Theoretical models of comet formation

Theoretical models of comet formation suggest they originated in the early solar system from a vast, cold cloud of gas and dust. Over time, particles stuck together, forming icy planetesimals in the outer regions beyond Neptune. These icy bodies, called comets, grew through accretion, preserving ancient material. Some models propose that comets are remnants of the primordial solar nebula, while others suggest they formed in specific zones with unique composition. When perturbed by gravitational interactions, comets are sent into the inner solar system, where their icy nuclei develop glowing comas and tails as they heat up from the Sun.