1 February, 1998

Hello Again!

Our present position:
73 degrees 46 minutes south latitude
175 degrees 55 minutes east longitude

We had another fire drill today aboard the Research Vessel Ice Breaker 
Nathaniel B. Palmer.  It happened just as I was finishing lunch.  I 
dashed up to my room and gathered up my ECW gear (Extreme Cold Weather) 
and my life vest and my floatation suit. I went to the muster station 
just as my name was called off the list of passengers.  We were all 
present - even the people who were asleep.  

On this ship, we work around the clock - so there is always SOMEONE 
asleep. Our research team works in two shifts so that we are collecting 
and recording data around the clock. The Antarctic Support Associates 
make sure someone is available at all times for collecting the data in 
the computer and for working with the equipment that we are using to 
collect cores and sea floor images, and for working with all the 
electrical components. The ship does not run by itself, either!  It needs 
someone to steer it and someone to make sure the engines are working 
well.  And what about my favorite time of the day - meals?!  There are 
four meals a day aboard the ship.  There is breakfast from 7:30 to 8:30 
am, lunch from 11:30 am to 12:30 pm, dinner from 5:30-6:30 pm and 
"midrats" or midnight rations from 11:30 pm until 12:30 am!  Plus, there 
are always wonderful snacks - today there was chocolate cake and pie, and 
peanut butter Rice Krispie cookies (I ate five of these).  There is at 
least one chef working all the time.  It is amazing how may different 
types of jobs people do on the boat - everyone is needed.  Having so many 
helpful and skilled people makes our job of collecting scientific 
information so much easier and more pleasant!

The sun is starting to get lower in the sky at night.  It is still light 
out all day - but we have about three hours or so of  "night."  It 
actually is more like twilight.  Why is it light most of the time right 
now in Antarctica?  Is it ever dark all the time?  When?

Antarctica is at the South Pole.  The Earth's axis runs through the North 
Pole and the South Pole.  Our Earth turns on this axis once a day and our 
Earth circles the sun once each year.  Because our Earth's axis is 
tilted, the South Pole sometimes is tilted toward the sun as our Earth 
circles the sun. This means it is daylight at the South Pole during this 
time.  At the same time the North Pole is tilted away from the sun, so it 
is dark at the North Pole.   Sometimes the South Pole is tilted away from 
the sun and this means it is dark at the South Pole during this time.  At 
this time the North Pole is tilted toward the sun, so it is daylight.  

How long is it light in Antarctica? Our Earth circles the sun once a 
year, so the light pattern at the poles follows the seasons.  There are 
few days at the poles that have a dark night and a light day.  There is 
one long night and one long day!  The South Pole is tilted toward the sun 
during the southern summer (Austral Summer).  At this time, the North 
Pole is tilted away from the sun and it is the North Pole winter.  If you 
live in the Northern Hemisphere (top half of the globe) your winter days 
are probably shorter than your summer days because of this tilt.  During 
the Austral winter, the South Pole is tilted away from the sun and it is 
dark all the time.  The North Pole is tilted toward the sun at this time, 
so this is the North Pole summer.  Are your summer days longer?  Did you 
know that the seasons were opposite in the Northern Hemisphere and the 
Southern Hemisphere (bottom half of the globe)?  

You can see how the seasons work and why the poles experience a long 
winter night and a long summer day.  You will need a Styrofoam ball, a 
lamp, some markers, and two tooth picks.  

On your Styrofoam ball make an outline of Antarctica and of the Arctic 
Ocean.  Be sure to put them "in the right place!"  Now poke a toothpick 
into the South Pole and one into the North Pole so that an inch still 
sticks out from each.  Can you make your "Earth" spin on its toothpick 
axis?  Our Earth spins once a day on its axis.  The lamp will be the 
"sun."  Think of the face of a clock.  Tilt the toothpick axis of your 
Earth so that the South Pole would be about 7:00 and the North Pole would 
be at about 1:00.  Keep that tilt steady.  Hold your Earth by the North 
Pole and make it circle the sun.  Watch what happens to Antarctica.  Can 
you see it go from bright when it is facing the lamp to dark when it is 
facing away from the sun?  What happens in the Northern Hemisphere?  

The movement of your tilted Earth around the light bulb shows you why 
Antarctica is light for half the year (summer) and dark for the other 
half (winter). If you make your Earth spin on its toothpick axis while 
you move it around the sun (this will be a challenge!), you will see that 
Antarctica still gets light for half its yearly journey around the sun 
and it is dark for the other half!

More soon from the Palmer!

Yours Truly,

E. Shackleton Bear