Recently unveiled plans by Dutch and Chinese universities to fly a scientific mission in which two small satellites will fly in formation has aroused some concern that the experiment could lead to improved Chinese military space capabilities.

The environmental-monitoring mission, slated to launch in 2011, involves one satellite built by the Delft University of the Netherlands and one built by the University of Tsinghua in China. “Both satellites will fly either in formation with [lateral] separation of a few hundred kilometers or in a train configuration. In both cases, formation-keeping requirements will be low,” Eberhard Gill, one of two Delft professors involved with the project, said via e-mail in response to questions from Space News.

According to a press release issued Jan. 7 by the Delft University, the satellites will measure particles in the atmosphere, such as soot, as well as snow and ice levels on the ground.

The data will be used to better understand “the influence of air pollution” on climate change, according to the release.

According to the press release, flying multiple satellites in formation offers substantial scientific information-gathering benefits. “By sending satellites to orbit the Earth in formation many more and improved observations can be made than if just one satellite is used. Two satellites in formation together generate almost three times as much data as one satellite,”

the Delft press release said.

But formation flying has military as well as scientific applications, experts said.

“It can be a powerful technique for information gathering. The trick is precision: the satellites need to know where each other are – the higher the accuracy, the more the information benefit. Turns out

it’s hard,” retired U.S. Air Force Maj.

Gen. James Armor, a consultant who was until recently director of the Pentagon’s National Security Space Office, said via e-mail


A U.S. analyst who keeps close tabs on Chinese space activities, Dean Cheng of

the Center for Naval Analyses

in Alexandria, Va.,

said the Sino-Dutch experiment has relevance to computer-linked satellite clusters that can adapt on orbit to the mission at hand. Such clusters can, for example, form a single observation aperture that can be adjusted on orbit.

Armor cautioned against getting overly concerned

about the project, saying the United States and other nations need to be thinking about how to work with the Chinese.

Joan Johnson-Freese, chairman of the Naval War College’s department of national security decision making, said any U.S. concerns about the Dutch-Chinese say more about the United States than they do

about any threat posed by China. “What is space science to one group … is national security to the United States,” she

said via e-mail.

Johnson-Freese explained that globalization of the space industrial base removes technology and operations from U.S. control, “and we have yet, I think, to accept that.”

Gill said he understood concerns about the mission, but said China possessed the technical ability to perform formation flying without help from the Netherlands.

“Having worked in the field of formation flying for the past

few years, I would expect that formation flying even with high accuracy demands can be realized solely by China without international cooperation,” he said in his e-mail. “The proposed mission concept is open in the sense that other nations can join the train, similar to existing concepts such as the international A-train.”

The A-Train is an international environmental monitoring effort consisting of five satellites flying in the same 705-kilometer orbit, one behind another. It is led by

NASA’s Aqua spacecraft and includes

the U.S.-Canadian Cloudsat, the U.S.-French Calipso, the French Parasol and NASA

Aura satellites.

Gill said the Delft University would take into account concerns about technology sharing and the possible operational utility of some of the formation flying “in the upcoming design of the mission.”