Scientists found a possible moon nursery around a distant world, which can change what we know about the formation of Earth's only natural satellite

Scientists have been trying to comprehend the moon formation process around giant planets for many decades already. Most theories about this phenomenon were developed based on observations conducted within the Solar System. However, the actual event happened billions of years ago and provides almost no clues now. However, using the latest technologies, specifically, the NASA James Webb Space Telescope, researchers found what might be the most recent example of an environment where moons form.

CT Cha b is an exoplanet located about 625 light years away from Earth. According to researchers, this young, massive planet is surrounded by a circumplanetary disk, a disk of gas and dust surrounding not the star but the planet itself. This finding allows scientists to observe something they rarely see when working with planets. In other words, CT Cha b and its surroundings represent an excellent opportunity to see a modern example of a potential moon-forming environment.

Analysis of the unusual disk


According to the ESA, Webb provided scientists with an opportunity to study the chemical composition and physical characteristics of the disk around CT Cha b. There were seven different compounds that contained carbon found in the disk. This finding is crucial because it implies that the disk is more than just dust that floats around in outer space. The disk contains materials that can be used for the development of future moons.

In addition, NASA underlined the fact that this disk is distinct from the protoplanetary disk around the host star. This is an important finding because researchers sought to verify that what they see is not simply background material from the star's surroundings. This is one of the strongest pieces of evidence for a circumplanetary disk discovered so far, according to the researchers, as stated in the ESA press release.

Moon formation challenges

The issue of moon creation has remained theoretical because researchers cannot observe events from millions of years ago when Earth was created. For example, the Galilean satellites that exist around Jupiter had most probably formed within the disk surrounding the gas giant. However, these conditions do not exist any longer. What does Webb provide to change the situation?

With Webb, researchers have an object to compare their predictions and models based on the existing scientific knowledge to the facts observed. In accordance with NASA, Webb's broader mission also involves studying the evolution of planetary systems, rings, and moons in the universe.

No scientist has ever seen actual moons

But despite all this enthusiasm, researchers remained cautious with regard to the data obtained by the Webb telescope. First of all, the telescope has not discovered any mature moons around CT Cha b. As mentioned above, Webb has only shown the presence of an appropriate environment for future moon formation, which is important because this process takes a lot of time.

Though the disk represents the material out of which moons are supposed to be formed, it remains unclear at this point whether moons begin forming within it and, if yes, what their size is going to be in the future. According to ESA, observations made with the help of Webb represented just a snapshot.

The chemistry could be the biggest clue yet

One of the key elements of the discovery is the role played by chemistry. The molecules of carbon-rich substances discovered by Webb make it easier for researchers to study the types of building blocks found within the disk, which affects the ability of particles to attract each other and form larger bodies. The chemistry, according to specialists, might be used to explain why certain giant planets have a complicated satellite system, while others lack one.

Moreover, an article published in Nature Astronomy suggested that magnetism might play a role in the moon formation within circumplanetary disks. That makes CT Cha b particularly unique. For the first time, scientists get a real chance to test their theories without using only computer simulation to make predictions.

The discovery may set future trends

Experts say the discovery will change the future course of scientific research of satellite formations for many years to come. Instead of asking vague questions about theoretical processes of moon formations, researchers can analyze one observable system, taking into account the available data on its chemistry and organization.

The discovery is also valuable when trying to study the variety of planet systems beyond Earth's. While the formation of Earth's Moon is attributed to a giant impact event, the creation of the larger moons found orbiting Jupiter and Saturn can be explained by their development within circumplanetary disks similar to the one observed by Webb around CT Cha b. This allows for a better perspective on how these moons form.

However, CT Cha b does not seem to be a completely resolved puzzle but rather something that requires further study. Researchers still need time to discover if the disk will form its moons. Nevertheless, the new discovery is certainly a breakthrough. Not only did Webb locate yet another faraway exoplanet, it has also provided the best example discovered so far of where moons could come into being.