radiation
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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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Stars and Radiation
Stars are hot. Really hot. Hot enough to have energy to spare for their planets. If our star wasn’t hot, we couldn’t live on Earth. And our star isn’t even particularly hot for a star. It’s a middle-aged star of…
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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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Radio Astronomy: Advantages
Whoa…what’s this thing? It’s a radio telescope, the largest in the world. It’s so huge that a normal support system can’t support its weight. So it’s basically suspended between three mountaintops. It’s 300 m across, which is 1000 feet. It’s…
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Radio Astronomy: Limitations
Astronomy is a labor of love, and radio astronomy is no different. As I covered in my last post, radio astronomy deals with the longest wavelengths of the electromagnetic spectrum (a spectrum that includes visible light). Radio waves are not sound…
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Radio Astronomy
Ever seen one of these before? Yeah, it’s a bit bigger than your average radio antenna. That’s because its job isn’t to direct radio signals to your house. It’s a radio telescope, and its job is to collect as many radio…
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Interferometry
Imagine you have an image like one of these. This object is faint and faraway, so you can’t make out much more detail. You know that other stars like it — closer, brighter stars — have looked like this and…
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The Spectrum of Light
Does this look familiar? People think of rainbows as a symbol of happiness and fortune. There are even myths that leprechauns hide gold at the end of a rainbow. That’s more of a tease than good fortune, if you ask…
