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What We Really See

In Astronomy by Brian Koberlein4 Comments

When news of the TRAPPIST-1 system blazed across headlines, one of the common questions I got was what the planets really looked like. After all, if we can discover planets around other stars, we surely must be able to see them. But we can’t. In some ways can barely see the star. But this demonstrates how what we actually observe (and what data is important to astronomers) is very different from the common perception of what astronomers observe. Read More

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Doomsday Scenario

In Quantum Mechanics by Brian Koberlein7 Comments

Humans are mortal. Not just as individuals, but also as a species. We can defend against many of the existential dangers to humanity. Threats such as global warming and pollution are well understood, and we can take steps to address them if we have the will. Even cosmic threats such as a civilization ending impact can be mitigated given time. But what about a deeper cosmic threat? What if the Universe could destroy not only our planet, but the entire galaxy, and what if we could never see it coming? Read More

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Is Eris A Brown Dwarf?

In Pseudoscience by Brian Koberlein11 Comments

Yesterday I got an interesting request from a therapist. She works with folks who are terrified that some large object like Nibiru is going to collide with Earth and kill us all, known as cosmophobia. Unfortunately there’s a lot of YouTubers out there that say these fears are quite reasonable, including “a physicist” who claims that Eris is a brown dwarf heading our way. When the therapist presents evidence contradicting the “physicist,” her patients argue that she’s not an expert, and can’t possibly know what the physicist knows. I am “a physicist,” specifically an astrophysicist, so she asked if I would disprove the claim as an expert. So here’s how we know that Eris isn’t a brown dwarf, and isn’t heading our way. By “an astrophysicist.” Read More

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One Ring To Bind Them

In Exoplanets by Brian Koberlein0 Comments

Although our Sun is the only star in our solar system, that isn’t the case for every planetary system. It’s estimated that about than half of stars could be binaries, though the exact percentage is still hotly debated. What we do know is that binary stars are common. This has raised the question about how planets might form in binary systems. Read More

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Dust Bunnies

In Exoplanets by Brian Koberlein2 Comments

On a broad level we understand how planets form quite well. A disk of gas and dust forms around a young star, and clumps within this disk gravitationally collapse into planets. But there are details of this model that still pose challenges. In particular, we don’t entirely understand how small pockets of dust can get large enough to become proto-planets. But new simulations of planet formation are beginning to solve this mystery. Read More

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How To Find A Star System

In Exoplanets by Brian Koberlein1 Comment

There are seven planets orbiting a small dwarf star known as TRAPPIST-1. In 2016, three planets were discovered around the star, and today four more were announced. All of these worlds are roughly the size of Earth, and three are potentially habitable. On its own, TRAPPIST-1 would be easy to overlook. It’s a dim, 18th magnitude star, 40 light years away in the constellation of Aquarius.  So what led astronomers to look for planets around this unassuming star, and how did they find them? Read More

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All In The Family

In Stars by Brian Koberlein3 Comments

When you think of a family tree, you probably think of human ancestry, and how we can trace our ancestors back to different geographical regions. All living things have a common family tree, which can be seen in our genetic code. While stars aren’t living things, they have a similar family tree, and we’re starting to gather enough data to piece it together. Read More