redshift
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Cosmological Redshift Demystified
If you’ve been following my recent posts, cosmological redshift will likely be a familiar idea. I introduced it in my post on the Hubble Law. We revisited it again in our discussion of the size and brightness of galaxies. When…
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The Cosmic Microwave Background Radiation
What if I told you that this was an actual image of the night sky? Well…alright, I admit it’s more like a map. Specifically, a map of the cosmic microwave background radiation, often known simply as the CMB. This is…
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What is Cosmology?
Cosmology is the study of the universe itself: how it came to be, how it has behaved since, and why the laws of physics operate the way they do. It’s one of the strangest branches of science — second only,…
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A Full Story of Galactic Evolution
Over the course of the last few posts, we’ve explored different types of active galactic nuclei: Seyfert galaxies, double-lobed radio sources, and quasars. At the heart of each of these galaxies lies a supermassive black hole, feeding off an energy…
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What the Heck is a Quasar?
I’ll give you a hint: this is not an image of a quasar. This image is from a first-season Star Trek: The Original Series episode, “The Galileo Seven” — the original footage, before it was remastered (and before astronomers had…
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Galaxies Demystified
From the smallest of irregular and dwarf galaxies, to the most spectacular of spirals, to the most massive of ellipticals, there’s no denying that galaxies are incredible objects. On this blog, we’ve covered a great deal of information about galaxies.…
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What is the Hubble Law?
Last week, I teased you with the idea that it’s actually easy to estimate distances to galaxies. I do mean estimate — and distance indicators are still important. The Hubble Law is named for Edwin Hubble, the astronomer who was…
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Binary Neutron Stars
Way back when we spent a number of posts surveying the stars, we covered binary systems. These are star systems that contain multiple stars. Imagine if our sun had a companion, and two stars rose and set in our sky…
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What are Planetary Nebulae?
Meet the planetary nebula, one of the universe’s most gorgeous phenomena. If you’ve ever looked through a telescope, you may have seen one of these before. Through a small telescope, one might look like a little planet — hence the…
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Spectroscopic Binary Stars
Consider a solar system far different from our own. A solar system governed by two suns, and consisting of planets we can only dream of. Would it surprise you to hear that, based on recent discoveries, that might actually be…
