What is orbital resonance? A dance between heavenly bodies

What is orbital resonance? It's a precise dance between heavenly bodies when their orbits line up, causing them to have specific synchronicities.

Groundhog Day is February 2. Phil says early spring!

It was a chilly 39 degrees F (3.8 C) this morning in Punxsutawney, PA, when Phil predicted an early spring. Happy Groundhog Day!

Here’s what ‘habitable’ means to astronomers

When astronomers say a distant world is 'habitable,' what do they mean? Do they mean humans could live there? Do they mean we've discovered alien life?

What makes the Harvest Moon special?

The Northern Hemisphere's Harvest Moon falls overnight September 17-18, 2024, or almost 5 days before the September equinox. It's also a supermoon!

1st of 5 new supermoons in a row starting today

We will have 5 new supermoons in a row, starting on January 11, 2024. The April 8, 2924, new supermoon will result in the April 8, 2024, total solar eclipse!

Which spiral arm of the Milky Way is ours?

Where do we live in the Milky Way galaxy? We lie between the major arms in a smaller spiral arm known as the Orion Arm. See diagrams here.

Are the December solstice and January perihelion related?

December solstice 2023 comes on December 21-22. Earth will be closest to the sun just 2 weeks later, on January 2-3. Coincidence?

What is a penumbral eclipse of the moon?

There are 3 kinds of lunar eclipses: total, partial and penumbral. A penumbral eclipse is very subtle. You can notice a shading on the moon's face.

What is the Milky Way? It’s our home galaxy

When someone says "Milky Way," do you think of the starry pathway across our sky, or of the great pinwheel-shaped galaxy in space? Both are correct!

Year’s earliest solar noon on November 3

November 3 brings the year's earliest solar noon - that is, earliest midday - by nature's clock. It's a harbinger of the Northern Hemisphere's earliest sunset.

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