How are comets formed?

Comets are fascinating objects that have captivated humans for centuries. These celestial bodies are made up of ice, dust, and gas, and originate from the outer reaches of our solar system. Scientists believe that comets were formed around 4.6 billion years ago during the formation of our solar system.

Comets are thought to have formed in two main regions of the solar system: the Kuiper Belt and the Oort Cloud. The Kuiper Belt is a region beyond Neptune's orbit that contains a large number of icy bodies, including dwarf planets and comets. The Oort Cloud, on the other hand, is a theoretical cloud of icy objects located in the outermost reaches of our solar system.

Comets are formed when the gravity of a planetesimal (a small planetary body) disturbs an icy object in the Kuiper Belt or Oort Cloud, causing it to fall into a highly elliptical orbit around the sun. As the comet gets closer to the sun, the heat causes the ice to sublimate (turn from a solid directly into a gas), releasing dust and gas into space. This process creates the characteristic tail that comets are known for.

Comets are believed to be remnants from the early solar system, and studying them can provide insights into the conditions and processes that occurred during the formation of our solar system. NASA and other space agencies have sent missions to study comets up close, including the Rosetta mission which landed on the surface of comet 67P/Churyumov-Gerasimenko in 2014.