Hey, sky fans! Been a busy week down here at SkyWatch HQ. I hope you’ve had a great week.
October’s full Moon, in your skies this coming weekend is called the Hunter’s Moon. The Hunter’s Moon is actually the full Moon after the Harvest Moon, which is the name for the full Moon closest to the autumnal equinox, which was in September here in the northern hemisphere.
With leaves changing and the weather cooling, the Sun is setting earlier. This means the full Moon, which rises at about the same time the Sun sets, is rising earlier and is in the skies for a longer time than it was just a month or two ago. The bright moonlight gives hunters more time to hunt at night before the colder winter weather comes along and freezes the whole thing out. For most people, the Moon will look its fullest Saturday night, the 15th, but depending on your timing and where you are, it might look its fullest on the 16th, Sunday. For North America, have a look on Saturday.
Have you seen the Moonrises over the last few days? You might have noticed they’re earlier, true, but they’re also a bit bigger, and stand out more against the afternoons’ blue skies. Imagine something that’s already gorgeous, even more gorgeous. It’s been a terrific set of late afternoons with the early sunset glow in the west and the Moon etched into the skies not far away.
As you might remember, the Moon is closer to the Earth at certain points in its orbit than at other points, because the Moon’s orbit isn’t a perfect circle. We’ve talked about this before, with the Earth’s orbit around the Sun, too. The farthest point in the Moon’s orbit around the Earth is called its apogee, and is about 252,000 miles (406,000 km). The closest point is its perigee, and is about 226,000 miles (363,000 km). Together, we get an average distance of about 239,000 miles (385,000 km).
As it turns out, this month’s full Moon is happening around when the Moon at perigee, which is on Sunday. So, the Moon will appear a bit bigger and a bit brighter than it otherwise would. Apogees and perigees happen every lunar month, as do full Moons, but the two together don’t happen all the time. So, it’s always a little special. Some people like to call this a Supermoon.
No matter what you call the full Moon, it’s always a great show, bright and gorgeous. Though, if you have plans to look at stars, you might want to reschedule them. The Moon is so bright, the brightest thing in the entire sky other than the Sun, that it easily washes out stars clear across the dome. It’s great, though, and I always love seeing our closest neighbor, rising up from the hills near my house, especially when the nights get longer, and especially especially when it’s near perigee.
Look for the Moon low (of course it’s low; it’s rising) and big in the sky to the east just after Sunset. It’ll be rising from behind the horizon, cacti taxis, giraffes, and whatever else, and might look to be a bit orange. This isn’t because of an eclipse. It’s because of extra scattering of its light in the Earth’s atmosphere when its low in the sky. The light needs to travel through more of the atmosphere to get to you than it does when the Moon is high overhead.
I hope you can get out and see it this weekend.
Until next time, clear skies, everyone!