Media_httpdyimgcomapap20090827captb888c76b74f74421ad227dc0057e372dnetherlandsnotmoonrockams101jpgx213y191xc1yc1wc409hc367q85sigfdomezf2xg89o5iphig_umngedcmgzbbvac

It's not green cheese, but it might as well be.

The Dutch national museum said Thursday that one of its prized possessions, a rock supposedly brought back from the moon by U.S. astronauts, is just a piece of petrified wood.