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 Kate’s
clams and we made some plans for the best use of our time.
Stumped on yesterday’s questions?
1.) How much less sun do we
get in Illinois every day from summer solstice (the longest day) to
As compared to:
2.) How much less sun Kotzebue
gets per day, until winter solstice?
And if I know that…I will be
able to determine…
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, I’m not
going to do it for you!
OK, let’s start with Illinois. We are
talking about ˝ 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 isn’t more than 1 hour’s difference in the
sunset time every day). So why not convert it to minutes first?
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?
Divide the number of minutes difference by the number of days.
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 doesn’t set all 365 days per year. There is
about 20 days of all light and 20 days of all day.
Take 365 – 40
(the number of days we aren’t counting) = __325___. Got it?
NOW take 325 / 2 = ________. This is the number of days.
long between sunsets? On the first day it’s 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,
don’t 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.
more about our project here
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