Astro C (renamed Ginga after launch) was an X-ray astronomy satellite. This spacecraft housed the following three X-ray astronomy experiments:

- Large Area Proportional Counters (LAC)
- All Sky X-Ray Monitor (ASM)
- Gamma-Ray Burst Detector (GRBD)

The spacecraft provides a three-axis stabilized platform. The primary mission objective was the study of the time variability of X-rays from active galaxies such as Seyfert galaxies, BL Lac objects, and quasars. Accurate timing analysis of galactic X-ray sources was also planned.