Posts by 

Deborah Byrd

Are the December solstice and January perihelion related?

December solstice 2025 occurred on December 21. Earth will be closest to the sun about 2 weeks later, on January 3. Coincidence?

What is a full moon? All you need to know

The full moon, opposite the sun in its orbit, shows us its sunlit side. The moon appears full a couple of days before and after the exact moment of full moon.

Full Blue Moon on May 30-31, 2026: What’s a Blue Moon?

There's a full Blue Moon overnight on May 30-31, 2026. A Blue Moon is the 2nd of 2 full moons in a calendar month or the 3rd of 4 full moons in a single season.

Why is Venus so bright in our Earth’s sky?

You can't miss dazzling Venus in the east before dawn. It's the 3rd brightest object in the sky, after the sun and moon. But why is Venus so bright?

What’s a Blood Moon? All you need to know

By this definition, Blood Moon is a member of a special kind of lunar tetrad : four total lunar eclipses in a row. Now it's used for any total lunar eclipse.

What is a waning crescent moon?

A waning crescent moon can be found in the east before sunrise. It's waning toward new moon, that's when the moon will be between the Earth and the sun.

The moon illusion makes the moon look huge!

When you see a large-looking moon low in the sky, does the moon look bigger to you? That's the moon illusion that makes the moon look so big.

What is a last quarter moon?

The last quarter moon appears a week after full moon and a week before new moon. The moon appears half-lit, like half a pie.

The Big Dipper, the Pointers and Polaris

Want to find Polaris, the North Star? The entire northern sky turns around it. If you can find the Big Dipper, you can always find Polaris.

First quarter moon appears half-illuminated

The first quarter moon is halfway between new and full moon. Half of the moon is illuminated and it's a quarter of the way through it's orbit around the Earth.

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