Posts by 

Bruce McClure

Elnath is a bright star close to the galactic anticenter

The galactic anticenter is opposite the Milky Way's center from our viewpoint on Earth. The closest bright star to the anticenter is Taurus the Bull's Elnath.

Meet the Winter Circle, aka the Winter Hexagon

The brightest stars in the Northern Hemisphere's winter sky form the shape of the Winter Circle, or Hexagon, that will help you locate 6 constellations.

The Hyades star cluster: The Face of Taurus the Bull

Look for the V-shape Hyades star cluster in Taurus the Bull in the evening sky. It represents the Face of the Bull and it's beautiful in binoculars.

How far is a light-year? Plus, distances in space

How can we comprehend the distances to the stars and other galaxies? Here's a way to understand a light-year in terms miles and kilometers.

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 an astronomical unit?

An astronomical unit - or AU - is a measurement that astronomers use to describe distances in the solar system. Find out how long an AU is here.

What is stellar magnitude?

The brightest stars to the eye are 1st magnitude, and dimmest stars to the eye are 6th magnitude. How does stellar magnitude work in astronomy?

Planisphere: Your friend to find stars and constellations

A planisphere is an easy-to-use tool that can help you learn the night sky. Align the date and time to see what constellations and stars are overhead.

How often do 7 eclipses occur in 365 days?

It's rare to have 7 eclipses in a calendar year. It's less rare to have 7 eclipses in 365 days. There are 7 eclipses in 365 days 29 times in the 21st century!

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?

2026 Donation Campaign

If EarthSky has ever helped you discover something new, prepare for an eclipse, spot a planet, or simply inspired a moment of wonder, today is the perfect day to give back. Your donation helps keep trusted science news, expert night sky guides, and independent science journalism free for everyone.

Please help keep EarthSky going by donating today!

Please help keep

EarthSky going!

If you've already donated, we apologize for the popup and greatly appreciate your support.