On the night of May 15, a Blood Moon will rise, and it’ll be the longest total lunar eclipse that Canadians have been able to see in 15 years.
A total lunar eclipse occurs when the sun, Earth and moon line up so that the Earth blocks the sun and its shadow falls directly on the face of the moon.
The moon’s nightly glow comes from reflected light from the sun. During a lunar eclipse, as the moon crosses into the Earth’s umbra — the fullest part of the Earth’s shadow — its usually bright white shine will rust into a darker, redder colour, giving it the unofficial moniker of a Blood Moon. A little more than a third of all lunar eclipses are total eclipses.
According to NASA, the moon will start crossing into the Earth’s shadow shortly after 10 p.m. (EDT) on May 15, but will be entering the umbra around 11 p.m., marking the start of the eclipse.
While the moon passes into the umbra during partial eclipse, it will appear to our naked eyes as if parts of the moon are simply being swallowed by darkness — but once the moon is fully eclipsed, that darkness will become visible as a reddish hue as our eyes adjust.
By around 11:30 p.m. (EDT), the moon will be fully copper-coloured.
The Blood Moon will be at its greatest eclipse at 12:11 a.m. (EDT) on May 16, and will be exiting the umbra around 1 a.m. By 1:30 a.m., it will be only halfway eclipsed, and by 2:00 a.m., it should have fully escaped Earth’s shadow.
This eclipse should be visible from coast to coast in Canada, though the exact rise and set of the eclipse is different depending on time zones.
An animated map made by NASA shows how the eclipse will progress as the Earth spins, showing which regions of the Earth will be able to see the eclipse at which stage.
Those in eastern and central Canada will have a slightly better view — the moon will have already risen in the night sky by the time it begins to eclipse, meaning eastern provinces will be able to watch the full eclipse progress depending on weather-related visibility that night.
But in the western provinces, the Moon will be rising while already starting to eclipse, making it more difficult to see while it is close to the horizon. Those in the northern regions of Northwest Territories and Yukon may only catch the tail end of the eclipse, or may be unable to see it if they are too far north.
The Moon will be fully eclipsed for around 85 minutes, or nearly an hour and a half. According to The Weather Network, this will be the longest total eclipse visible from Canada since 2007.
This eclipse also occurs when the moon is near perigee, NASA says, which means the moon appears seven per cent larger than average. Perigee is the point in the moon’s orbit when it swings the closest to our planet.
The next total lunar eclipse visible in Canada will be happening in November 2022, and will be visible across the entire country.