US space agency Nasa has blocked Chinese citizens with valid US visas from its facilities – a move that effectively bars them from working at one of the most respected space research centres.Chinese nationals, who could only work at Nasa as contractors or students contributing to research, found out on 5 September that they had lost all access to Nasa’s systems and facilities, Bloomberg news reported, citing sources. Nasa then confirmed this, saying Chinese nationals would be restricted from using the agency’s “facilities, materials and networks to ensure the security of our work”. China’s accelerated space programme has alarmed the US and ramped up the race between the two biggest economies.Chinese astronauts are already excluded from the International Space Station (ISS) because Washington has barred Nasa from sharing its data with China. The latest restriction from Nasa only adds to the decline in scientific collaboration between the two sides because of national security concerns.As they compete to gain a technological edge, Beijing and Washington have also grown increasingly wary of each other. The suspicion has made it harder for some Chinese students, especially those studying science and tech, to get visas, or even enter the US, once they have secured a visa. There have also been several cases in the US recently of alleged espionage by Chinese nationals, and scientists in particular have come under the scanner. It’s unclear how much notice Nasa gave Chinese nationals who were working for the agency. Bloomberg News reported that they had suddenly found they were denied access to the a …
