James Webb Space Telescope discovers first of its kind planet as scientists ask 'what else is out there'

Scientists using the $10 billion James Webb Space Telescope have been left in a state of shock after discovering a first of its kind planet.

With nothing else like it known in the universe, it is a remarkable discovery by the team from the University of Michigan (UoM) in the United States.

It is the latest discovery using the James Webb Space Telescope (JWST), which continues to produce incredible discoveries about the hidden wonders of space.

Looking in to the telescope's findings, UoM undergraduate Eshan Raul came across the discovery in the data. She said: "This is the first time we’re ever seeing something like this.

"The planet appears to be made mostly of hot water vapour, making it something we’re calling a 'steam world'."

Naming the planet GJ 9827 d, it is around twice the size of Earth.

For years, astronomers had thought these kind of 'steam worlds' existed. They simply hadn't been able to prove so until now.

CGI of the 'steam planet' and its nearby star (NASA, ESA, Leah Hustak (STScI), Ralf Crawford (STScI))

And for those interested in all things extraterrestrial, calm down. GJ 9827 d, which is 100 light years from Earth, cannot host life as we know it. But its unique atmosphere opens new possibilities for studying other small planets and their potential to host life, the UoM team says.

To date, almost all exoplanets with measured atmospheres are mainly made of the lightest elements — hydrogen and helium — like the gas giants Jupiter and Saturn in our solar system, Piaulet-Ghorayeb said.

That is, they’re markedly different from Earth’s life-enabling environment.

“GJ 9827 d is the first planet where we detect an atmosphere rich in heavy molecules like the terrestrial planets of the solar system,” says Caroline Piaulet-Ghorayeb, from the University of Montréal’s Trottier Institute for Research on Exoplanets, who has led the study.

“This is a huge step.”

Illustration of the James Webb Space Telescope floating through space (JPL / NASA)

If it wasn't for the JWST, these finds simply couldn't happen, the researchers said.

UoM astrophysicist and NASA Sagan Fellow, Ryan MacDonald, said: "Even with JWST’s early observations in 2022, researchers were discovering new insights into the atmospheres of distant gas giants.

"Now we’re finally pushing down into what these mysterious worlds with sizes between Earth and Neptune, for which we don’t have an example in our own solar system, are actually made of.

"This is a crucial proving step towards detecting atmospheres on habitable exoplanets in the years to come."

The James Webb Space Telescope being constructed before launching in to the cosmos (NASA/Desiree Stover)

Being one of the very first people to see evidence of steam worlds, Raul said: "It was a very surreal moment.

"We were searching specifically for water worlds because it was hypothesised that they could exist. If these are real, it really makes you wonder what else could be out there."