Posts by 

Deborah Byrd

What is a new moon? It rises and sets with the sun

The new moon generally can't be seen, except during a solar eclipse. The moon crosses the sky with the sun during the day, and its shadow side faces Earth.

What’s the youngest moon you can see with your eye alone?

It has long been a sport for skywatchers to spot the youngest moon after sunset, with the eye alone. What does it take to see a very young crescent moon?

What is a waxing crescent moon?

A waxing crescent moon shines in the west after sunset, first visible a day or two after new moon with earthshine. It sets after the sun after sunset.

Uranus at opposition on November 25, 2026

Don't miss Uranus at opposition on November 25, 2026. At this time, it's brightest for the year and visible to the eye under optimum observing conditions.

How to know your eclipse glasses are safe

Unscrupulous companies are printing ISO certification labels on fake eclipse glasses. Check here for reputable vendors from the American Astronomical Society.

Why are stars so bright on winter nights?

In December, January and February, we look away from the Milky Way's cloudy core toward the Orion spiral arm, with stars so bright they capture our attention.

Apollo 8 Earthrise photo Christmas Eve 1968

Astronaut William Anders took this iconic photo of Earthrise on the 4th orbit of the moon aboard Apollo 8 on December 24, 1968.

What was the Christmas star? Science and mystery

What was the Christmas star? Some scientific explanations attempt to explain the Star of Bethlehem, including a planetary conjunction, comet or supernova.

Astronomers create 1st map of the sun’s outer boundary

Astronomers have produced the 1st map of the sun's outer boundary, the point-of-no-return for material that escapes the sun's magnetic grasp.

Mysterious 3200 Phaethon is the Geminids’ parent object

3200 Phaethon is the weird comet-like asteroid that spawns the Geminid meteor shower. New research reveals more answers ... and questions.

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