this project, ďAsk a ScientistĒ and learn about other Arctic Real Time research at Arctic Alive
City of Kotzebue Webpage
Listen to the local radio station KOTZ live

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