Earth is constantly bombarded by fragments of rock and ice, also known as meteoroids, from outer space. Most of the meteoroids are as tiny as grains of sand and small pebbles, and they completely burn up high in the atmosphere. You can see meteoroids larger than a golf ball when they light up as meteors or shooting stars on a dark, clear night. Earth is constantly bombarded by fragments of rock and ice, also known as meteoroids, from outer space. Most of the meteoroids are as tiny as grains of sand and small pebbles, and they completely burn up high in the atmosphere. You can see meteoroids larger than a golf ball when they light up as meteors or shooting stars on a dark, clear night. Planetary Sciences Phys.org – latest science and technology news stories