TOKYO — Japan’s Ministry of Trade and Industry (METI) is aiming to launch a series of relatively small but high-resolution optical and radar Earth observation satellites starting 2011 aboard a newly designed Japanese solid-fuel rocket. Data from the satellites would be used by the Japanese government and military, and also marketed commercially.

According to Norihiko Saeki, deputy director of METI’s Space Industry Office, Tokyo-based NEC Corp. is building the first 450-kilogram test satellite, which will be able to resolve ground objects as small as a half-meter across. The satellite would be launched aboard the three-stage Advanced Solid Rocket, being developed by the Japan Aerospace Exploration Agency and IHI Aerospace Ltd. of Tokyo. Work on the optical satellite and rocket is already under way.

Plans call for work to begin next year on a similar-sized X-band radar satellite with better than 1-meter imaging resolution, according to Saeki.

METI is finalizing a contract with the Tokyo-based geospatial information provider Pasco Corp. to disseminate the data globally from these and future satellites, Saeki wrote in a July 17 e-mail.

Saeki said the effort is part of METI’s Space on Demand program formulated in late 2007 to promote lower-cost satellites with shorter development times and improved functionality compared to Japan’s legacy Earth observing spacecraft. Also envisioned under the Space on Demand concept are quick-reaction launch vehicles that could launch from aircraft or submarines and satellites that are reprogrammable in orbit.

Unlike the U.S. Defense Department’s Operationally Responsive Space Program, which Saeki characterized as driven primarily by military requirements, Space on Demand’s ultimate aim is to boost the efficiency and capability of Japan‘s space industry.

“[This] satellite-based monitoring system is regarded as a complementary system for aerial or ground systems. … In order to shorten the revisit time, we have chosen the small satellite approach and are seeking cost benefits,” Saeki said. He said the Operationally Responsive Space and Space on Demand programs have different objectives, but acknowledged their similarities.

METI is emphasizing the commercial partnership side of the program, which has Pasco responsible for selling and marketing images, he said.

Tetsuo Fukunaga, deputy director of Pasco’s Satellite Business Division, said in a July 17 interview that the company expects to finalize in the coming weeks a deal where Pasco will be responsible for the system’s ground segment and will operate two ground stations: an existing Pasco-owned facility in Okinawa and a new station in Hokkaido, northern Japan, which will be ready in 2010.

Pasco already has exclusive Japanese reception and distribution rights for data from Germany‘s TerraSAR-X radar satellite, he said.

Both the optical and radar demonstration satellites have been authorized for development in the Basic Plan for Space Policy, Japan‘s latest 10-year space policy, under a program dubbed Advanced Satellite with New System Architecture for Observation, or Asnaro. The project is run by METI’s space arm, the Tokyo-based Institute for Unmanned Space Experiment Free Flyer.

In a July 22 e-mail Koichi Ijichi, manager of the METI space division, said the optical satellite will use a newly developed small-satellite platform for Earth observation and scientific missions. The design is the result of a joint study by the Japan Aerospace Exploration Agency’s Institute for Space and Astronautical Science and NEC.

According to Saeki, the Asnaro project — the initial optical satellite was approved before the Basic Plan came out — has received about $20 million to date. The satellite is expected to cost about $30 million in total, he said.

According to the Basic Plan, the radar satellite should be launched in 2014. Saeki said METI has yet to award a prime contract for the craft.

NEC does not have any detailed information on the future plans of METI relative to the Asnaro program, YoshitoNarimatsu, senior technology executive at NEC’s Space Systems Division, said in a July 22 e-mail response to questions.

The Basic Plan calls for development of a two- to four-satellite pan-Asian observation system featuring a mix of optical and radar satellites to be launched starting in 2015.

Saeki said METI is still working out the balance of optical and radar satellites in the eventual constellation. “It depends upon evaluation of performance of the optical and radar satellites. We are studying the best mix of the satellites right now,” he said.

A graduate of the Columbia Graduate School of Journalism, where he won the Horgan Prize for Excellence in Science Writing, Paul Kallender-Umezu is co-author of “In Defense of Japan: From the Market to the Military in Space Policy” (Stanford University...