NASA ban on Chinese scientists improper

US space agency NASA\'s decision to exclude Chinese scientists from an upcoming science conference was \"improper,\" a Chinese official said on Saturday. \"It\'s improper to disqualify Chinese researchers from international exchange due to their nationality,\" said an unidentified spokesperson with the China Association for Science and Technology. Six Chinese participants were refused attendance at the Kepler conference, scheduled to take place at NASA\'s Ames Research Center in California in November. The decision by NASA has sparked discontent from both Chinese scientists and some prominent US astronomers who vowed to boycott the conference. The exploration of the universe is a common undertaking endeavored by all human beings, and international exchange and cooperation are vital to advancing scientific progress, said the spokesperson. \"I hope the issue can be resolved in a good way, so that the openness and cooperation of scientific research can be promoted,\" the spokesperson said. \"We\'d like to increase exchanges and share experience in developing space technology with other nations.\" NASA administrator Charles Bolden said Thursday that he had directed the space agency to reconsider applications of Chinese researchers. However, the US government shutdown since Oct. 1 over Republican opposition to President Barack Obama\'s health care reform has probably hampered efforts to resolve the spat, according to organizers of the conference.