Planets in example sentence
This was formed over four billion years ago in the earliest days of the solar system while the planets were still forming.
More example sentences with word planets
And what starts happening is that, around young suns, young stars, all these elements combine, they swirl around, the energy of the star stirs them around, they form particles, they form snowflakes, they form little dust motes, they form rocks, they form asteroids, and eventually, they form planets and moons. 
