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Posts by
Bruce McClure
How to find the Winter Hexagon or Winter Circle
The brightest stars in the Northern Hemisphere's winter sky form the shape of the Winter Hexagon or Circle, that will help you locate 6 constellations.
January 19, 2023
How do you measure the mass of a star?
Binary stars - a star system consisting of two stars - are extremely useful. They give all the information needed to measure mass of a star. Here is how.
January 15, 2023
Happy Friday the 13th
When a year with 365 days starts on a Sunday, like 2023, it's inevitable Friday the 13th will occur twice. They will occur in January and October in 2023.
January 13, 2023
Sirius is a future southern Pole Star
Wait, what? It's true. The sky's brightest star, Sirius aka the Dog Star, will come to within 1.6 degrees of the south celestial pole in the year 66270.
January 5, 2023
The star Sirius rings in the New Year
The Dog Star Sirius reaches its highest point in the sky around midnight every New Year's Eve. For this reason, it could also be called the New Year's star.
December 31, 2022
How to use EarthSky’s lunar calendar
Live by the moon! Here’s why you need an EarthSky lunar calendar, the top tips for using it, and where you can order one.
December 31, 2022
Meet Pisces the Fish, 1st constellation of the zodiac
Pisces the Fish is a zodiac constellation that is high in the sky on December evenings. Look for it and its asterism, the Circlet of Pisces.
December 18, 2022
Longest days accompany the December solstice
The longest days accompany the winter solstice. In December, a day - a whole cycle of day and night - is about half a minute longer than the average 24 hours.
December 18, 2022
The Orion Nebula is a starry nursery
You can see the Orion Nebula as a fuzzy spot in the sky using just your eyes. It's really a vast cloud in space where new stars are forming. Learn more.
December 16, 2022
Earliest sunset comes before winter solstice
Earliest sunset at mid-northern latitudes are happening now. What if you're in the Southern Hemisphere? Watch for your earliest sunrise.
December 3, 2022
