How Massive Stars Die

January 21, 2021November 23, 2022 / Emma / Leave a comment

When people think of star death, they most often think of supernovae (plural for supernova). So why haven’t I spent the past bunch of posts on star death talking about them?

Because supernovae are not actually the most common fate to await a star. Only a small fraction of the stars in our universe are massive enough to go supernova. Most stars die fairly quietly, gently expelling their outer layers and contracting to form white dwarfs.

No such gentle fate awaits the most massive stars.

But why do massive stars go supernova?

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The Solar Neutrino

January 24, 2018November 23, 2022 / Emma / 2 Comments

Ever heard of a neutrino?

Well, I guess now you have. But what exactly is a neutrino?

Don’t worry, they’re not harmful. They’re passing through you this very second and you’ll never notice them, not in your whole life. They’ll never hurt you because they just don’t interact with matter—including you—in the way you’d expect.

I’ll bet now you’re wondering where they even come from.

Well, as the diagram illustrates, they come from the sun. They’re kind of a side-effect of the nuclear reaction that powers the sun, and they radiate out from the sun in droves. But that’s not even the coolest bit.

We know how many neutrinos should come from the sun if our theories about its power generation are right. So if we can count them, we can prove those theories correct.

That’s when we encounter a bit of a problem. We can’t actually detect neutrinos.

So how the heck do we count them?

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The Proton-Proton Chain

October 31, 2017November 23, 2022 / Emma / Leave a comment

Take a wild guess: how much energy do you think the sun generates?

Think about it. It definitely generates enough energy to power a world.

Humans depend on the photosynthesis of plants, which converts sunlight into energy. And that’s not all. Without energy from the sun, our atmosphere would behave very differently, and so would our oceans.

Everything that moves on Planet Earth does so because it has energy. And a lot of that energy comes from the sun. It doesn’t even stop there—obviously, the sun has plenty of energy to spare, if the recent influx of solar power means anything.

The sun is incredibly powerful. And it’s powerful enough to keep generating that kind of massive energy supply for billions of years.

So where does it get all its energy?

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