Amy Svitak Paris, Brussels and Berlin

Chile has one. So do Turkey and the United Arab Emirates (UAE). By the end of April Vietnam could, too.

Over the next decade more than 280 Earth-observation-satellite systems are expected to be launched into orbit, with roughly 30% lofted for developing space programs in Asia, Latin America, Africa and the Middle East—regions where technology transfer is key to fostering fledgling industries, according to Paris-based Euroconsult.

Earth-observation satellites and the increasingly sharp imagery they produce are the fastest-growing segment of a commercial remote-sensing industry currently dominated by Western suppliers, a market that is projected to generate nearly $4 billion in annual revenue by 2021. But as emerging space economies gain technological know-how—much of it via satellite contracts with European and Asian manufacturers—established companies in the U.S. and Europe will navigate an increasingly dynamic competitive landscape.

Many of these new entrants are seeking Earth-observation satellites of their own to meet defense and civil needs—everything from military surveillance to crop monitoring and urban planning. Other countries simply buy imagery on the commercial market, which today is led by sub-meter-resolution heavyweights DigitalGlobe of Longmont, Colo., EADS-Astrium Services and Telespazio of Rome. At least one has opted to finance an entire constellation in exchange for access to its data, as Beijing-based Twenty First Century Aerospace Technology Co. did in 2011 under an agreement with British small-satellite manufacturer Surrey Satellite Technology Ltd. (SSTL), a subsidiary of Astrium.

But an increasing number are seeking technology and know-how to bolster burgeoning domestic space programs, including some with the potential to sell imagery and data on the commercial market.

For example, Turkey is investing heavily in developing its domestic space program, one that already boasts several telecommunications satellites and two Earth-observation spacecraft, with plans to produce more.