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What is a Solar Eclipse?
March 2024: This post has been updated and republished from Sept 2017. A solar eclipse is the most amazing astronomical sight you’ll ever see. Not only is it the only time you’ll ever be able to clearly see the “new…
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How Big and Bright are Galaxies?
The brightest galaxy in our night sky is the Andromeda Galaxy, our nearest intergalactic neighbor. Hey…notice we’re talking about intergalactic neighbors now? 😀 In most of the posts on this blog, we’ve talked about interstellar neighbors, interstellar space, etc. But…
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How Far Away are Galaxies?
Well, I’ll give you a spoiler: they’re ridiculously far away. Let’s consider for a moment what a light-year actually means. It sounds like a unit of time, but it’s actually the distance that light travels in one Earth year. Think…
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How Big is the Milky Way?
How big is our galaxy, anyway? And more than that — how do we know? Consider that we can’t really take a photo like this of our galaxy. We’re inside it, and space travel has not advanced to the point…
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The Celestial Sphere
When you look up at the night sky on a clear, dark night, it seems as if the stars are glittering like bright thumbtacks on a great canvas above you. (You can get a similar effect — with less light…
