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.
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.
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.
The reports that flowed into Smithsonian headquarters in the first few days therefore did not give exact enough satellite locations to make calculation of an orbit possible. Punched cards were fed into the type 704 computers at MIT, lights flashed and dials lit up, but the machines were not satisfied and haughtily "rejected" the information.
Operations at the Smithsonian office settled into the daily pattern of frenetic activity that they have followed ever since. The direct teletype line to the Naval Research Laboratory clattered out constant messages back and forth. A special section under Leon Campbell maintained contact with the various Moon-watch teams, receiving their reports, providing them with information, and answering their requests. There was continuous work in the examination and evaluation of reported sightings.
Perhaps one of the least conspicuous burdens was and is being carried on by the public information section, under the direction of John White. Ever since the evening of October 4, the Smithsonian and photographers, and the telephone wires have been jammed by requests for office has been filled with newspapermen information by the general public.
The Observatory was clearly understaffed for the work it had been called upon to do. But it was a government project, and in government offices authorizations for hiring additional personnel come slowly. A few days later, desperate and sleepless, White issued an appeal for volunteer aid from University students.
Once Sputnik began to be visible above the United States, the Moonwatch teams again became active, and now that radio contact with the first satellite has been lost, their daily reports provide the only information on the wanderings of Sputnik I and its fellow-travelling rocket.
Special Tracking Cameras
The Observatory is also advancing its work in setting up special tracking cameras for satellite observation. The one that has already been manufactured, though it was disassembled in early October, is now in operation at Pasadena, Calif. The others, it is hoped, will be ready by the beginning of next year. They will be located at Curacao, West Indies; Arequipa, Peru; Villa Dolores, Argentina; Maui, Hawaii; Tokyo, Japan; Woomera, Australia; Naini-tad, India; Shiraz, Iran; Cadiz, Spain, and Johannesburg, South Africa.
Whipple and Hynek express complete satisfaction with their observation system to date. Moonwatch teams were at an initial disadvantage in that they were located in positions from which the projected American satellite would be visible early in its life, but which were out of the range of visibility for the Russian satellite for about a week after its launching.
Their reports have now become much more accurate, and the programming techniques for the MIT computers have been perfected, so that satellite orbits are now easily calculable and the position of the first satellite, at least, can be exactly predicted for any one moment.
Whipple looks upon this past month mainly as an extremely valuable warmup period for his own organization. Experience in dealing with the Russian satellites have ironed out most of the wrinkles in the U.S. observation system that might have delayed Smithsonian operations had the American satellite been the first to take to the air.
The U.S. network of observation posts, Smithsonian officials also point out, is much more extensive than the Russian system. The Soviets have even expressed a desire to purchase some American photographic tracking equipment and have modeled their Moonwatch telescopes closely after the U.S. prototype. The implication is that once the U.S. gets a satellite up, it will be in a better position to gain scientific information from it than the Soviets are with theirs.
This is the only problem remaining--to get a U.S. satellite launched--and for that the Smithsonian, it is thankful, has no responsibility