On the morning of May 14, 1973, a massive rocket rose with fiery thunder from its pad at Cape Canaveral, Florida, battering the earth with sound long after it vanished above the overcast. In minutes what looked like a winged silo was in orbit 270 miles out in space.

A few days later, after some trouble with one of the "wings"-actually panels to catch the sun's heat for electricity -had been repaired, a ferry ship from earth docked at the front of the big cylinder and its three passengers, two pilot- scientists and a doctor, went aboard as its crew for the next 26 days. They would be followed in turn by two more crews, each tentatively to stay for 56 days, according to how well the first made out during the shorter term.

The first arriving passengers found the interior of the ship befitting the needs of men who were going to be aboard a while. Once a hydrogen-filled fuel tank for a Saturn rocket, it had the space of a three-bedroom bungalow. It was fifty times larger than the first moonship.

To move about in the weightlessness of this unaccustomed spaciousness, the crewmen made use of handrails and foot holds, or they could strap a small rocket to their backs and "fly" like Buck Rogers, their comic strip counterpart.

In the aft compartment were a bathroom with shower and a kitchen with a central table where sitdown meals were served family style from a "pantry" stocked with 2,000 pounds of precooked food, including lobster Newburg and filet mignon. No longer did spacemen squeeze their food from a tube as if it were toothpaste. As they dined, whirling along at 17,500 miles an hour, they could look out a big porthole at the passing universe.

In the same section was also a bedroom. Since in the zero gravity of space there is no up or down, the beds were sleep ing bags secured to hooks on the wall. As he waited for sleep after he zippered himself in, the occupant could flip on a reading light and read, or he could throw another switch and listen to stereo music.

In the forward compartment, or "upstairs," was room amid the equipment to play catch or handball-or throw darts at a board.

This was Skylab, America's first manned space station. All that had gone before in the nation's space program, from the trailblazing hop of fifteen minutes by Alan Shepard to the first circlings of the earth and finally the flights to the moon, had been for pure science-to gather knowledge for knowledge's sake. Skylab's mission was to put some of this knowledge to practical use. This was the nation's second "giant step for mankind."

Now that man knew how to travel in space, could he live there? It was necessary to know this before he ventured on to farther points than the moon, which was really only next door. How would he do living in a state of weightlessness, weighing not an ounce?

Getting the answers to these questions was the first objec tive. With laboratory facilities and a doctor aboard to take blood samples and pulse rates, physical reactions could be studied as the flight progressed rather than after the return to earth.

But Skylab was also an observatory. There were nine tele scopes aboard, part of a $200 million package which included a variety of sensors to measure ultraviolet radiation. With no atmosphere to impede vision, it was hoped to learn many new things about the sun, especially concerning solar flares.

"We are excited about this project," said Dr. Riccardo Giacconi, of American Science and Engineering, at Cam bridge, Massachusetts. "We think solar astronomy will get a great boost from Skylab. . . . Moreover, the sun influences weather in mysterious ways. If we can determine the effects of its radiation and the activity of its flares on earthly atmo spheric currents and on our communications, we may be able in time, among other things, to predict long-range weather and interference with broadcasting."

In most of Skylab's 270 experiments, though, eyes would be looking homeward, back toward the garden in space. This would be done by means of sensors that operated in selected frequency bands in the visible, infrared and microwave ranges of the electromagnetic spectrum. It would also be done with a battery of six 70-millimeter cameras which could view the earth in six different bands in the visible and near-infrared portions of the spectrum.

With this formidable array of apparatus, capable of seeing things the human eye cannot, the Skylab men planned to search the earth for new mineral deposits, and to study such diverse subjects as soil types, distribution of the snow, kinds and conditions of crops and forests, and ocean temperatures. And they would be looking at the weather. There were thirteen programs on the agenda for atmospheric investiga tions, among them experiments designed to locate and com- bat air pollution and improve long-range forecasting. Hurricane Ava, centered five hundred miles southwest of Acapuico, Mexico, on June 6, gave the Skylab men a bonus opportunity early in the voyage to work on this part of the mission. While Air Force and NOAA planes flew over the hurricane far below, Skylab sailed along upstairs, shooting pictures of the storm in six different bands of the spectrum. With these spectroscopic cameras and yet another camera which took high-resolution pictures in black-and-white as well as color, with a three-dimensional effect, Skylab saw many things no one else did.

"The hurricane mission provided a unique opportunity to obtain data for many of the meteorological and oceanographic requirements of Skylab's first mission," commented Weather wise, the magazine of the American Meteorological Society. In addition to the formal programs, the crew could sit by the window like tourists and snap pictures impromptu with handheld cameras, tape-recording their remarks on what they saw.

When at last Skylab's systems were disconnected and her final crew returned to earth aboard the ferry docked at the front of the lab, on February 8, 1974, a staggering mass of information had been gathered. There were 182,000 astron omy pictures, 46,000 pictures of the earth, and fifty-four miles of tape containing billions of bits of information. There was enough data, the New York Times said, to keep one thousand PhDs and computers busy for years figuring out what had been learned and how it could be used.

By May, seventy-five billion bits about the sun alone al- ready had been accounted for. The sun had commanded center stage for Skylab's telescopes with an unusual display of solar flares. There was likewise a rich harvest of information in the category of meteorology, to the delight of weathermen.

Skylab was a kind of space age counterpart of HMS Chal lenger, which in the autumn of 1872 set out from Ports mouth, England, to probe the mysteries of the deep seas and their creatures, then largely unknown. Three and a half years later, after having crisscrossed all the world's major oceans in an argosy of nearly 69,000 miles -sounding, dredging, trawling, bottling specimens as she went- the ship came home with information which filled fifty volumes of 29,552 pages and took twenty-five years to compile.

Lodged in libraries throughout the world, the reports of HMS Challenger are still the starting point for studies of oceanography.

What Skylab's crews brought back from the atmospheric seas should go a long way to help the National Academy of Sciences meet its timetable for perfecting rainmaking, mod erating storms-and finding out if man is doing something to the climate which he shouldn't be doing.

The timetable called for 1980.