Formation of Mercury

Mercury is the smallest of all the planets. The formation of the planet mercury still remains a question of debate for the scientists. At present there are two theories regarding the formation of mercury. The first one is the core accretion theory. This theory works effectively as far as the formation of the terrestrial planets are concerned such as Mercury. This theory usually encounters problem with respect to giant planets. Approximately 4.6 billion years ago, the solar system was a cloud of dust and gas known as a solar nebula. With the rise of the sun, the remaining material began to tie up and due to force of gravity the smaller particles gathered together into larger particles. The solar wind took away lighter elements from nearby regions and left only heavy, rocky materials to create smaller terrestrial worlds like Mercury. Similar to our Earth, the metallic core of Mercury formed first, and then gathered lighter elements around it to form its crust and mantle. Mercury, like other planets, likely collected the more nebulous pieces that formed its atmosphere. The second one is the disk instability model. It states that although the core accretion model works fine for terrestrial planets, gas giants would have needed to evolve rapidly to grab hold of the major mass of lighter gases they contain. But simulations have not been able to account for this rapid formation.  The larger objects now tend to scatter the smaller ones more than the smaller ones scatter them back, so the smaller ones end up getting scattered out of the pebble disk. Studies of Mercury reveal that its core is significantly more massive than expected in relation to the rest of the planet. Mercury most likely suffered a violent event early in its life.

By: Anuja Arora

Content: https://www.space.com/18641-mercury-formation.html