Thank you Liss. At the moment we only know that SJ-12 was built by the Shanghai Academy (SAST), i.e. the same manufacturer as for SJ-7, whereas SY-1 was built by Harbin Insitute of Technology. Both SJ-7 and SY-1 seems to have been used for observation and tracking of the Asat test in January 2007. There are rumors at 9ifly that SJ-12 could have IR-sensors on board.