According to NASA’s Exoplanet Archive, scientists succeeded so far to identify more than 4,000 exoplanets. When how those exoplanets behave or where they can be found, we have many possibilities.
Yet, we don’t know exactly why when it comes to their size; there exist some limitations. Why such things occur? Well, it seems that we can put all the blame on physics. For example, in our Solar System, there are two types of planets. First, we have the small, rocky, but dense planets, which can also resemble Earth, and then, there are the gaseous, more massive planets, such as Jupiter.
So, by analyzing information from the Kepler mission or TESS, we can notice a gap in the planet dimensions. Specifically, there aren’t many planets that fill the description of a “super-Earth,” with a limit of one and a half to twice our planet’s range and a volume that is five to 10 times more prominent. Why aren’t there any super-Earths yet? Moreover, why do scientists only identify small edgy planets and massive gaseous planets?
Scientists explain that when a star develops, a giant ball of gas unites, begins to rotate, crashes in on itself, and lights a fusion reaction within the star’s center. Such a thing, however, is not that perfect. There is a lot of additional gas, and dust remained after the star is born. That extra matter goes on in a swirling around the star until it finds its final shape, which is a stellar disk, ring-shaped and flat, contained dust, gas, and rocks.
Size Matters in the Galaxy When It Comes to Planets, Says the New Study
Moreover, as the space object increases, its volume and gravity also boost up, letting it collect not only the rocks and dust but the gas, too.
The gas will ultimately create an atmosphere. Furthermore, within the solar disk, there is a lot of gas, because after all, helium and hydrogen are the most encountered things in stars and in the universe, too. But, there is considerably less solid matter due to a limited quantity that resurfaced during star birth.
A planet, however, needs the precise concentration of gravitational pull and mass, to cease the torrent of gas from accumulating onto the planet and dragging it up. Such a thing is sometimes dubbed as “unstable equilibrium” – when a space object is lightly dismissed, for example, is going farther from the initial state.
Another reason could be that when a planet is created, it doesn’t always keep its position in the same orbit. It’s possible that sometimes, the planets relocate or change its trajectory towards their host star. So, as the space object approaches the star, its atmosphere warms up, resulting in the molecules and atoms to redirect quickly and leave the planet’s gravitational pull. Finally, because there are no supermassive edgy planets or small fuzzy planets, there is still a considerable tremendous volume of variety in planet dimensions, structures, and geometries.