Long description

The figure has three parts. Each part is comprised of two stages: formation and output. In part (a), in the formation stage, two hemispheres with common centres are shown on two sides of a vertical line. The left side of the line is labelled ‘core formation by solid accretion’. Two identical smaller spheres are drawn on the left side of the left hemisphere. An arrow from each of the smaller spheres points towards the centre of the left hemisphere. The right side of the line is labelled ‘gas accretion beyond critical mass’. The hemisphere on the right is bigger in size. A blue ring is shown around the right hemisphere. A set of radial arrows points towards the ring around the right hemisphere. In the output stage, a photo of Jupiter (a gas giant) is shown. In part (b), in the formation stage, a similar diagram to that in part (a) is shown. The left side of the line is labelled ‘core formation by solid accretion’. The right side of the line is labelled ‘slow core accretion’. Here, the blue ring is thinner compared with part (a) and there are fewer radial arrows. In the output stage, a photo of Neptune (an ice giant) is shown. In part (c), in the formation stage, another similar diagram is shown. The left side of the line is labelled ‘core formation by solid accretion’. The right side of the line is labelled ‘growth in the region of the disc with little solids’. Here, both hemispheres are of the same size. The blue ring is far thinner compared with parts (a) and (b), and surrounds both hemispheres. In the output stage, a photo of Earth (a terrestrial planet) is shown.