Catherine Corrigan Catherine Corrigan Catherine Margaret Corrigan (born 1972), often known as Cari Corrigan, is an American scientist best known as a curator of the meteorite collection at the Smithsonian Institution. She is a scientist in the Department of Mineral Science at the National Museum of Natural History. Corrigan obtained a Bachelor of Science in 1995 and a Master of Science in 1998, both in Geology at Michigan State University. Her master's thesis was titled "The Composition of Impact Breccias from the Chicxulub Impact Crater, Yucatan Peninsula, Yucatan, Mexico". She later earned a Ph.D in Planetary Science at Case Western Reserve University
Chicxulub crater is the larger Shiva crater, though the structure's status as an impact crater is contested. The collision of Comet Shoemaker–Levy 9 with Jupiter in 1994 demonstrated that gravitational interactions can fragment a comet, giving rise to many impacts over a period of a few days if the comet should collide with a planet. Comets undergo gravitational interactions with the gas giants, and similar disruptions and collisions are very likely to have occurred in the past. This scenario may have occurred on Earth at the end of the Cretaceous, though Shiva and the Chicxulub craters might have been formed 300,000 years