accretion disk
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Active Galaxies Demystified
Active galaxies are, without a doubt, absolutely spectacular. Though rare, they tell a critical part of the story of galaxies — and of the universe as a whole. And we’ve spent the last few posts exploring them in depth. But…
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How Supermassive Black Holes Work
We first took a peek at supermassive black holes back in our discussion of galaxies. But now that we’ve covered a few types of active galaxies, it’s time to take a deeper dive. Okay, I guess we won’t really be…
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How to Find a Black Hole
Okay, good question. How the heck do you find an object that emits no radiation? Astronomers find — and study — just about everything in the universe using the radiation it emits or reflects. So…what happens when the object we’re…
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Black Holes: What the Movies Get Wrong
Any of you recognize this? To those who don’t, it probably looks like a pretty unimpressive, blurry ring. In fact, this is the first ever image of a black hole, taken with an interferometer the size of the Earth. If…
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What is a Black Hole, Really?
If you’re a sci-fi fan, you’ve probably seen these in movies. And I’m guessing you’ve heard a lot about them in pop culture. The problem is, pop culture and movies don’t do a very good job of describing black holes.…
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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 About Binary Systems?
In the constellation of Perseus, there is a star named Algol that exists in a binary system. The binary consists of two stars: a massive main-sequence star and a less massive giant. According to what we’ve explored so far…that doesn’t…
