Kompsat - 3A - Earth observation satellite and part of the Korean Multipurpose Satellite Program, created by KARI Korea Aerospace Research Institute). Thanks to them is opportunity to observe satellites carrying optical, radar payloads. This satellite carries an optical imaging system to wavelengths in the visible and infrared range. Kompsat -2 and Kompsat-3 have similar payloads.
The beginning of Kompsat mission date from 1999. The first Kompsat had 470 kg and 6.6 meters. The next satellite - Kompsat 2 had 800 kg and it used latest fashion satellite bus. Kompsat-2 launched in July 2006. The Kompsat-3 was launched in 2012 and it had similar architecture as Kompsat-2. Payload was better and reached a resolution of one meter for panchromatic imagery.
Kompsat-3A is the sister of Kompsat-3. It uses the same satellite bus and payload. What is new is added infrared capability. Kompsat-3A was launched on 25 March at 22:08.