298 Baptistina
A 2007 US-Czech study decided that 298 Baptistina may be the biggest remnant of a 170 km (110 mile) asteroid that was destroyed about 160 million years ago in an impact with a smaller body, making the Baptistina family of asteroids and that the Baptistina event may have created the eventual impact asteroid believed by many to have caused the K/T extinction event about 65 million years ago. This is the K/T impactor believed to be shown in the geological record. This theory has not, as yet, found general acceptance among the scientific community.