Last chance to see rare celestial event for decades
What do werewolves, insanity, falling in love, and bright full moons have in common? While these are recurrent motives in Stephen King novels, they are more commonly associated with lunar eclipses. This Sunday, Sept. 27, Sackville will be treated to the first supermoon lunar eclipse in over 30 years, during which a lunar eclipse will coincide with the moon’s closest passage to the Earth. This combination of celestial events is extremely rare, and is not set to occur again until 2033.
A lunar eclipse occurs when the Earth passes in between the sun and the moon, causing the moon to be covered by the Earth’s shadow from our perspective. From Sackville’s perspective, the moon will start to enter the penumbra, or the outer edge of the Earth’s shadow, at about 9 p.m. The moon will appear slightly darker than normal. At about 10 p.m. the moon will enter the umbra, or the darker part of the Earth’s shadow. This will look like a portion of the moon is starting to disappear.
This lunar eclipse will be a total eclipse, meaning that the moon will be completely covered by the Earth’s umbra. Most eclipses are partial eclipses, where the Earth’s umbra covers only a certain portion of the moon. The total eclipse will happen shortly after 11 p.m. here in Sackville.
“During totality, the moon often appears reddish in colour because of the way light gets bent as it passes through Earth’s atmosphere,” said Catherine Lovekin, an assistant professor in Mount Allison’s department of physics. “This is why you might see some news articles talking about the ‘blood moon.’”
The moon looks red during an eclipse for the same reason the sky can look red at sunset. The “blood moon” will last for about an hour, and then the moon will move back in the penumbra and eventually out of the Earth’s shadow altogether.
This eclipse should be over at about 1:30 a.m., “[At which point] the exciting parts are done, and everyone can go home and go to bed!” said Lovekin.
What makes this lunar eclipse an especially rare event is that it is going to occur during a so-called supermoon. Since the moon’s orbit around the Earth takes a more elliptical path than a circular one, there are periods when the moon and Earth are farther apart or closer together. The lunar eclipse this Sunday is going to take place when the sun and moon are at their closest point, called the perigee. As a result, the moon will look slightly larger in the sky than it would if the sun and the moon were farther apart.
Lovekin encourages people to take advantage of this opportunity by taking some time to view the eclipse.
“If the weather here cooperates, we should have a really good view,” said Lovekin.
The eclipse will be easily visible in the southeastern sky, moving to the southern sky at the completion of the event. Weather permitting, Mt. A’s Gemini Observatory will be opened for viewing through its telescope and binoculars. Both Lovekin and the astronomy technician Robert Sorba will be on site to answer questions.