Terrestrial planet are a source of great interest for astronomers, partly due to their potential for harboring life. TOI-849b is particularly intriguing, as it has contains 40 Earths’ worth of matter. It is approximately as large as our own Neptune but contains 2-3x more mass. Why is this interesting? That’s because it is very rare for terrestrial planets to be quite so massive, that’s quality more associated with gas giants (‘giant’ is in the name).
The new planet, only 730 light-years away (not more than a hop, skip, and a jump in astronomical terms), goes even further to differentiate itself from a gas giant, as it barely has any atmosphere to speak of. This has led scientists to speculate wildly as to how such a planet could have been formed.
It seems unlikely that such a planet could have been formed by the ‘conventional’ method of terrestrial planet formation, a process called accretion, where microscopic solid particles coalesce together over a long period of time to form planets. Scientists currently theorize that this giant planet is actually the exposed core of a gas giant, which would have been larger than Jupiter. How the core got exposed and the outer gaseous layers got expelled is a mystery.
If such a planet is indeed capable of harboring life, the magnitude and diversity of its species count could be exponentially more than ours, due to a higher number of resources available that could support more life. It is quite intriguing to wonder whether this increase in available resources could allow more species to reach a level of intelligence that could help them establish civilizations, or if it would just breed a level of competition amongst lower-level species that they would never have the opportunity (or need) to evolve to that degree. This is all just postulation and conjecture, but the human race is one that is built on the urge to find out more about the unknown, and hypothesize and explore until we figure it out.