Astronomy
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The Big Bang in a Nutshell
Okay, okay, I know…with that featured image, I just broke my own cardinal rule of not depicting the Big Bang as an explosion. I did pick that image for a reason, though. We first covered the Big Bang waaaay back…
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Dark Matter: What We Know
I considered titling this post “Dark Matter Demystified” and including it in my “Cosmos Demystified” series…but honestly, there are some promises I can’t make! Dark matter is one of the most mysterious concepts in cosmology, second only to the even…
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What is an Annular Eclipse?
Sept 2024: This post has been updated and republished from Sept 2017. First of all, my apologies for missing the last few weeks of posts. I’ve been completely bogged down with physics homework! (Ironic that I’m missing physics-related posts in…
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Cosmology: How Do We Know?
Have you ever wondered how the heck astronomers think we know anything about cosmology? It’s a truly mind-blowing field of study, full of whacky concepts like the shape of empty space, the expansion of the universe, and dark energy. More…
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The Proof in the Afterglow
In 1915, Einstein published his theory of general relativity. This theory predicts that, since gravity works by bending space-time, it also determines the shape of space — and the shape of the universe as a whole. In 1929, Edwin Hubble…
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The Big Bang Theory, Revised
Imagine a time before stars and galaxies existed, before free-floating subatomic particles combined to form the first atoms, before the synthesis of the first atomic nuclei… Wait a second — this sounds familiar! Way back in May, we rewound the…
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Geometry is Destiny…or is it?
Cosmologists used to think that gravity alone determined the shape of the universe, and that shape, in turn, determined its future. But that raised a lot of problems. Gravity works by curving space-time, so it can also force the fabric…
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The Discovery of Dark Energy
In 1998, astronomers made an extraordinary discovery. Contrary to expectation, the expansion of the universe is accelerating. Astronomers wondered at first if their measurements were wrong; further measurements confirmed the results. And then confirmation of the expansion came in the…
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Should Expanding Space be Slowing Down?
Einstein’s theory of general relativity holds that matter curves the fabric of space-time. That’s how gravity works. In turn, that gravity shapes the fabric of the universe. Depending on how much mass is in the universe, gravitation can curve the…
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Why do Galaxies Exist?
When we look out into the sky, we see a universe filled with galaxies. Galaxies are the second-largest “structure” we’ve covered in depth on this blog. The largest so far have been galaxy clusters, which are just what the name…
