Number 111 (Story #1), January 21, 1993 by Phillip F. Schewe and Ben Stein SQUID DETECTORS OPERATING IN THE MILLIATTOVOLT range have been able to measure a tiny resistance in a YBaCuO thin-film superconductor, even in low magnetic fields and for low currents (F.C. Wellstood et al., 4 Jan. 1993 Physical Review Letters). The resistance arises from noise in magnetic flux lines which do seem to penetrate the sample even though the external fields used are far below the critical field at which penetration is supposed to commence. By the way, although the scientists in this Maryland-AT&T-Berkeley collaboration use the prefix milli-atto to denote 10 raised to the -21st power, the official name for this prefix is "zepto," or just z. For those who would go further yet, the name for 10**-24 is "yocto." (Science News, 16 Jan. 1993.)