zlacker

"first detected", meaning this asteroid wasn't detected before. They don't claim anything about earlier detection of other asteroids.

>>kvdvee+(OP)
They do claim that this asteroid is somehow unique.

The best I can guess is that 8 of these have been detected before they hit, but only this one was detected 3 hours before it did. The rest must have been detected with longer or shorter times before impact (presumably longer).

Alternatively, perhaps it is unique because of its small size, at only 1 meter.