A 24 Hour Sundial

..and tough questions from Mr. Dave!

Hello Everyone,

February 21 is the first sunset of the year in McMurdo, Antarctica. McMurdo can be found on some maps, but to help you it is located on Ross Island in the Ross Sea. If you can find New Zealand, go south about 2000 miles and you are here. I am here in McMurdo for the winter.

At this time of year, we have 24 hours of daylight, and in June the sun will never rise. The differences between what most people see in the year, and what I see here bring up some questions. Please feel free to answer the questions to the list-server. In a week or so, I will send my answers. I do not always have the answers, so let's work together.

As I write this, it is Tuesday February 20, but in the USA it is Monday February 19. This means if I email this today, you can read this letter before I write it. How can this be? If asked of most school students in the USA, where is the sun going to set, the answer would be in the west.

Where is the sun going to set here on February 21?

I am sure you all have seen a sundial. It is an old timepiece that uses a shadow to tell the time. It has a center upright piece to create the shadow, and numbers around the edge. Most sundials I have seen do not have enough numbers for the summer here when the sun is up 24 hours a day. Please help me by drawing a sundial so I would know how to make a 24 hour sundial to use here. (Possibly someone with a scanner can help by loading up some drawings) When installing a sundial in the USA, one could orient the sundial by using a compass to point the 12 marker to the north. If I had a compass here in McMurdo, how should I set up the sundial?

I have already told you that February 21 is the first sunset of the year. From that point, the hours of daylight will be less every day. Before winter (which is the time of summer in the USA), we will see the final sunset before a few months of no sunrises.

When will the final sunset happen before winter?

Once the sun is down, I will be able to see the moon. I have seen the moon a few times here, but not well because of the sunlight. When the moon can be clearly seen, will the man in the moon be upside down?

I have heard the stars are hard to see in the town of McMurdo because of all the light, but out of town the stars are very beautiful. I am not good at picking out constellations, but I can usually find The Big and Little Dipper and Orion.

Will I be able to see them from here? In the Arctic they have the northern lights. Will I see anything like that here in the Antarctic?

I am sure this will keep you thinking for a while. Please participate by sending in you answers to the listserv. Dave Hess

David Hess NK3T

Presently living in beautiful downtown McMurdo, Antarctica.

Patricia A. Weeg
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