DETECTIVES IN SPACE. Sensors mounted on satellites send a stream of invaluable scientific information back to earth; now the US is in danger of losing its commercial lead just as important new applications are emerging

BOLIVIAN drug authorities obtain maps of illegal cocaine-processing plants. US news networks release photos of secret Soviet military installations. UN aid officials are able to predict crop failures in Africa and divert food aid to stricken areas. Multinational mining companies find potential ore deposits under dense jungle and pay little for the exploration rights because the host government has no idea of the land's value. All of this is happening by using satellites hundreds of miles in space that produce detailed images of Earth. The issue of satellite remote sensing is gaining attention for these reasons:

Remote-sensing technology will play a major role in predicting natural disasters, avoiding famine, monitoring global pollution, and surveying inaccessible areas, such as the Chernobyl nuclear plant site, tropical rain forests, and foreign military installations.

The United States, industry experts say, is not transferring its primary remote-sensing system to the private sector fast enough, and is at serious risk of losing its technological and therefore its market lead.

The French launched a commercial satellite that surpasses US technology, and competitors in other countries - namely Canada, Japan, West Germany, and India - are setting launch dates for their own advanced remote-sensing satellites.

The unofficial policy of ``open skies'' - agreed upon by the US and other Western powers - compels commercial satellite owners to sell images to anyone who can afford them.

Some third-world countries object that satellite data, used by governments and multinational corporations in developed nations, leave them open to exploitation.

The Pentagon is concerned with the national-security implications of the next generation of remote-sensing technology.

There are two basic types of remote- sensing satellites: government (intelligence gathering) and civilian or commercial (weather, communication), although some foreign government systems are also commercial.

Commercial remote sensing began when the US government turned over its Landsat satellite system to the Earth Observation Satellite Company (EOSAT), a joint venture of Hughes Aircraft Company and the RCA Corporation. The French are competing with their own satellite, launched in February 1986, called SPOT. Both Landsat and SPOT are able to produce images of virtually any location on Earth and are directed by the ``open skies'' policy to sell those images to whoever can pay the bill. But some analysts contend that images of certain Western military sites will be ``unavailable,'' because of cloud cover or other ``technical'' reasons. Military vs. civilian uses

The biggest difference between military and commercial remote-sensing satellites is the degree of detail - or resolution - of the images. For example, if you bought a picture of a city block from Landsat, you would be able pick out any building or object bigger than 30 meters (about 100 feet). SPOT could pick out much smaller buildings, anything over 10 meters (about 30 feet). Military satellites, by contrast, could detail objects in the 3- to 4-inch range, such as a lost tennis ball stuck on a rooftop.

The military doesn't sell its satellite images. But for $100, EOSAT will sell you a black-and-white photo covering an area 110 miles edge to edge. SPOT will sell you a black and white print for $470; its better resolution covers a more detailed 37 miles edge to edge. You can get color prints from EOSAT for $300 and from SPOT for $515.

With each new satellite built, the sensors improve. ``I think that over the next decade you will see resolutions improve,'' says Peter Zimmerman, a physicist at the Carnegie Endowment for International Peace. ``To go to 5 or 2.5 meters requires no scientific breakthroughs. It could be done in the commercial sphere as soon as anybody found a market for it.''

But according to Charles P. Williams, president of EOSAT, there is no current market for the finer resolution. ``To go to a very fine resolution similar to what some government may have ... simply doesn't have commercial utility. You would be investing $500 or $600 million in an instrument that could not possibly be recovered.'' A finer-resolution satellite would generate considerably more data, significantly increasing processing and other costs. President Carter's secret directive

More than economic viability is limiting the resolution of commercial satellites. According to government sources, President Jimmy Carter signed a secret presidential directive in 1978 that set 10 meters as the limit for nonmilitary remote sensing. Pierre Bescond, president of SPOT's American subsidiary, says that the next two SPOT satellites now in development will remain at 10-meter resolution, but he maintains it has nothing to do with the secret directive. The next Landsat satellite, if Congress upholds its commitment to help fund it, advances to only 15-meter resolution.

Industry analysts, however, believe that markets for less than 10-meter resolution will develop, and if US companies are held to 10 meters, America will simply lose its lead in this technology.

The Pentagon is worried about the geopolitical effects of widely available high-resolution images. It is currently opposing, on national-security grounds, a consortium of media interests which wants to launch its own 5-meter-resolution satellite (Mediasat).

``There were terrible fears of geopolitical problems [with] the first TIROS weather satellite,'' says Mr. Zimmerman. He points out that each improvement in resolution has raised fears, but eventually the fears subside. ``This is a technology which is unregulatable and unrestrictable,'' he says.

But the US could lose its technological edge before the next series of satellites is even off the launch pad. The Reagan administration and Congress have made enormous cuts in the funding promised when EOSAT signed the contract to take over the Landsat program. Third-world objections

Since the market for remote sensing is in its infancy, EOSAT asked for transition funding to maintain the government's satellite system until revenues rise to cover expenses. This the US government originally agreed to provide until 1989.

``The threat itself is extremely serious,'' says EOSAT president Williams, ``If the government portion of the investment is not provided ... it would mean the end of new satellite construction for Landsat and a termination of the ... US technological thrust sometime in the early 1990s. It will allow the French and Japanese to take the lead in the '90s and beyond, and become the governing factors in the sales of satellite data.''

Many countries have raised objections in the United Nations to being ``sensed'' and then having the satellite data available on the open market.

There have been reports in the European press, for example, that satellite data were being used by mining companies headquartered in London to determine potential mineral deposits under inaccessible jungle areas. Several countries complained that the mining companies were able to buy the mineral rights from them at a very low price because these governments had no idea of the land's value.

``Now, that is always a possibility,'' says Mr. Williams, ``before they allow anyone to come in and mine or exploit any part of their natural resources they must do an adequate investigation ... into what they may or may not be giving away.''

At a 1982 UN conference on space, developing countries took the position that the ``dissemination of [remote-sensing] data to a third party should not be done without the prior consent of the sensed country.'' But their wording did not survive the UN's final draft, which offers only a set of general principles on the use of remote sensing.

``The UN simply will have little role to play except advisory,'' says Zimmerman, ``perhaps consensus building, perhaps smoothing of ruffled feathers.''

To help prevent exploitation, however, and to assist domestic planning and management activities, the UN and the US Agency for International Development now purchase and supply data to third-world countries for their own use.

All large-scale environmental changes, caused naturally or by human activity, leave what photo interpreters call a ``signature.''

Current satellite technology can detect signatures like soil erosion as the result of poor agricultural practices, toxic waste sites, locations of ocean dumping, clear-cutting in forests, massive development projects that destroy tropical rain forests, and the effects of acid rain. ``It won't make polluting more difficult,'' says Carnegie's Zimmerman, ``but it will make getting away with it more difficult.''

In the future, commercial remote sensors will not only be able to detect pollutants leaving a factory, but determine what the factory is producing. Opportunities for industrial espionage, one company spying on another, are also possible (cases involving aerial reconnaissance have already hit the courts).

Environmental programs at the UN, NASA, and NOAA, and dozens of individual programs at universities and research institutions around the world, are now using remote sensing for environmental purposes.

It's more than a convenience. Hundreds of thousands of lives have been saved as a result of the disaster-prediction capacity of remote sensors. For example, in May 1985, US weather forecasters predicted a hurricane in the Bay of Bengal, off the coast of Bangladesh.

Computer programs combined the data from meteorological stations in Bangladesh with ``real time'' (as it actually happened) information from the GOES and TIROS weather satellites, general hurricane behavior data, tidal predictions, and storm-surge records for the bay to predict when and where the storm would strike. This allowed for the evacuation of much of the coastal area. While more than 5,000 people lost their lives, a hurricane in 1970, before the early-warning system, killed 300,000. `I see open skies'

Perhaps even more important than predicting weather disasters is the ability to assess food production around the world. Using the TIROS and Landsat satellite, yield predictions can be made a month before harvest, enough time to adjust pricing and marketing policies, import and export plans, and economic programs for farmers. Longer-term drought and disaster preparedness plans can also be developed to select drought-resistant crops and optimum planting times.

Mining and oil exploration companies have joined agricultural interests as the biggest commercial users of remote sensing. Images can be specially processed, for example, to highlight areas with high concentrations of iron oxide and clay, which would indicate the presence of an ore deposit. Similar spatial processing can highlight areas with potential oil deposits.

``Commercial competition is what will govern remote sensing in the future,'' says the Carnegie Endowment's Zimmerman. Even without the US, remote sensing may become one of the most useful technologies ever developed.

Asked what he sees in the future as a result of remote sensing, Zimmerman pauses and then smiles: ``I see very little way for any nation to hide any threatening activities from anybody. ... I see open skies.''