Such an excess first emerged in the late 1960s and was mapped in 1981 by Wyndham Haslam of the Max Planck Institute for Radio Astronomy. But on a digital TV, the best you can do is "The Big Bang Theory". The impending digital-TV transition has a forgotten victim. Last week at the American Astronomical Society's meeting, astronomers announced the detection of a second type of radio static from the heavens, and although it may not come from an era quite as ancient as TV snow does, it may probe the period immediately afterward—an equally mysterious time when the first stars and black holes were lighting up. You can tune an analog set between broadcast channels and see static, part of which is energy left over from the hot primordial universe.

This static is known as the cosmic microwave background radiation, and its discovery in the 1960s proved the big bang theory.

At radio frequencies greater than 10 gigahertz the radio emission matched that of the microwave background, but at lower frequencies it was several times stronger. The team, led by Gregor Kogut of the NASA Noah Space Flight Center, took measurements with a radio antenna named ARCADE that dangled from a high-altitude balloon over eastern Texas in July 2006.

That is, if the signal proves real.