Lilley Calls Venus Shot Successful; Mariner II Measures Temperature

Edward Lilley, associate professor of Astronomy, who helped design the Venus Mariner II spacecraft, yesterday explained and evaluated the experiment.

"We are very pleased with the quality of the data," Lilley stated, but said he could not discuss scientific findings yet.

The space craft was launched Aug. 17 from Cape Canaveral. It took 109 days for the craft to come within the required 21,000 miles of Venus, where it recorded data for 40 minutes.

Measured Temperature

"The main objective of the experiment," Lilley explained, is the measurement of the temperature of the surface of the planet on the night side, along the path separating day and night, and on the sunlit side."

The experimental equipment consisted of two radio telescopes attached to the craft operating at very short radio wave lengths. The scientists were able to receive measurements made on the space craft giving them progress checks on the behavior of the telescopes on the cruise toward Venus.

Lilley working with three other scientists, helped make the first plans for the radio telescopes in June 1960 at the Jet Propulsion Laboratories in Pasadena, Calif. The scientific instruments and the spacecraft were assembled in California and then taken to Cape Canaveral to be tested. The final decision on the type of radio telescopes to use was made there.

First Try Failed

The first probe, sent up a few weeks, prior to Aug. 27, was a failure and had to be destroyed after launching.

The second probe, Mariner II, was entirely successful and arrived at Venus last Friday. The measurements of Venus were radioed to tracking stations in, California. Lilley, in Cambridge, was able to listen to a "moment-by-moment account" of the craft's performance over the phone.

This "fly-by mission," as Lilley called it, is the first successful attempt by any nation to obtain measurements of another planet. Lilley stated that "we are looking forward to repeating the experiment in 1964."

The analysis of the data should take one to three months. After it is completed, it will all be published.

Besides recording temperatures the probe may also disclose the presence of water vapor on Venus.