The upcoming supermoon is going to be even more super than usual.
Astronomers say the supermoon due to grace the sky on Nov. 14 will be the largest apparent moon since 1948. amNewYork spoke with Emily Rice, a research associate at the American Museum of Natural History and assistant professor at CUNY College of Staten Island, to find out what exactly a supermoon is and how it’s different from other types of moons.
Here’s what we found out.
What is a supermoon?
A supermoon is when a full moon coincides with the moon’s closest approach to Earth on its elliptical orbit (which is known as perigee), Rice said, making the moon appear larger than usual.
Where did the term supermoon come from?
According to Rice, a supermoon isn’t even an astronomy term, it’s an astrology term – and yes, there’s a difference.
While astronomy studies the science of the universe, including stars, planets and galaxies, astrology is the study of how the movement of celestial bodies supposedly affects humans and nature on Earth.
But back to the supermoon: An astrologer in the late 1970s coined the term supermoon to describe when the full moon happens closest to perigee. The closest astronomy term for the supermoon would be syzygy, Rice said, which is when the Earth, moon and sun all line up. However, Rice also cautioned that the supermoon is just one type of syzygy, so the term can’t exclusively be said by this particular celestial event.
How many supermoons are there per year?
A supermoon happens only about once every 14 months, “so there won’t be any in 2017 at all,” Rice said.
This is the largest supermoon since 1948.
While it may seem that the supermoon happens all night, Rice said the peak closeness of the full moon to perigee occurs only for an instant, and that the exact timing can be calculated. Those figures show that this particular supermoon is the closest the full moon and perigee will happen in relation to each other since 1948. Rice said this supermoon is only “a few percent closer” than previous times, and some astronomers feel it’s being slightly hyperbolized. “I’m in favor of anything that gets people excited about looking up at the sky,” Rice added.
Date and time of the supermoon
Technically, the supermoon will occur on Monday, Nov. 14. In New York, the moon will rise at 5:13 p.m. and set on Nov. 15 at 6:26 a.m., according to the United States Naval Observatory.
But there’s a catch.
According to the USNO, the moon will hit its peak fullness at 8:52 a.m. EST (1:52 p.m. UST) on Nov. 14, which is daytime for New Yorkers.
Rice said perigee occurs at 6:24 a.m. EST on Nov. 14, and since the moon sets at 6:26 a.m. that day, early risers on Monday will have the best supermoon viewing.
“Either get up early in the morning on the 14th or stay up later on the 13th,” she added.
Will New Yorkers be able to see the supermoon?
This depends largely on the forecast. Sunday night is expected to be clear with a low of 41 near Central Park, according to the National Weather Service. On Monday night, it will be mostly cloudy with a 30 percent chance of rain after midnight — not the most ideal conditions for viewing the moon.