If you were to ask a child to draw a picture of the Sun, you would probably get something that looked like an orange – round and yellow. I’m not sure that most adults would do much different. That’s likely why Jack Sorensen had a second look when he spotted a flattened sun in the sky over Tryon, P.E.I.:
“I happened to look out the window this evening and thought this unusual, but I don’t know what it’s called.”
Scientists who have conducted precise measurements of its dimensions believe that the Sun is the most perfectly round natural object known in the universe. As a spinning ball of gas, astronomers expect our nearest star to bulge slightly at its equator, making it slightly flying-saucer-shaped.
So, what flattened the Sun over Tryon, P.E.I.? - the air.
When the Sun is low on the horizon, its rays travel through many layers of air. That is the case at sunrise and sunset. Refraction of light by these layers can make the sun appear flattened or distorted. The density and refractive index of the atmosphere decreases with altitude. The rays from the top and bottom portion of the Sun on the horizon are refracted by different degrees; this causes the apparent flattening of the Sun. That's why the Sun can appear oval at sunrise and sunset.
At noon, the Sun is overhead. The rays of light from the Sun enter the Earth's atmosphere normally, therefore, there is very little refraction or bending of light passing through the Earth's atmosphere. That’s why the Sun appears round at noon.
If you are curious about something in the sky, I’d love to help. Send a photo, if possible, and your questions to [email protected]
A few fun Sun facts:
- The temperature of the surface of the Sun is 5,500 degrees Celsius
- The temperature inside the Sun can reach 15 million degrees Celsius.
- One million Earths could fit inside the Sun.
- Light from the Sun takes eight minutes to reach the Earth.
- Want more weather information? Visit your weather page.
- Have a weather question, photo or drawing to share with Cindy Day? Email [email protected]
Cindy Day is the chief meteorologist for SaltWire Network
