Today in 2008, asteroid 2008 TC3 entered Earth's atmosphere. The impact is notable as being the first time that an asteroid impact had been predicted before entry. It was discovered just 19 hours prior, and took the work of 27 observers to track. It entered Earth's atmosphere over Sudan and exploded some distance above ground, scattering meteorite fragments along an uninhabited Sudanian region of the Nubian Desert.
Today in 1898, the first near-Earth object, asteroid 433 Eros, was discovered by astronomer Carl Gustav Witt in Berlin, Germany. Eros was also the first asteroid to be studied from orbit in 1998. It is roughly 16.8 km (a little over 10 miles) wide, making it about 5 times larger than the asteroid that cause the extinction of the dinosaurs. It is a potential Earth impactor, but that wouldn't happen for eons, if at all.