Private businesses scan horizons in space travel. A Houston team may be first with a manned station

The advent of the shuttle has launched an era of space entrepreneurs with their feet on the ground and eyes on the potential profit of this new commercial frontier.

More than 30 businesses nationwide have announced their intentions to provide a slew of services to and from space in the near future.

The first manned space station, for example, may be built and funded by a group of Houston space entrepreneurs rather than by the National Aeronautics and Space Administration, despite the Reagan administration's encouragement of NASA plans to have a station in orbit by 1991.

Maxime A. Faget, former director of the Johnson Space Center and current president of Space Industries Inc., will decide soon, along with his associates and investors, whether or not a privately funded space station designed for commercial use will generate a profit for investors. If all systems are ''go,'' the first manned space station will be a private business venture.

Mr. Faget is typical of those, many of them former NASA officials, who see considerable potential in the commercialization of space. Most of their companies are in a start-up mode and their ideas, for the most part, are still on the drawing boards. And many are still pursuing venture capital. Sending satellites into geosynchronous orbit (hovering 22,300 miles above the same spot at the equator) or providing low-cost launch services takes millions of dollars.

Two years ago three young Harvard students considered how the government might encourage more private investment in space operations. They discovered a lack of entrepreneurs willing to take risks. So upon graduation, David W. Thompson, Bruce W. Ferguson, and Scott L. Webster set up Orbital Systems Corporation. In April the three men signed an agreement with NASA to develop and market a privately funded propulsion system for launching satellites from the space shuttle into geosynchronous orbit. The company will use Martin Marietta Corporation, builder of the Titan rocket, as prime contractor and United Technologies Corporation as supplier of the solid-fuel rocket.

The three men have raised $2.75 million in equity using research-and-development limited partnerships, a way of raising funds that offers investors a special tax break. They have also raised capital through a consortium of major investment banks in New York. The project will require about

The first pioneer of private space enterprise, Houston real estate developer David Hannah, used these R&D limited partnerships very successfully. He was able to raise the capital for Space Services Inc. of America, a private launching service for satellites. SSI had 12 backers for its first $1.2 million rocket, Percheron, which blew up in a prelaunch test in August of 1981. By the time of SSI's second, successful launching - Conestoga I last September - Mr. Hannah had raised $6 million from 57 people who invested from $5,000 to $100,000. He himself put in $1.5 million. He also offered investors a $1-a-share stock option which most have accepted, according to Hannah. Future rockets will probably use programs structured like the oil and gas industry's drilling programs, another type of investment program with tax advantages, according to SSI's legal counsel , Art Dula.

Mr. Dula, incidentally, is the first private practitioner of space law and is internationally recognized for his efforts to protect the interests of free enterprise in space.

The potential market for space technology is large, according to studies. In addition to launch services, SSI's market studies indicate a $2 billion (largely governmental) market in remote sensing or continuous photographing of Earth. Sensing is used now in monitoring agricultural yields, detecting timber infestations, and scouting likely geological formations for oil and mineral exploration. A $100 million market exists for ''positioning'' satellites that allow geophysical vessels engaged in seismic work to pinpoint positions, Hannah said. And a market exists for data and voice communications from multiple satellites in communication with one another at low-Earth orbit rather than larger, more expensive satellites in geosynchronous orbit.

Orbital Systems cites market studies that project a 20 percent annual growth rate in the number of new satellites through the early 1990s as well as substantial replacement rates for present satellites. The commercial and world space transportation market is estimated at between $10 billion and $15 billion from 1983 to 1995, according to Dr. Klaus Heiss, president of Space Transportation Company, which is working with NASA on a proposal to fund a fifth orbiter privately.

The investors behind these ventures tend to be people who view space as a good long-term investment, akin to the early advocates of the airline industry. In 40 years, space transportation will be routine and inexpensive via common carriers from Earth's surface to low-Earth orbit, according to Mr. Dula. Most commerce in the inner solar system will be privately owned and will operate for profit, principally in energy, communications and information, and materials manufactured in space and returned to Earth. Privately funded ''world corporations'' that do not rely on the jurisdiction of any nation-state will begin to predominate in space. Governments will be involved in exploring the outer solar system, but resource mapping and exploration will be done by privately owned space corporations.

''The great fortunes of the next century will be made in the asteroid belt, and the most important aspects of space development will be largely independent of Earth for raw materials,'' Mr. Dula said.