Last week’s successful launch by India of two satellites was clear evidence international competition to explore the empty reaches of space is beginning to heat up.

The swelling number of countries both willing and able to explore outer space also suggests the United States’ past domination is no guarantee of future mastery.

India – possibly the most underrated spacefaring nation of all – best epitomizes this new international space race.

Most of the recent publicity about India’s space effort has centered on its plan to launch an unmanned probe to the moon by 2007.

If successful, Chandrayan-1 would make India a member of a very select club – which includes the United States, Russia, and Japan – as the only nations able to send a spacecraft to another planet. The European Space Agency also has flown planetary missions, but only as a consortium of 16 nations.

What hasn’t been noted much is the long-term stability and steady growth of India’s program. Since its inception in 1969, the Indian Space Research Organization has developed two different launch rockets for placing satellites in orbit, the Polar Satellite Launch Vehicle and the Geostationary Satellite Launch Vehicle.

PSLV gives ISRO the ability to put more than a ton into low polar orbit, while GSLV can put almost 2.5 tons into geosynchronous orbit, as well as send unmanned spacecraft to the moon and beyond.

The May 5 PSLV launch of Cartosat-1, a remote sensing satellite able to photograph objects as small as 8 feet across, and Hamsat, an amateur ham radio communications satellite, also inaugurated ISRO’s second launchpad, located at its Satish Dhawan Space Center on the country’s eastern coast, 50 miles north of Chennai.

Designed to accommodate India’s entire rocket fleet, as well as any future upgrades, the space center gives India a launch flexibility superior to most other space programs.

India, however, is not the only country whose space program is blossoming. Consider China’s aggressive space program. On Oct. 15, 2003, it completed its first manned mission, putting astronaut Yang Liwei into space for 14 orbits.

This fall China plans to launch its second human spaceflight, using its Shenzhou spacecraft to put two astronauts in space for at least five days.

In addition, Chinese officials have said they plan to send unmanned orbiters and landers to the moon within a decade, followed by an unmanned sample return mission by 2020.

Faced with this nearby competition, Japan – for decades Asia’s leader in space exploration – has been forced to rethink its own program.

On Oct. 1, 2003, just two weeks before the Chinese manned mission, the Japanese government reorganized its space program, merging three separate departments into the Japan Aerospace Exploration Agency.

Since then JAXA has proposed that rather than rely on the United States or Russia to put its astronauts into space, the country should establish its own long-term space exploration plan.

That includes putting robots on the moon by 2010, followed by a Japanese-built human reusable shuttle program designed to establish a manned lunar base by 2025.

Asia is not the only place where new space exploration plans are being fostered. The European Space Agency, for example, has an increasingly proficient unmanned planetary program.

Not only has ESA had success with its Mars Express and Smart-1 probes, presently in orbit around Mars and the moon, respectively, ESA is to launch its first probe to Venus on Oct. 26.

Just as significant, in December 2003 – even before President George W. Bush announced his space initiative to return to the moon – ESA released its own long-term plans for the exploration of the solar system, including a Mars sample return mission in the next decade, a manned mission to the moon by 2024, and a human expedition to Mars by 2033.

Russia also is in the mix, still aggressively pursuing efforts to colonize space. Russia dominates the world launch industry because of its ability to reliably and cheaply launch both humans and satellites into orbit.

If all goes as planned, by 2010 Russia will have completed its half of the International Space Station, replaced its venerable Soyuz manned spacecraft with a fleet of its reusable Clipper spacecraft, and begun work on sending humans beyond Earth orbit by 2015-2020.

“The Clipper spacecraft can fly to the moon and farther,” said Anatoly Perminov, director of the Russian Space Agency, according to a report by the RIA-Novosti news agency.

Some of these plans are nothing more than bureaucratic lobbying and will never happen. For example, Japan’s government has not yet agreed to finance its space agency’s proposals.

Nonetheless, the burgeoning efforts of these countries give us our first inkling of who the players will be in the grand interplanetary effort to colonize the solar system over the next few centuries.

We are at the dawn of a new colonial age. The growing space competition between nations is in many ways very reminiscent of the 19th century competition between the European powers to colonize Africa and the South Pacific.

In the 1800s, Germany, France, Belgium, the Netherlands, and the United Kingdom aggressively competed to carve up the undeveloped world. The result was foreign-run colonies controlling most of the Third World, for both good and ill, for almost a century.

Today, a new list of nations – India, China, Japan, Russia, Europe and the United States — are throwing their resources at space exploration in much the same way.

Their goal, unstated but indisputable, is similar to the colonial powers of the 19th century: to obtain future domination over unclaimed territories in space.

This quest will, like the previous colonial efforts, be a long, complex and difficult historical process.

Just as the colonial movement dominated much of 19th century politics and history, the growing desire by nations today to settle and control the solar system is also likely to dominate human history for centuries to come.

The significant difference, however, is there are no aborigine peoples in space. The colonization of the solar system offers the hope of oppressing no one while bringing benefits to everyone who does it.

Robert Zimmerman is an independent space historian and the author of “The Chronological Encyclopedia of Discoveries in Space.” His most recent book, “Leaving Earth: Space Stations, Rival Superpowers, and the Quest for Interplanetary Travel,” was awarded the Eugene M. Emme Award by the American Astronautical Society for the best popular space history in 2003.