Could the Discovery of a New Planet Complete the Solar System?
A new planet may be hiding in the outskirts of the solar system. Planetary scientists predicted its existence based on the odd orbits of far-fling icy bodies. These tiny objects can be found in the distant Kuiper (KY-pur) belt — a wide expanse of space just beyond the orbit of Neptune.
Planet Size and Orbit
Konstantin Batygin and Michael Brown of Caltech in Pasadena, California suggest that this new mystery planet is estimated to be 10 times bigger than the Earth. And if it does exist, it would travel a highly elongated orbit.
Currently referred to as the “Planet Nine”, getting a glimpse of the planet may be difficult because of its distance. And while the astronomers have already identified its orbital path, they have yet to locate exactly where in its orbital cycle it currently is. Brown, Batygin, and their team of scientists are asking the public for help, rather than searching the planet in secrecy. As what Michael Brown said, “I would love to find it. But I’d also be perfectly happy if someone else found it. That is why we’re publishing this paper. We hope that other people are going to get inspired and start searching.”
These planetary scientists feel certain about their discovery, which at first seemed unbelievable to them.
“For the first time in more than 150 years, there’s good evidence that the planetary census of the solar system is incomplete,” said Batygin, referring to the discovery of Neptune as the 8th planet.
As soon as Planet Nine is detected, Brown insists that there will be no debate about whether or not it is a true planet. Its size is big enough; and compared to Pluto, the planet dominates its cosmic neighborhood.
Is it a Super Earth or Mini-Neptune?
Based from what we’ve learned about planet formation and exoplanets population, a world with this mass is more likely to be covered by a deep atmosphere that mainly consists of primordial hydrogen and helium. Since Neptune is estimated to be 17 times the Earth’s mass, the newly-proposed planet is much like a “small” ice-giant planet rather than a “big” rocky planet.
Is it Habitable?
At first glance, you’d think it isn’t. It is very far from the sun that there might only be little solar heat. However, a thick hydrogen atmosphere with high pressure can be impervious to infrared radiation and serves as a good thermal blanket. The original heat from the planet formation might have not yet leaked out from this “Planet Nine” world. Therefore, it is possible that in some of its deep layers, there are conditions where liquid water may exist, making it a world with a dark ocean surface that can be compared to the Earth’s abyssal depths. Whether it could support life, we don’t know yet.
Should it be the 9th Planet or something else?
The classification of the planets should enhance our scientific knowledge; however, history plays a role. If this planetary object formed with other giant worlds, then it could be considered as the 9th major planet.