Science: Sunspot Programs

Like a fawn born in spring, television passed its tender youth in a favorable climate. During the past six years, while TV sets were becoming common articles of furniture, the sun had few spots to mess up TV reception. Now sunspots are increasing on their nine-to 13-year cycle, and televiewers are apt to see odd and sometimes annoying effects.

Sunspots are storms in the sun's surface layer of bright, turbulent gas. They send out blasts of radiation and high-speed particles that hit the earth's atmosphere and form ionized (electrified) layers at high altitudes. Ordinary sunlight does this too, but sunspots beef up the layers and make them strong enough to divert TV signals that would normally pass through into outer space.

The effect of this is to make TV pictures show up on distant screens, sometimes thousands of miles away. During the last sunspot maximum, in 1947, programs from London were often received in New York City, and one fan in South Africa reported picking up London. The last sunspot minimum was in April 1954 (sunspot count: 3.4). The curve is now heading up mightily. Last month the count was 90.2, and the maximum is expected to come in about two years.

In 1947 few programs were broadcast, but the world is full of stations now. If the sunspot maximum is a strong one (sometimes they fizzle), programs from almost anywhere are apt to show up almost anywhere else. The pictures will seldom be good, and they will seldom last long. If the foreign station has a different line image (Britain uses 405 lines, the U.S. 525 lines), its picture will be a meaningless pattern of distorting interferences. U.S. viewers in some cases can adjust their sets to pick up the foreign picture, but then they will not get U.S. pictures.

The Western Hemisphere has plenty of 525-line stations, and so have Japan and the Philippines. So the viewer who tunes to an empty channel and waits a long time may see a commercial advertising a sharkproof bathing beach or a group of kimonoed actors performing an ancient Japanese play.