2 (b.d.)
Rocky objects, called asteroids, are too small and too numerous to be considered full-fledged planets. Most asteroids revolve around the sun between the orbits of Mars and Jupiter. This region of the solar system is called the asteroid belt.
Scientists now hypothesize that the asteroids are leftover pieces of the early solar system that never came together to form a planet.
Some asteroids have very elliptical orbits that bring them closer to the sun than Earth’s orbit. Someday, one of these asteroids could hit Earth. One or more large asteroids did hit Earth about 65 million years ago, filling the atmosphere with dust and smoke and blocking out sunlight around the world. Scientists hypothesize that many species of organisms, including the dinosaurs, became extinct as a result.
Scientists now hypothesize that the asteroids are leftover pieces of the early solar system that never came together to form a planet.
Some asteroids have very elliptical orbits that bring them closer to the sun than Earth’s orbit. Someday, one of these asteroids could hit Earth. One or more large asteroids did hit Earth about 65 million years ago, filling the atmosphere with dust and smoke and blocking out sunlight around the world. Scientists hypothesize that many species of organisms, including the dinosaurs, became extinct as a result.