Smithsonian Astronomers Keep Hectic Pace

"We're dealing with a problem that man has never confronted before," said Fred L. Whipple, director of the Smithsonian Astrophysical Observatory, a few days ago. "That's what has made things difficult and why we sometimes seem to be working slowly."

The problem is to pin down in time and space an object travelling around the earth at about 18,000 miles per hour in an orbit constantly being changed by the earth's gravitational pull. Until last October, Whipple had expected that this object would be the American earth satellite planned to be launched as a project for the International Geophysical Year.

But since October 4, when Russia made her spectacular launching of Sputnik, he and his staff at the Smithsonian have had to concentrate their attention on the activities of Russia's two satellies and hope that the United States will eventually be able to add its offspring to the growing celestial brood.

The Smithsonian Astrophysical Observatory, whose operations are centered in a small office building at 79 Garden St. in Cambridge, was set up in June 1956 by the government to take charge of certain United States projects scheduled for the IGY, most important of which was the earth satellite program.

"Operation Moonwatch"


It is the coordinating center for all the amateur teams of satellite observers scattered across the country in "Operation Moonwatch," and it carries on all United States work in orbital computations of satellites. And Whipple says that "we sometimes seem to be working slowly;" this isn't the way it has appeared to his overworked staff, who have had little chance to stop and reflect on what they "seem" to be doing during the month-long Sputnik crisis.

Whipple, who besides being director of the Observatory is a professor of Astronomy at Harvard, is being assisted by J. Allen Hynek, visiting lecturer on Natural Sciences. Hynek is an associate director of the Observatory in charge of the satellite tracking progrm. The two of them, according to one of their staff-workers, "have practically lived at this office" since Sputnik made its appearance.

The Big Surprise

Since Russia's successful satellite launching was completely unheralded, and since the U.S. had not slated its attempt until next spring, the Smithsonian found itself partially unprepared on the night of October 4. Moonwatch teams had been organized, but with no advance warning their personnel was scattered and had to be hastily assembled for spotting duty. Programming schemes had not yet been fully worked out with which to prepare MIT's IBM machines to calculate the satellite's orbit from observational data. And a special telescopic camera, especially designed for the photographic tracking of a satellite, had just been dismantled for an operational check-up and would not be serviceable for another week.

Whipple, moreover, was in Washington for an IGY conference when the Russian satellite was launched. Hynek was at home when he first heard a news report of the event, but he quickly assembled a skeleton crew of Smithsonian staff-members and began to alert the hundred or more Moonwatch stations from the Garden St. office.

By the early hours of the next morning, several observation teams had reported sightings, but they were contradictory as to both time of sighting and direction of the object, and later that day Whipple conceded that they must have been "slow-moving meteors" taken as the satellite by enthusiastic spotters.

By that time, however, more believable reports of sightings had arrived from points such as Australia and Alaska, and these, coupled with data from radio contacts with the satellite established soon after its launching, were enough to permit preliminary calculations of its orbit.

Sputnik, it was found, would not be visible in the United States for about a week or ten days. Its orbit was such that it did not cross this country during the hours of morning or evening twilight, the only times at which it might be seen. The Moonwatch teams would have to wait until the orbit moved, or "precessed, enough for observation to be possible.

Megacycle Mix-up

This left the main burden of the early tracking operations up to the Naval Research Laboratories, located in Washington, which by prior arrangement was to attempt to get a "fix" on the satellite by radio. It had established special "Minitrack" stations across the country for this purpose. Unfortunately, however, these stations were geared to receive signals on 108 megacycles, the frequency the Russians had promised to use in their satellite's transmitter. They had to be completely overhauled in order to pick up the 20 and 40 megacycle signals which the Soviets decided to use instead.