The Hubble telescope has been searching the heavens for decades, finding one amazing discovery after another. This time, it appears to have found a surprising new example of a Hot Jupiter exoplanet, complete with a stratosphere. What is perhaps even more important, is that the team found signatures of water around that planet.
This Hot Jupiter Exoplanet has a Cooler Interior
The planet is a gas giant about 880 light years from Earth, known as WASP-121b. It was noted to orbit very close to its parent star, completing a revolution every 1.3 days. It is called a hot Jupiter exoplanet because, while it is of similar size to our own king of planets, its upper atmosphere reaches temperatures of 2,500 degrees Celsius or 4,500 degrees Fahrenheit.
One of the most interesting inferences made by this discovery is that this planet seems to get cooler as you head toward the interior. The outer layers of the stratosphere are highly excited, probably from the intense solar radiation the planet receives. That is how the water signatures were discovered.
“The question [about] whether stratospheres do or do not form in hot Jupiters,” said mission leader, Thomas Evans from the University of Exeter, “has been one of the major outstanding questions in exoplanet research since at least the early 2000s. Currently, our understanding of exoplanet atmospheres is pretty basic and limited. Every new piece of information that we are able to get represents a significant step forward.”
That is another exciting part of this discovery, the knowledge that we can determine atmosphere compositions of distant exoplanets. Hubble was able to examine the various spectra of light off of the planet to gauge what elements surround it. Science has yet to develop the technology needed for exploring smaller, rocky bodies like Earth and Mars, but the team has no doubt that future astronomers will develop the techniques and tools.
Image Credits: NASA