The Earth-like planets are similar in size to Earth. However, most of these planets are similar to gaseous bodies in classification.
Mega Earth – Discovery of New Exoplanet
Recently, the astronomers have announced that they have found a new baffling planet outside the solar system. Since this planet doesn’t fit any of the above classifications, so they classified it as “Mega-Earth” exoplanets based on its characteristics.
The new Mega-Earth planet is approximately 560 light-years away from our Earth in the constellation of Draco. Its weight is equal to the combined weight of 17 Earth-sized planets. However, it is merely 2.3 times larger in radius compared to the earth.
This means that the Mega Earth planet is mostly composed of rock and other such heavy compounds. Astronomers have also noticed that there is no such gaseous envelope perplexing in or around the planet.
In one opinion, the baby-stars generate huge protoplanetary disks during the formation of the planetary systems. Due to which, the planetesimals accrete material inside them. This happens until they acquire enough mass to develop and retain layers of gaseous material. This gaseous material creates a remedial atmosphere around the planetary system. Later on, the planetesimals evolve into either gas-giants or terrestrial planets depending on the ratio of gas accreted and rocky material.
According to one of the researchers from the Harvard-Smithsonian Center, it is very difficult to form a large solid planet like Mega Earth without accreting even a small amount of hydrogen and helium. The whole team looked into various scenarios to determine the formation of the Mega Earth planet.
According to one such scenario, they believe that the Kepler-10c was created when two large yet barren terrestrial planets collided with each other during the chaotic first years. This was followed by the birth of the sun-like star planetary system.
They also noted that the star hosts another planet known as the “lava world” or Kepler-10b. The Kepler-10c completes one orbit around its star every 45 days, while the Kepler-10b makes one orbit around the star in just 20 hours.
People usually assume that the universe consists of large, mostly-gaseous bodies with some specific classification. After the discovery of Kepler 10-c planet, the astronomers think that the universe has started churning out the terrestrial planets compared to the gaseous planets. The new Mega Earth planet itself orbits a star which is old enough to achieve enough stability for life to get a solid footing. Before the discovery of the Mega Earth planet, the astronomers used to think that the universe was composed mostly of hydrogen and helium. Now they are of the opinion that the heavier material didn’t pop in until several of the first generations of stars died. Consequently, the interstellar medium seeded with the rocky material which is required for the formation of the terrestrial planets.