The asteroid, known as 2009 DD45, came relatively close to the Earth at 8:44 AM EST on Monday:
“The gap was just 44,750 miles; a fifth of the distance between our planet and the Moon; …or only twice the altitude of satellites in geosynchronous orbit. […]
It is in the same size range as a rock which exploded over Siberia in 1908 with the force of 1,000 atomic bombs.”
And how soon did they discover it?! SATURDAY; ie, TWO DAYS NOTICE. To be fair, it may not have been a direct impact – it could have just grazed the surface. And for bullet wounds, at least, grazing is totally what you want to wish for.