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Posts by
Larry Sessions
No leap second for December 31, 2021
World timekeepers have decreed there will be no leap second on December 31, 2021. Overall the spin of Earth is slowing down, but in 2020 it sped up.
December 31, 2021
The enduring mystique of Barnard’s Star
Sometimes called Barnard's Runaway Star, it's one of the best known stars in the history of astronomy and in popular culture.
November 14, 2021
Leo loses his tail. We gain a constellation
The constellation Leo once had a tail, a clump of faint stars. Now these same stars are known as Coma Berenices, the hair of a queen.
April 9, 2021
The Large Magellanic Cloud, a galactic neighbor
The Large Magellanic Cloud dwarf galaxy, visible all year round in the Southern Hemisphere, is somewhere between spiral and irregular in shape.
December 17, 2020
Find the Geminids’ radiant point
Why is the Geminid meteor shower best around 2 a.m.? It's because that's when the shower's radiant point - near the bright star Castor in the constellation Gemini - is highest in the sky.
December 11, 2020
Quarter moon or a half moon?
Half the moon always faces us. And half the moon is always lit by the sun. But, in the language of astronomers, there are no 'half moons.'
August 25, 2020
Moon phase a clue to the sun’s position
If you look in a clear western sky at dusk and early evening, you should spot the waxing crescent moon. Notice that its lighted crescent points toward the sunset.
December 31, 2019
First quarter moon on February 12
The side of the moon we see from Earth appears 50% illuminated tonight. For all of Earth, the moon rises around midday and sets around midnight. Plus the moon's lighted side points right at Mars tonight!
February 12, 2019
Moon, Pleiades, Aldebaran before dawn
A beautiful view of the waning crescent moon, Pleiades star cluster and bright star Aldebaran in the dark eastern skies before dawn on July 9 and 10.
July 8, 2018
10 surprises about our solar system
Here are 10 unexpected and intriguing facts about our solar system - our sun and its family of planets - you probably did not know!
March 26, 2018
