space
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What is a Lunar Eclipse?
March 2024: This post has been updated and republished from Sept 2017. Show of hands — who’s heard about the lunar eclipse coming up on March 14? As I always do for eclipses, both solar and lunar, I’ve spruced up…
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What is Coronal Gas?
Stars are hot. Space is cold. We’re all familiar with that, right? Ok, good. Technically, it’s more complicated than that. Space isn’t completely frigid — absolute zero, the temperature at which there is no heat whatsoever, is purely theoretical and not…
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What Causes the Lunar Phases?
We see it almost every night of our lives. For thousands of years, the greatest philosophers and astronomers alike have watched its face change and wondered why. Step outside and observe the moon every day for a month and you…
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Distances Between Stars
When you look up into the sky on a clear night away from the glare of the city, you see trillions upon trillions of stars. Thousands of years ago, the classical astronomers saw the same thing you do today — except…
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Types of Stars
Meet the sun: a G2 class star towards the middle of its lifespan. Wait a second…G2? What does that even mean? It’s all part of a way astronomers break down the billions of stars in the sky and organize them…
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The Atomic Spectrum
Astronomers know that if white light passes through a prism and is bent, it’s separated out into its component colors — the colors of the rainbow. Astronomers also know that when light interacts with atoms, the building blocks of the…
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Atoms and Radiation
Everything we know about space comes from radiation. Now wait just a moment here. That statement explains how astronomy is such a successful field of science — it’s based entirely on the information we can glean from radiation, after all.…
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Cosmic Rays
Cosmic rays remain, for the most part, a cosmic mystery. But then, what about the universe doesn’t still remain partially shrouded in mystery? Cosmic rays are radiation, but they’re not electromagnetic. That is, they’re not on the electromagnetic spectrum. So,…
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Infrared & High-Energy Astronomy
You probably recognize this image. You see something like it whenever you look up at the sky. Some days are clearer than others — some, you might even see a completely blue sky — but regardless, you know that this…
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The Hubble Space Telescope
The Hubble Space Telescope is one of the most famous telescopes in the world. Oops, excuse me — one of the most famous telescopes built. Hubble, after all, is certainly not in this world. Unless you call the universe the “world,”…
