Chicxulub impactor Chicxulub impactor The Chicxulub impactor ( ), also known as the K/Pg impactor and (more speculatively) as the Chicxulub asteroid, was an asteroid or other celestial body some in diameter which struck the Earth at the end of the Cretaceous period, approximately 66 million years ago, creating the Chicxulub crater. It impacted a few miles from the present-day town of Chicxulub in Mexico, after which the impactor and its crater are named. Because the estimated date of the object's impact and the Cretaceous–Paleogene boundary (K–Pg boundary) coincide, there is a scientific consensus that its impact was the Cretaceous–Paleogene extinction event
Impact crater central uplift is not the result of "elastic rebound", which is a process in which a material with elastic strength attempts to return to its original geometry; rather the collapse is a process in which a material with little or no strength attempts to return to a state of gravitational equilibrium. Complex craters have uplifted centers, and they have typically broad flat shallow crater floors, and terraced walls. At the largest sizes, one or more exterior or interior rings may appear, and the structure may be labeled an "impact basin" rather than an impact crater. Complex-crater morphology on rocky planets