Image from WikiCommons
My son, Spencer, lives in Boston and I live in Germany. We were talking on Skype and he sent me a picture he took last night. The picture was of the moon. He asked me if I’d seen the moon tonight? I had with my youngest son. We noticed the moon looked bigger than normal. Spencer said that tonight was a “super moon.”
What is a super moon?
The moon’s orbit around the Earth is an ellipse with one end closer to the Earth than the other. The closest point is called perigee and the farthest point away is called apogee. The difference in distance between the two is about 50,000 miles. There are two things that come together for a super moon.
A super moon occurs when the lunar phase and orbit of the moon are just perfect
The lunar phase is just under 30 days and is the full cycle of full moon to dark moon and back to full moon. The lunar phase is all about illumination. It’s the amount of sunlight we see on the Earth reflected back to us. This happens at every point in the moon’s orbit around us. We see a full moon just under every 30 days.
The orbit of the moon is just over 27 days. This is how long it takes the moon to travel one once around the Earth. The moon is at perigee once in those 27 days and at apogee just under two weeks later. When you look at the moon at the closest point and compare it to what you see at the farthest point, it appears to be 14% larger at perigee.
When would the moon look the most dramatic?
When the moon is closest to the Earth (at perigee) and during a full moon. These events cycle with slightly different lengths of time and align themselves about every 18 years. March 19th, tonight, is one of those days. The last one was in 1983.
Spencer asked me if I could see the moon? I could. We decided to take pictures of the moon at the same time. This is the picture I took:
Spencer said it looked like I had rotated the moon slightly to the right. He was in Boston, which is a few thousand miles to the East of me. We were fortunate to both have clear skies. After we compared notes, I wondered what happens to the Earth when the moon is at perigee.
The moon’s affect on the Earth at perigee is minor
The moon increased tides about an inch. In some geographic formations, the tides can rise up to seven inches. It certainly is nothing to worry about. It happens every month. Why are people interested in a super moon then?
The super moon is the biggest and brightest moon
The moon tonight was really beautiful. When my youngest son and I saw it earlier in the evening, it was lower in the sky and it looked gigantic. They say the best optical illusion is when the moon is on the horizon. We missed it on the horizon. I saw it later when it was higher in the night sky. The moon did look bigger to me when it was closer to the horizon.
I did have one problem with the super moon
I wanted to take a photograph of the super moon. I have a really nice still camera with a professional lens. Unfortunately, I am not a professional photographer. My first few attempts at taking a picture were horrible. I almost gave up.
I persevered and searched online for how to photograph the moon at night
Taking a picture of a full moon is like taking a picture of a light bulb in a dark room. I had my camera setup incorrectly. I ended up using 1/400th of a second shutter speed, with a 650 ISO and f/10 aperture. The higher I dialed up the ISO, the better the image became. That’s another thing I’ll work on later. Getting better at photography. Suffice it to say, that even with a hand held photograph, I was pleased I could see the craters on the moon!
The Super Moon doesn’t cause natural disasters. It’s a wonderfully beautiful moon to see. It seems like you can reach out and grab it. The light is very bright and it lights up the night sky. If you have a chance to see the next Super Moon, I highly suggest you do it. The next Super Moon will happen on Nov 14, 2016 so we don’t have too long to wait. Maybe I’ll have my camera figured out by then…
PS: You might enjoy this funny song about the moon