Astronomers have been perplexed for years by a mysterious, cloud-covered planet that turns out to be less hot than anticipated and pleasantly shiny.
According to a recent research published in the journal Nature, that is what the James Webb Space Telescope observed when it looked at a so-called mini-Neptune that scientists have been trying to explain ever since it was initially identified near another star more than ten years ago.
This planet, GJ 1214b, is unlike any other planet in our solar system. It is larger than rocky planets like Earth but smaller than any ice or gas giants in our solar system.
Despite this, research indicates that these planets, also known as super-Earths or mini-Neptunes, are extraordinarily prevalent in our galaxy.
Is it comparable to an enlarged Earth? Is it a diminutive, smaller Neptune? Eliza Kempton, an astronomer at the University of Maryland, College Park, wonders if it could be something completely new that we have never seen before, such as a water world where the atmosphere would be steamy.
She claims that GJ 1214b has drawn the attention of scientists since it is the easiest planet of this type to observe. It revolves around a small, brilliant star that is only 48 light-years away and is reasonably close by.
The problem is that the planet has shown to be extraordinarily resistant to disclosing its secrets.
“Living on this planet has been difficult. We’ve been attempting to comprehend the composition of its atmosphere for a very long time,” says Kempton.
She says that seeing a planet as it passes in front of its star and examining the starlight that enters its atmosphere can sometimes reveal information about the planet. The planet is entirely shrouded in a thick veil of clouds or haze, so that tactic didn’t work for this one.
However, astronomers have been able to view this planet in a new way thanks to the recently launched James Webb Space Telescope. This telescope picks up infrared light, which is essentially heat.
Kempton explains that his team’s goal was to observe the heat emanating from the planet, and they were highly effective in doing so.
The planet orbits its star once every 38 hours, as observed by the telescope. According to Kempton, “We were able to successfully map out the temperature of the planet on all of its different phases.”
The dayside of the planet has a temperature of roughly 530 degrees Fahrenheit, which is still far lower than the researchers had anticipated but way too hot for any known life.
That implies that this planet must be highly reflective and able to scatter back roughly half of the incoming energy, rather than absorbing all of the energy emanating from its star.
“We didn’t expect the planet to be so reflective, and we actually kind of expected the opposite,” claims Kempton.
She claims that despite all the light reflection, scientists had previously hypothesized that the clouds might be composed of a dark, sooty haze.
She continues, “That tells us something about what these clouds or hazes in the atmosphere are made of, and that’s really the new big question now,” adding that researchers will probably start attempting to produce chemical hazes in the lab with comparable features to determine what might be going on.
The telescope also discovered evidence of water vapor and methane, indicating the planet is more than just a smaller version of Neptune and that its atmosphere is not hydrogen-rich.
Kempton asserts, “We’re pretty confident there is water there,” adding that the planet is too hot for water to exist as a liquid.
More planets in this size range should be observed by the James Webb Space Telescope, according to her, in order to determine if this one is an anomaly or genuinely representative of this class of planets.
The Max Planck Institute for Astronomy in Germany’s Laura Kreidberg, who wasn’t a part of this research team but has previously used the Hubble Space Telescope to peer at GJ 1214b, was fascinated by the new discoveries.
She referred to this planet as the “white whale” for researchers who focus on worlds outside of our solar system because it has proven to be so challenging to describe.
It’s wonderful to see some of the mysteries finally come to light, adds Kreidberg. “I definitely didn’t anticipate the air to be so sparkly. That was not at all on my radar.
She continues, “We’re going to have to start from scratch to figure out why the world is so shiny.
She claims that it appears as though this is a completely different kind of world.
According to what we’re seeing, it resembles Neptune more than Earth, but it really is a unique entity, she claims. “The atmosphere of Neptune is primarily composed of hydrogen. It appears that GJ 1214b may have a predominantly water-based atmosphere.
As a result, this planet is placed in “a category of its own in a way that was never certain before,” according to Kreidberg. Thus, the planets we are seeing fit into a new, intermediate group.
She finds it “quite strange that the solar system doesn’t have one” given how prevalent they are throughout the galaxy.
