The Most Distant Known Star in the Universe is Named After a Tolkien Character – Here’s Why

Earlier this year, a team of astronomers at Johns Hopkins University led by Brian Welch, a PhD candidate, discovered the most distant known star ever recorded† While the discovery itself is incredible, and has been widely reported on for the past month and a half, there was one thing in particular that caught my attention: the star is named after a character from JRR Tolkien’s The Silmarillion. There’s a reason for that. But first, it’s important to discuss how the star — named “Earendel” — was actually discovered.

The first thing to know about Earendel is that its light takes approximately 12.9 billion years to reach Earth. To put this into context: the previous record-holder, Icarus, takes 9.4 billion years. The difference between those two figures is equal to over 75% of the Earth’s lifetime — it is unimaginably colossal.

“This large jump in distance is likely a coincidence. Finding gravitationally lensed stars is still a fairly new thing, so not many people are actively looking. I was focusing on some highly magnified distant galaxies, so I happened to find an extremely magnified distant star,” Welch tells IGN, referring to the effect that occurs when light traveling through space that has been distorted by a massive object.

At the time of discovery, he was studying the Sunrise Arc, which is the galaxy Earendel calls home. For some reason, all of his research kept predicting a single point here while he was working from an office in his basement back in 2020 — two years later, Earendel was revealed to the world.

An image of Earendel, as well as the gravitational lensing effect that helped its discovery.  (Image credit: NASA, ESA, Brian Welch (JHU), Dan Coe (STScI); Image processing: NASA, ESA, Alyssa Pagan (STScI))

An image of Earendel, as well as the gravitational lensing effect that helped its discovery. (Image credit: NASA, ESA, Brian Welch (JHU), Dan Coe (STScI); Image processing: NASA, ESA, Alyssa Pagan (STScI))

“Tolkien’s character Eärendil was definitely the original inspiration for the name,” Welch confirms. “Once we were reasonably sure this object was a star, I started brainstorming possible names. Eärendil was one of the first things to come to mind, since he ends up sailing his ship Vingilot through the heavens with the Silmaril on his brow, becoming a star and a symbol of hope over Middle-earth.

“As I looked into it further, I found that Tolkien’s original inspiration for the character was an Old English word Earendel, meaning Morning Star, which appears in a poem entitled Crist — ‘Eala Earendel, engla beorhtast. Ofer Middangeard monnum sent.’ ‘Hail Earendel, brightest of angels. Sent to men about Middle-earth.’ The ‘morning star’ reference worked particularly well, since this is a time period often referred to as Cosmic Dawn, so that kind of sealed the deal for me. And the Old English morning star reference was enough to convince my less Tolkien-savvy co-authors that the name worked well.”

As for Earendel itself, there are a few things we already know for sure about it. The distance between it and Earth was determined using the redshift, which refers to the phenomenon of light becoming stretched to longer, redder wavelengths as the universe continues to expand. We also know it weighs in at a mass that’s approximately 50 times greater than that of the Sun, which it shines 1 million to 10 million times brighter than. In the future, scientists will be able to decipher what the star is actually made of, which is of particular interest when you consider that its discovery has pulled us slightly closer toward being able to view the very first generation of stars — another detail that makes its “Morning Star” moniker particularly apt.

According to Welch, this opens up a new way to study the distant universe. Astronomers already hypothesised it would eventually be possible to locate the earliest generation of stars to have formed, but this discovery validates that idea. For the first time ever, astrophysicists will be able to explore stars from when conditions were much different to what we see in the Milky Way and its neighboring galaxies today.

“Tolkien’s character Eärendil was definitely the original inspiration for the name.”

“So far, all we know of the first generation stars (often referred to as Population III stars) comes from theoretical models and simulations,” Welch says. “We don’t have any observations yet to compare these models to. If we can find Pop III stars, we can finally start testing our theories and figuring out how these stars, which are predicted to form out of only primordial hydrogen and helium, differ from the average stars we see today.

“These stars are the forges that create many of the heavier elements that end up forming the building blocks for new generations of stars, planets, and eventually us people, so figuring out how the first stars form these heavier elements gives us more insight into how we came to be.”

All of this testifies to how critical Welch’s discovery truly is — by proving that the universe’s oldest stars are within our reach, it brings us much closer to being able to determine how and why we’re here today. Welch is quick to point out that gravitational lensing is not new — people have been looking at gravitationally lensed galaxies for decades, and the theoretical predictions of gravitational lensing have been around since Einstein’s theory of General Relativity. What is new — and what Welch has proved is worthwhile — is the practice of looking for gravitationally lensed stars in distant galaxies, which have been predicted for ages, but weren’t properly discovered until 2018.

“We expect to see many such galaxies with JWST (James Webb Space Telescope) and other future telescopes, so the odds of finding more extremely magnified stars in the early universe are actually pretty good,” Welch says. “Personally, I expect Earendel’s distance record to fall within the first few years of JWST observations.”

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