Here's why February's full moon over southern Ontario might appear ...

If February’s full moon, also known as the snow moon, seems a tad smaller when it appears over southern Ontario officially on Saturday (Feb. 24) at 7:30 a.m. that’s because it is. It’s a micro moon.

The moon doesn’t change size, of course, but as Elaina Hyde, assistant professor in York University’s department of physics and astronomy and the director of its Allan I. Carswell Observatory, explained, it is farther away from Earth — so it seems smaller from our perspective.

“What happens, if you can imagine the moon is going around the Earth in a little bit of an eclipse, so sort of like an elongated squished circle. Not quite a football but just a little bit squished. So sometimes it’s a little bit closer and sometimes it’s a little bit farther away (from the earth),” she explained.

The average distance, she said, is about 382,000 kilometres.

It’s furthest point, she said, which gives us the micro moon, and is known as its apogee, is about 405,000 km.

The closest point, she said, which gives us a super moon, and is known as the perigee, is about 360,000 km.

She notes that because the moon is so far away to begin with, the size of the moon only changes a bit from our perspective on Earth.

“So from the biggest big moon to the smallest small moon it’s only about a 13 per cent size difference.”

Now if you’re wondering whether the distance of the moon plays a role in the timing of lunar missions the answer according to the Canadian Space Agency is ‘negligible’.

And they should know as they are part of the first crewed mission to the moon in half a century with astronaut Jeremy Hansen slated to join NASA’s Artemis II mission and become the first Canadian to fly around the moon as early as September 2025 (although this mission won’t land on the moon).

Now this writer assumed that the distance of the moon – whether near or far – would not be a factor in a lunar launch, and when asked to confirm that hunch, spokesperson Alyssa Roussy forwarded this explanation which, she said, is from the experts at the Canadian Space Agency.

“You are correct in that assumption that the actual distance from the Earth to the moon is a negligible factor in the determination of the launch time,” according to the statement from the Canadian Space Agency.

"The first burn to leave the Earth orbit and head toward the moon will take place on the side of the Earth opposite of the moon.”

And it’s that burn that “will send the spacecraft toward the moon where it will be attracted by its gravitational field. While the longer distance may mean the trajectory may take a bit more time, this does not translate into a significant amount of extra fuel, as the fuel is only used for manoeuvres, not for cruising.

“That being said, without being the main influencing factor, the moon distance is taken in consideration for Trajectory Design and Optimization, but the other factors, such as the moon phase, which drive the lighting conditions for the landing and the surface temperature during the mission, are more important in the determination of the launch window.”

For Hyde, of course, there’s always something of interest in the nighttime skies, and this time of year is no different.

“You have Jupiter, the planet Uranus, the Plaedeis (star cluster) and the moon all in a lovely line across your evening sky so that would be, I would say, a great reason to go out and, as they say, look up.”

As well, she said “the constellation of Orion is a wonderful winter constellation, it’s really spectacular right now because it’s high in the sky.”

It’s a “wonderful stargazing target”, she said, because it contains the red giant Betelgeuse, the blue super giant Rigel and the Orion Nebula.

“So even if you just have binoculars you can usually see a little bit of a difference between the red Betelgeuse and the blue Rigel, for example.”

York U’s observatory has “twice-a-week, every-week public outreach,” she advised.

“We have open tours every Wednesday and we also have an online public viewing where we show the telescope images on our YouTube channel every Monday.”

Both are free, but people are asked to register for free tickets to Wednesday’s public viewing. More information is available here.