Lake Toba in Sumatra (pictured above), the largest volcanic structure on Earth, is an example of an enormous caldera that has filled with water over time.
Whereas volcanic craters arise from deep inside the planet, impact craters originate in outer space.
When a meteor makes it through Earth's atmosphere without burning up, it strikes the ground faster than the speed of sound.
"Something we don't understand very well on the geological side (of crater formation) is, we still find it difficult to determine the trajectory of impacting objects for most impact craters," Kring said. "We're still searching for a clue to deduce that."
But no matter at what angle it makes contact, the enormous amount of kinetic energy the projectile carries immediately transfers to the target rock it hits, triggering powerful shock waves.
Although craters look like imprints of a giant fist smashing the ground inward, impact shock waves have the opposite effect, which planetary scientists divide into three phases.
The compression stage of crater formation involves that initial exchange of energy between the projectile and the impact area.