It's tough to look back to the first stages of the universe. Shockingly enough, the distances involved are astronomical. Billions and billions of light years (and normal years) separate us from the first galaxies, but thanks to telescopes like Hubble, we can look back to something around 400 million years after the Big Bang. But the things we see are on the magnitude of galaxies. Vast cosmic structures, nothing on the order of stars themselves. Well, until now.
Meet Earendil. It's about 50 times bigger than the sun, and while the name is technically Old English, it's probably more familiar to fans of J.R.R. Tolkien. In the Silmarillion, Earendil was a seafarer who carried a silmaril across the sky; he was mentioned in song by Bilbo in Lord of the Rings. I'm going to guess the scientists who named the star were probably thinking Tolkien, not Old English.
Anyway, this star is 12.9 billion years old (roughly), meaning that it formed just 1 billion years after the Big Bang. The previous record for a single star was 4 billion years after the Big Bang, so we're not talking some small, piecemeal improvement; Earendil has absolutely destroyed the record for farthest star. But while this is a big star, it would absolutely not be possible without a bit of luck in the form of gravitational lensing. A massive galaxy cluster sits between us and Earendil, and its gravity has focused the light behind it; we almost literally have a magnifying class pointing at the star.
Since the galaxy cluster will remain in place for years, Earendil will remain a focus for astronomers for quite a while, and the James Webb Telescope will surely participate in its observation as well. Earendil may represent the first known example of a Population III star, or the first stars formed after the Big Bang. We could learn a lot about the formation of those early stars from it. Plus, it's just really cool, spotting a specific star that far away.
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