The Way to Go in Space; The Future of Space Exploration; Scientific American Presents; by Beardsley; 18 Page(s)

The year 1996 marked a milestone in the history of space transportation. According to a study led by the accounting firm KPMG Peat Marwick, that was when worldwide commercial revenues in space for the first time surpassed governments' spending on space, totaling some $77 billion. Growth continues. Some 150 commercial, civil and military payloads were lofted into orbit in 1997, including 75 commercial payloads, a threefold increase over the number the year before. And the number of payloads reaching orbit in 1998 was set to come close to the 1997 total, according to analyst Jonathan McDowell of Harvard University. Market surveys indicate that commercial launches will multiply for the next several years at least: one estimate holds that 1,200 telecommunications satellites will be completed between 1998 and 2007. In short, a space gold rush is now under way that will leave last century's episode in California in the dust.

The need for better launch systems is already immediate, driven by private-and public-sector demand. Most commercial payloads are destined either for the now crowded geostationary orbit, where satellites jostle for elbow room 36,000 kilometers (22,300 miles) above the equator, or for low-Earth orbit, just a few hundred kilometers up. Low-Earth orbit is rapidly becoming a space enterprise zone, because satellites that close can transmit signals to desktop or even handheld receivers.