spectral lines
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Star Luminosity Classes
What do you think it would mean for a star to be in a specific luminosity class? I mean…does that mean they go to school to learn how to be bright? (Ha, ha…yeah, I know, bad astronomy pun.) Well…not quite.…
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The H-R Diagram
There are 250 billion stars in our galaxy alone. Many are much like the sun, labeled with the Latin sol for “sun” in this diagram. But many more are not quite what we might expect stars to be like, after living…
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Stars and Proper Motion
Recognize this constellation? Well, at the time stamp of about 2000 AD (CE), I think you will. It’s one of the most famous constellations in the night sky. Well, technically, it’s not a constellation at all. It’s an asterism — a…
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Spots on the Sun
Have you ever looked at the sun, and seen something like this? Now, before you decide to look at it right now and see what you see, it’s my responsibility as an amateur astronomer to remind you of the safety…
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Our Sun: The Chromosphere
This diagram is a tiny bit misleading. Here, it looks like the chromosphere is the visible surface of the sun, with the photosphere just below. Really, we never see the chromosphere. If you ever look through a solar telescope at…
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The Doppler Effect
Have you ever heard the ice cream truck? When I was little, I remember hearing the ice cream truck all the time. Just the sound of the opening notes of “Pop Goes the Weasel” were enough to propel me to…
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Star Stuff & Cecilia Payne
If this quote really is from Cecilia Payne, then she had the right idea — at least for a female astronomer in the 1920s. Women in science back then faced an uphill battle to get recognized for any discoveries they…
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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 Balmer Thermometer
How hot would you say this star is? Take a wild guess. Well…sorry, but I’m going to stop you for a moment just to make sure we’re all using Kelvins. The Kelvin scale is like the Celsius scale, except water…
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The Building Blocks of the Universe
“The Building Blocks of the Universe.” When you put it that way, atoms sound less like a topic specifically for a chemistry class and more like something astronomers might discuss. They really are. I’ve got a fantastic reason to include…
