The Environment and disaster monitoring satellite A and B were launched successfully on September 6, 2008. HJ-1-A
carried CCD and HIS (Hyperspectral Imager) on it, and HJ-1-B carried CCD and IRS. The CCD sensor has 4 bands, which
are the near-infrared, red, blue, green. And the CCD special resolution is 30m, the swath width is 360km (per set).HJ-1-A
and HJ-1-B have the same orbit, and the revisit time is two days while working together.