* Astronomy

The 1400 metre wide asteroid Castalia will make a close pass (44.2 lunar distances, 0.1135 AU), travelling at 12.06 km/second, to the Earth-Moon system on the 28th August, 2012 @ 17:06 UT ±00:01. 

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The Lunar Distance (LD), the distance between Earth and the Moon, equals 384,401 km, (or 0.00256 AU).

The asteroid 4769 Castalia (previously known by the provisional designation 1989 PB) was the first asteroid to be modelled by radar imaging. It is an Apollo, Mars- and Venus-crosser asteroid. It was discovered on August 9, 1989, by Eleanor F. Helin (Caltech) on photographic plates taken at Palomar Observatory. It is named after Castalia, a nymph in Greek mythology. 
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