Man-Made Comet Tests Impact of Solar Wind : Magnetic Field Experiment Marred by Fire That Destroyed Observation Plane

A man-made comet launched over the Pacific Ocean on Wednesday night was visible from Texas to Peru, and scientists called the experiment a success Thursday, despite a fire that destroyed a NASA observation plane on the ground.

The creation of the artificial comet 74,000 miles above the sea was the last in a $78-million international series of eight experiments designed to study how Earth’s magnetic field is affected by solar wind--an electrically charged gas, or plasma, that speeds from the sun at nearly 1 million m.p.h.

“The theoreticians are having a ball with the data,” project manager Gilbert Ousley said in a telephone interview from the Washington headquarters of the National Aeronautics and Space Administration.

‘Very Good Observations’

Johns Hopkins University researcher Richard McEntire, reached in Baltimore, also deemed the experiment a success. “Some very good observations were made of the comet,” he said.

A West German satellite released two canisters of the metallic element barium at 8:50 p.m. PDT Wednesday over Tahiti. The barium, which illuminated as it was energized by solar wind, formed the artificial comet.

The man-made comet--the second ever launched--measured about 250 miles in diameter and sprouted a tail 4,500 miles long. The latest comet was somewhat smaller than the first, created last Dec. 27, which was not visible to most ground observers because of cloudy weather, Ousley said.

Authorities said four crew members and 15 scientists from the Ames Research Center in Mountain View, Calif., escaped without injury when NASA’s four-engine Convair 990 flying observatory blew a tire and then caught fire as it rolled down the runway at March Air Force Base near Riverside.

The fire was allowed to burn itself out, destroying the equipment-laden plane that was used as a model in the design of the space shuttle.