Remember to do what you can to take measurements of the sun from your location on December 21st, 2014 (next Sunday). I know this will be most difficult for those of us in the northern hemisphere because we have been dealing with chronic overcast and we cannot measure the sun or shadows if we cannot see it. I’m especially interested in any measurements from the southern hemisphere. But we will also try the northern hemisphere as well.
However, if you can remember, next Sunday, Dec 21st, try to do the best you can to estimate and obtain the following measurements. (We will also do the same on June 21st, 2015).
You must use a flat horizon to do these measurements. Hills and mountains will obscure the results.
Using the points on a clock face, you will be standing at the center of the clock facing due south:
- Due south would be 12 on your clock face.
- Directly to your right is West and 3 on your clock face.
- Directly to your left is East and 9 on your clock face.
At sunrise, when the sun is in direct contact with the horizon, tell us where on your clock the sun is located on the horizon. It should be between 9 and 12 on your clock. Tell us your best guess.
At Noon standard time, using a pole as your measuring device, tell us the exact height of your pole above ground level and tell us the exact length of the shadow produced at exactly noon sharp. The ground around your pole should be flat and smooth. Your pole needs to be exactly vertical so use a bubble level on all 4 sides of your pole to ensure it is vertical and not leaning. The pole should be at least 4 ft tall. You can check the levels the day before the measurement. Don’t wait until noon of the 21st to do so, because we need your shadow measurements at NOON sharp.
At sunset, when the sun is in direct contact with the horizon, tell us on where on your clock the sun is located on your horizon. It should be between 12 and 3 on your clock. Tell us your best guess.
If you like, you can also try to measure the angle of the shadows produced by your pole at exactly sunrise and sunset and include those results but this is much more difficult to be accurate as to angle. Your visual estimate of the horizon location of the sun on the clock face as to where you see the sun rising and setting is more important.
We will also need to know your location. Do not give us your personal info or address. We only need to know the name of the local city, state and country where you are located. Latitude and longitude from Google earth or GPS is also ok… but I would prefer that it didn’t pinpoint your exact location since this is a public internet posting. The nearest large city to your location would be best. We are just trying to get a basic idea of the sun. Last year was the first significant increase since the major shift in Dec 2004.
Obtaining accurate measurements is very hard for those of us in the northern hemisphere to estimate in the winter time. Our best measurements will come from those who live in the southern hemisphere. But we will do our best to see what info we can get. The more, the better. Obviously, you cannot measure if the sky is obscured with overcast. So if you cannot get all three, we will be happy to receive even one measurement. We also realize that you may only have flat land on one side, so we will take any measurements you can do from your location. Obviously, our summer measurements will be much easier and efficient. But we will give this winter measurement a try.
If you are unable to obtain the measurements on Dec 21st due to overcast or other problems, we will take measurements up to 10 days after the 21st, but they will be less accurate. If this occurs, please tell us the exact date of your measurements as close to the 21st as possible.