Geology of solar terrestrial planets billions of years ago in the cores of massive stars. These elements constituted only 0.6% of the material in the solar nebula. That is why the terrestrial planets could not grow very large and could not exert large pull on hydrogen and helium gas. Also, the faster collisions among particles close to the Sun were more destructive on average. Even if the terrestrial planets had had hydrogen and helium, the Sun would have heated the gases and caused them to escape. Hence, solar terrestrial planets such as Mercury, Venus, Earth, and Mars are dense small worlds composed mostly from 2%
Solar System is thought to have been crucial to the Sun's development of a planetary system because the planets form from the accretion of "metals". The vast majority of the Solar System consists of a near-vacuum known as the interplanetary medium. Along with light, the Sun radiates a continuous stream of charged particles (a plasma) known as the solar wind. This stream of particles spreads outwards at roughly 1.5 million kilometres per hour, creating a tenuous atmosphere that permeates the interplanetary medium out to at least 100 AU "(see )". Activity on the Sun's surface, such as solar flares and coronal mass