The Biggest Star

The Biggest Star

If you’ve ever looked up at the Sun on a summer day and thought, “Wow, that thing is huge,” I’ve got some news for you. Compared to the big leagues, our Sun is basically a tiny marble rolling around under the feet of giants.

Let’s meet the current heavyweight champion: Stephenson 2–18.

Wait, How Big Is It?

Imagine you’re on a road trip. If you got into a plane and flew around our Sun at 500 mph, it would take you about seven months to finish the loop. Not bad, right?

But if you tried to fly around Stephenson 2–18 at that same speed? You’d be in the air for over 1,000 years. You’d literally need 15 generations of your family to finish the flight.

If we swapped our Sun for this monster, it wouldn’t just swallow Earth. It would gulp down Mars, Jupiter, and keep going until it hit Saturn. We wouldn’t just be “too close” to the Sun; we’d be inside of it.

The “Big Mac” of Space

The funniest thing about these stars is that even though they’re massive, they’re surprisingly… fluffy?

Because they’ve stretched themselves out so far, their outer layers are incredibly thin. Scientists call them “Red Supergiants”. But honestly, they’re more like giant cosmic cotton candy. They are huge, red, and glowing. If you tried to grab a handful of the “star” at its edge, there’d be almost nothing there. It’s just a warm, glowing ghost of a sun.

A Bit of 2026 Drama

Here’s the tea: being the “Biggest Star” is a title that changes all the time. Astronomers work hard, so does technology.

Just this year, astronomers have been arguing over whether Stephenson 2–18 is actually as big as we think. Measuring things trillions of miles away is hard! Some people think it’s a bit of an optical illusion, and they’re looking at other stars like WOH G64 as the “real” king.

WOH G64 is actually in a different galaxy! We’ve been watching it lately because it’s started acting a bit “fussy” — puffing out dust and changing its glow like it’s getting ready for a big finale (a supernova).

Why Should We Care?

It’s easy to feel tiny when you talk about this stuff, but here’s the cool part: when these giants eventually “pop,” they sneeze all their guts into space. The iron in your blood and the calcium in your teeth? That stuff was cooked inside a giant star exactly like this billions of years ago.

We’re basically just recycled stardust from the biggest celebrities in the galaxy.

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