Faraway from Earth in the Sunrise Arc galaxy lies a star so distant that it took 12.9 billion years for its light to reach our planet. Named Earendel, after a character from J.R.R Tolkien’s Silmarillion, this star is the most distant ever observed by scientists and is now a mind-boggling 28 billion light years from Earth.
An Astonishing Star Discovery
Earendel dates back to the first billion years after the big bang, offering researchers a glimpse of stars from this time in the Universe’s history. There was a whole lot of serendipity involved in this particular discovery, says Brian Welch, an astronomer at the University of Maryland/NASA Goddard Space Flight Center, who was part of the team that spotted the distant star in 2022 using the Hubble telescope.
“Typically, galaxies that we see at this distance look like faint little dots,” he says.
But a massive galaxy cluster named WHL0135-08 in the path of Earendel bends and warps its light, creating a magnifying effect that enables scientists to not only glimpse the star but tease out details about it. That’s a technique called gravitational lensing and researchers have used it for decades to make astonishing discoveries.
“The extra boost from the gravitational lensing has been really exciting to be able to sort of peer inside one of these galaxies and see down to the level of these individual stars,” Welch says.
The Details of Earendel
Following Earendel’s discovery, researchers have used the James Webb Space Telescope (JWST) to continue parsing out details. The star is a massive B-type star, around 50 times the size of our own sun and likely about twice as hot.
Researchers believe that this star may also have a smaller, redder companion star nearby, something that Welch says the team had hypothesized at the outset when the first found it.
“Typically, when we see stars that massive in the nearby universe, they have companions,” he explains. “When we got the [JWST] data, it turned out that was exactly what we saw. [There are] really clear signatures of two components.”
“We're trying to really pin down what type of star we're looking at,” Welch adds. “What kind of extra features it has, how many metals, how strong the winds are, the mass and the origin of the star as much as we can.”
Read More: 19 Stunning Galaxy Images from the James Webb Space Telescope
Furthest Exoplanets
When it comes to planets, Neptune is of course the furthest planet from Earth in our own solar system. This gas giant is nearly three billion miles away. But scientists have found planets way beyond our own solar system.
Known as exoplanets, these make Neptune seem close indeed. The closest exoplanet – called Proxima Centauri b – is four light years away, or 24 trillion miles. NASA helpfully explains that if we were to hop on a flight there, it would take 5 million years to arrive.
Researchers have thus far discovered around 5,000 weird and wonderful exoplanets. Kepler-7b for example, is a large, hot version of our own solar system’s Jupiter. The first exoplanet to have its cloud system mapped, researchers made the startling discovery that it has the same density as Styrofoam. Other exoplanets are just as strange, such as Kepler-16b with its two suns, and KELT-9b, a planet so hot that surface temperatures reach as high as 4,327 degrees Celsius (or 7,820 degrees Fahrenheit); that’s hotter than some stars.
Read More: Space Telescope Begins To Reveal the Secrets of Exoplanet Atmospheres
The Most Distant Exoplanet
But taking the title as the most distant exoplanet discovered thus far is OGLE-2005-BLG-390Lb at a stunning 21,526 light years from Earth. Mercifully, this exoplanet is also known as Hoth, a nod to the ice planet from the Star Wars franchise.
Due to the dimness and distance to its nearby red dwarf star – around three times the distance between Earth and the Sun – it’s believed the surface temperature of the exoplanet may be as low as minus 220 degrees Celius (or 364 degrees Fahrenheit), making it the coolest exoplanet discovered and not just because of its nickname.
Scientists used gravitational lensing to discover Hoth near the centre of the Milky Way back in 2005. With a mass around five times that of Earth, it takes around 9 years to complete one orbit of its star. Scientists believe that it may have a thin layer of atmosphere, similar to Earth. But its frigid conditions means that if it does have a rocky surface, it’s probably buried underneath thick frozen layers.
In the vastness of the universe many more exciting discoveries remain to be found from scientists that work with the Hubble and James Webb telescopes, says Welch, as the Roman Space Telescope and Euclid mission peer deeper into space.
“As those observatories start cranking out loads and loads of data, we'll be able to get really high-resolution images over a much broader area of the sky and be able to cover a lot more galaxy clusters in a lot less time,” he says.
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
NASA. New Images From Euclid Mission Reveal Wide View of the Dark Universe
NASA. Earendel
NASA. ESO Discovers Earth-Size Planet in Habitable Zone of Nearest Star
NASA. The King of Gas Giants
Sean Mowbray is a freelance writer based in Scotland. He covers the environment, archaeology, and general science topics. His work has also appeared in outlets such as Mongabay, New Scientist, Hakai Magazine, Ancient History Magazine, and others.
