Latest News About How Big Was The Asteroid That Killed Dinosaurs

Direct answer: Most scientists estimate the asteroid that contributed to the dinosaur extinction was about 10–15 kilometers (6–9 miles) in diameter, with the impact creating the Chicxulub crater roughly 180 kilometers (112 miles) across. Some sources note the impact was a major driver of the mass extinction, though later work also considers possible additional impacts around the same time.[3][7][10]

Latest context

• Size estimates for the Chicxulub impactor commonly cited in recent summaries fall in the 10–15 km range. This reflects crater and ejecta evidence used to back-calculate the asteroid’s diameter.[7]
• The Chicxulub crater itself is about 180 km in diameter, which aligns with the scale of global environmental consequences observed at the K–Pg boundary.[7]
• Some outlets in 2020s reporting discuss additional perspectives, including hypotheses about a second asteroid contributing to the event, though the 10–15 km estimate for the primary impactor remains the standard benchmark in many educational sources.[10]

Illustration

• Analogy: An object the size of Manhattan (roughly 10–15 km across) hitting Earth would deposit energy enough to punch a crater around 180 km wide and trigger global climate effects.

Notes on uncertainty

• The precise origin and exact size are refined as new data emerge from crater analysis, spherule layers, and isotope records; the 10–15 km range remains the widely cited working estimate among scientists.[6][7]

Citations

• The commonly cited asteroid size (10–15 km) and the 180 km Chicxulub crater are described in Britannica’s synopsis of the event.[7]
• Additional reporting and historical summaries corroborate the same size range and crater dimensions.[3]
• Broader discussion of the event's context and related findings appear in Space.com and other science outlets cited here.[6][10]