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Star brightness versus star luminosity
Some extremely large and hot stars blaze away with the luminosity of a million suns! But other stars look bright only because they're near Earth.
February 18, 2017
Green Comet 45P: Photos and video
Green Comet 45P has been in our sky for months and passed closest on February 11, 2017. It's a faint one, but intrepid astronomers have captured some wonderful images!
February 12, 2017
See it! February 10-11 lunar eclipse
A penumbral eclipse is subtle, but has a quiet beauty all its own. Thank you to all who submitted photos of the February 10-11, 2017 eclipse!
February 11, 2017
How many eclipses in 1 calendar year?
Every calendar year has at least 4, but 5, 6 or even 7 eclipses are also possible. Why don't we see them all?
February 10, 2017
The ecliptic is the path of the sun
The ecliptic is an imaginary line that marks the path of the sun. You can also find the planets and moon near this line, tracing the plane of our solar system.
January 27, 2017
Favorite photos from this weekend
The EarthSky community on Facebook outdid itself posting photos over the weekend of January 20-22, 2017. Thanks, everybody! Editors' picks here.
January 22, 2017
Vesta, brightest asteroid, brightest for 2017
If you've never spotted an asteroid, now would be a good time to try. Vesta's 2017 opposition is around now. Guy Ottewell provides charts and explains more.
January 16, 2017
See it! First full moon of 2017
In the Northern Hemisphere, the January full moon is sometimes known as the Wolf Moon. Howl at these awesome photos of the January's full moon from EarthSky friends around the world.
January 13, 2017
Moon in 2017
Everything you want to know about the moon in 2017 - including phases, cycles, eclipses and supermoons - from world-renowned astronomer Fred Espenak.
January 10, 2017
