Near Jupiter, Voyager 2 Uncovers Surprises

PASADENA Calif., July 9 — Voyager 2 streaked within 404,000 miles of the planet Jupiter today, sending back a flood of scientific data and stunning photographs of the planet, and then trained its cameras on Jupiter's mysterious neiehbor satellite. Io.

After a cosmic odyssey that begin at Cape Canavera123 months ago, the 1,800‐pound craft, the sister ship of a similar probe that passed Jupiter in March and uncovered a wealth of surprises about the huge planet, made its closest approach to Jupiter at 6:29 P.M. Eastern daylight time after gliding past three of its nearest satellites, Ganymede, Europa and Amalthea.

Scientists said that Voyager 2 sent dozens of photos Jupiter's Great Red spot, which they said they would assemble into a richly detailed mosaic of the planet's most familiar feature, scores of other photos and thousands scientific measurements back to earth, more than 570 million miles away, as it passed by Jupiter.

Then, accelerated by the powerful gravitational pull the planet, the spacecraft zoomed past Jupiter and flew by To for an attempt to photograph eruptions of volcanoes on the satellite that were detected by Voyager 1 four months ago. A preliminary analysis of early photos from the Io flyby indicated the eruptions were being captured by the Voyager's instruments.

‘Unbelievable Beauty and Mystery’

“We found the Jovian system to be a place of unbelievable beauty and mystery,” Rodney A. Mills, the National Aeronautics and Space Administration's Voyager program manager, said after the fly‐by had been confirmed, “but you wouldn't want to stop there.”

Jupiter, he said, served today as a kind of “filling station: We filled up with energy there.” Ву using the planet's gravity, he said the spacecraft's speed had been doubled more than 95,000 miles an hour and this gave it a push toward Saturn.

“I believe there will be equally great things happening at Saturn,” Mr. Mills said.

Thе mission was directed from the NASA's Jet Propulsion Laboratory here, where scientists, after viewing television images sent back by the craft, said Voyager was continuing to provide them with new surprises about interplanetary space.

“Some, months ago, before Voyager 1, we thought we had some idea of what planets were like,” Laurence A. Soderblom of the United States Geological Survey told newsmen today after reviewing photos of Europa, Jupiter's huge moon, that were made by the Voyager 2 cameras.

Voyager Continues to Yield the Unexpected

Examination of the photos, he said, had been expected to show a sphere heavily pockmarked with the evidence craters left by meteors in the past, much like the moon and Mars are marked. But, he said, the area photographed by Voyager 2 was seemingly as smooth as a billiard ball. There were virtually no craters and the surface was apparently covered with a soft, possibly slushy snow.

The absence of larger craters and, indeed, of virtually any significant topographic relief, researchers said, suggests that Europa might be a relatively young satellite without a long history of meteor impact, although they said other interesting possibilities were raised by the photos. Equally Voyager 2 Yields Surprises puzzling, Mr. Soderblom said, were long, intersecting slash‐like marks on the surface that appeared in the television images much like a mosaic. The marks suggested the possibility of a system of fault‐like fracturing on the surface of Europa.

But Mr. Soderblom said they looked extraordinarily shallow, resembling the mosaic‐like pattern when an egg shell is cracked. This appeared to militate against large‐scale fracturing.

The scientists said they would study the possibility that the surface of Europa is a thin ice‐crust overlying water and that the fracture slashes were evidence of breaks in the crust. Production of fresh ice or snow along Europa's cracks and glacier‐like flows might remove evidence of crater impacts.

Scientists have credited Voyager with a number of significant discoveries about Jupiter. It discovered a ring of particles around Jupiter and turbulent lighting and immense auroras in the planet's violent atmosphere, as well as turbulent volcanic еrupt)ons on Jupiter's moon Io. The Jet Propulsion Laboratory's scientists said they believe that, based on the data collected by Voyager 1, Jupiter and its moons do not closely resemble earth and other planets nearer to the sun, nor do they resemble each other. The flight of the Voyager 2, they said, had reinforced this conclusion.

Although Voyager 2, for the most part, is retracing the route of Voyager (which came within 172,000 miles of the planet), its instruments have been programmed to concentrate on areas and characteristics of the planet and its satellites that were missed by the earlier craft.

There was concern among some of the engineers working on the program today that the radiation, higher than expected, that has been encountered by the Voyager 2 while approaching Jupiter could endanger a radio transmission system that is already operating in a backup mode following trouble in the primary system.

Although the greater than expected radiation forced one of the 10 instпьments aboard the craft to be shut off briefly, scientists said the Voyager 2's various instruments returned an enormous volume of data to earth.

It photographed an area on the moon missed by Voyager 1 and used infrared and ultraviolet measuring instruments to collect other data about Ganymede.

The craft then turned its attention to Jupiter from a vantage point of 600,000 miles and began photographing the planet.

After passing within 127,000 miles of Europa, the Voyager 2 then shifted its attention back to Jupiter, making more photographs and measurements. Then it came within 347,076 miles of the moon Amaithea, taking more photographs and then making its final spproach to Jupiter. After passing the planet, the craft was scheduled to begin a reconnaisance of Io,