Understand how the tilted rotation of Earth's axis gives more prominent full moon in winter than in summer


Understand how the tilted rotation of Earth's axis gives more prominent full moon in winter than in summer
Understand how the tilted rotation of Earth's axis gives more prominent full moon in winter than in summer
Learn why a full moon is more prominent in winter than in summer.
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Transcript

Winter is unquestionably the best season for skiing and for full moons. We're lucky enough to have winters because the Earth's plane of rotation is tilted relative to its orbit. This means that when part of the Earth is tilted towards the sun, the sun stays in the sky for a longer amount of time each day, and it's warm out-- summer.

Of course, six months later when that part of the Earth is tilted away from the sun, the sun is lower in the sky and doesn't stay up as long. This might make winter darker, but you can think of it as bonus time pointing towards interstellar space. And as I said before, winter has the best full moons.

The moon is new when it's on the same side of the earth as the sun, and it doesn't reflect any light on us. This also means the new moon generally mirrors the sun on its journey across the sky. It more or less rises and sets at the same time as the sun and follows a similar path.

On the other hand, the moon is full when it's on the opposite side of the earth from the sun. Its whole face reflecting the sun's light back at us. Because of this opposite position, a full moon is only ever up at night, rising at sunset and setting at sunrise.

And it consequently also behaves the way the sun does in the opposite season. That's because when a part of the Earth is tilted towards the full moon, it's tilted away from the sun and vice versa. So a summer full moon is like a winter sun, only appearing for a few hours and staying close to the horizon.

But a winter full moon is like a summer sun. It's up for a long time and takes a high path through the sky. In the darkest months, the moon, at least when it's full, gives us long, beautifully lit nights. Combined with a quiet blanket of snow and the shimmering aurora, how can you not love winter?