Earth resource satellites - whose sensors help experts locate minerals, monitor crops, or track air pollution - are expected to become a profitable enterprise in the late 1980s. But the United States, which has pioneered in this field, may be watching from the sidelines.
France, the European Space Agency, and even the Soviet Union are planning to go after the remote-sensing business. The United States has no authorized program to succeed the present Landsat system. Landsat 4, now in orbit, is crippled by the loss of two of its four solar panels. A replacement satellite is available for launch next year. Planning beyond that, however, has been put on hold as the Reagan administration explores the prospects for selling both the US Earth resource and the weather satellite systems to private industry.
Even if a reluctant Congress were to go along with the sale and a buyer were found, it is unlikely that a private resource satellite could be in orbit much before 1990. Given an expected three-year life for the replacement Landsat, that would leave the US without a system in 1987 just when the foreign competition is expected to heat up.
This is why business people interested in remote sensing wish the administration would stop fiddling with the controversial satellite sale and get going with a new Landsat effort. The Land Remote Sensing Advisory Committee of the Department of Commerce, which represents such people, is strongly urging that an improved Landsat be built right away to avoid a data gap in 1987.
However, the administration is proceeding with arrangements for the sale. The Department of Commerce now is drafting requests for bids. These are to be issued in November. Replies are to be in by February. The secretary of commerce is to decide by May whether or not to strike a deal with one or more of the bidders. If he does agree to a sale, transfer of title would take place in October 1984.
So goes the administration's schedule. However, given strong sentiment in Congress against the weather satellite sale, it is doubtful that schedule will be maintained. Most observers expect Congress to insist that the government keep the weather satellite system. The Communications Satellite Corporation, which has already drafted a takeover proposal, estimates that the systems need to be sold together. It says Landsat, by itself, would be unprofitable for several years, and sale of weather data would be needed to compensate for this loss.
In the end, therefore, neither satellite system may be sold. The whole exercise would then amount to a costly delay in developing a new resource satellite.
''We should do whatever we can to get (an advanced Landsat) going. The cost could be transferred to industry later if the system is commercialized,'' says Michel T. Halbouty, chairman of the Commerce Department's advisory committee. Mr. Halbouty uses Landsat images to help companies find oil and mineral resources. Like many others in the remote-sensing business, he is more interested in a continuing supply of data than in who owns the Landsat system itself.
Meanwhile, Landsat controllers at the NASA Goddard Space Flight Center are trying to make the most of their ailing satellite. Landsat 4 was in trouble even before it lost half its solar panel power supply. Launched on June 16, 1982, it carries two sets of sensors. One, called the Multi-Spectral Scanner (MSS), has become standard Landsat equipment. About a dozen nations regularly use its data. The second set of scanners, called the Thematic Mapper, is an advanced experimental unit that produces sharper images. The MSS is busily supplying its users. But the Thematic Mapper has been out of service since March after failure of the radio which transmits its data to ground stations.
Now Goddard controllers hope to get the Thematic Mapper back in business. The Tracking and Data Relay Satellite (TDRS-1), which the shuttle astronauts are using this week, can also serve Landsat 4. TDRS-1 now is parked in orbit 22,300 miles high at 67 degrees west longitude. There it can relay Thematic Mapper data which it receives via a Landsat radio link that is unsuitable for direct transmission to the ground.
Indeed, this is the primary way Thematic Mapper data were supposed to be sent. But TDRS-1 took 12 weeks to reach its station after a malfunctioning booster rocket put it in the wrong orbit last April. The data relay satellite didn't begin operational tests until Aug. 7.
William Webb, deputy project manager for Landsat 4, says the tests show the relay works. It is a high fidelity system. Landsat designers had expected to get one error in every hundred thousand data bits. They actually are getting only one bad bit in ten million.
The tests have been suspended while TDRS-1 services the space shuttle Challenger. However, Webb says he expects the Thematic Mapper will soon be back in business.
He is less certain about the life of Landsat 4 as a whole. The two solar panels supply enough power to collect the data needed. But one or both of them could go at any time. The most that Webb can say is that Landsat 4 should be working for some time - perhaps into next year. But it is impossible now to predict how long that may be. Hence the pressure to launch the Landsat replacement - the last US resource satellite - early next year.
The administration should take the advice of the Commerce Department's committee and keep the US in the resource satellite business. If it must pursue the satellite sale, it could at least provide continuity for the Landsat program while it sorts out its controversal policy with Congress.