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Posts by
Editors of EarthSky
Neptune at opposition on September 26, 2026
Neptune at opposition -- when it's opposite the sun on the sky's dome -- comes on September 26, 2026. You'll need optical aid to spot it.
September 25, 2026
Astronomy Essentials
Seeing Saturn’s rings: Top tips for beginners
If you want to see Saturn's rings, late September and early October 2026 is a great time to look. Grab a telescope and read the tips found here!
September 25, 2026
Full moon names by the month and by the season
Lists of common full moon names — both by month and by season — for North America. And a word about full moon names in the Southern Hemisphere.
September 24, 2026
Are day and night equal on the equinox? Not exactly
Are day and night equal at an equinox? No. There's slightly more day than night on the day of an equinox. Find out why here.
September 22, 2026
The equinox sun rises due east and sets due west
The 2026 September equinox occurs at 00:05 UTC on September 23, 2026. And the equinox sun rises and sets due east and due west.
September 20, 2026
Crepuscular rays are sunrays in twilight skies
Crepuscular rays form around twilight when particles in the atmosphere reflect the sun's light beams toward our eyes. See photos of the phenomenon here.
September 13, 2026
What is retrograde motion? And why is the moon moving backwards?
What is retrograde motion? See an image that appears to show the moon moving backwards! An explanation, and more bizarre examples, here.
September 11, 2026
How many stars can you see on a moonless night?
Have you ever wondered how many stars are visible on a given night? It depends on factors including how dark your sky is and what your age is.
September 9, 2026
Cassiopeia the Queen ascends in September and October
Cassiopeia the Queen is an easy-to-find constellation. It has the shape of a W or M. Look for it in the north-northeast sky on September and October evenings.
September 4, 2026
Roman space telescope has launched! You can adopt a pixel
The Nancy Grace Roman Space Telescope launched on August 30 from the Kennedy Space Center. Want to add your name to a pixel? Find out how here!
September 2, 2026
