Japanese scientists have managed to open only one of two massive antennas on the country?s biggest-ever satellite after its launch just over a week ago, a spokeswoman for Japan?s space agency said yesterday. Scientists abandoned the attempt to unfold the other 17-metre antenna on Monday when it took longer than planned, but they expect to succeed when they make a second attempt later in the day, she said.

The successful launch of the Kiku experimental communications satellite on a domestically developed H2-A rocket from southern Japan earlier this month was seen as a boost for Japan?s plans to enter the commercial satellite business.

Those plans were dealt a devastating blow in 2003 when an H2-A carrying two spy satellites veered off course and had to be destroyed. Japan last year announced ambitious targets for its space programme, including manned space flight ? a feat already achieved by Asian rival China. Kiku is intended to improve mobile phone-based communications and help develop technologies for a satellite-based multimedia broadcasting system for mobile devices, the agency said on its Web site.