A new study found that before the birth of the planets in this exoplanet's size and mass, with no reference to their atmospheric conditions or ability to harbor life. The term refers to exoplanets larger than Earth but smaller than Neptune.
Super earths are reportedly reasonably common in the overall scheme of things, and about 30-percent of all sun-like stars in this galaxy are said to have them in their solar systems. However, there's none in this solar system, which has baffled researchers for a long time. The latest research seems to have solved that mystery. The study's authors believe that those rings around the sun billions of years ago are to blame for the lack of a super-earth in this solar system.
The study was conducted by astrophysicist André Izidoro and his colleagues at Rice University, the University of Bordeaux, Southwest Research Institute in Boulder, Colorado, and the Max Planck Institute for Astronomy in Heidelberg, . They created a computer simulation model of the solar system's formation, which suggested that billions of years before the birth of the planets, the sun was surrounded by high-pressure regions of gas and dust, described as "pressure bumps in the sun's protoplanetary disk." These rings eventually went on to form the planets and could answer why this solar system does not have a super-earth.
Three Distinct 'Pressure Bumps'
According to the model, three such bands of pressure bumps decided how the planets were formed in those regions. As explained by the report, these high-pressure areas were formed when the sun's gravitational pull drew in the particles in these three rings and vaporized them with the heat in a process called sublimation. In the ring closest to the sun, solid silicate turned into gas, while in the middle ring, ice heated up to form water vapor. Finally, in the last ring, carbon monoxide became a gas.
All the three rings trapped dust that accumulated into "asteroid-sized planetesimals," which went on to form the planets as they exist today. However, the chemical composition of the planetesimals varied based on which ring they originated from. According to the study, the ring closest to the sun was instrumental in forming the inner solar system planets, including Mercury, Venus, Earth and Mars. The second layer was responsible for creating the outer solar system planets. The final layer eventually formed the Kuiper Belt.
What's most important here, according to the researchers, is the timing of the formation of the middle ring. The model suggests that super earths would have become a reality in this solar system if it had been formed any later than it did. In fact, Mars itself could have been one of those massive planets with ten times the mass of earth, as some models suggested. However, the perfect timing in the formation of the middle ring prevented the creation of super earths in this solar system.
Source: Nature, Rice University