- Sounding rockets are primarily used for probing the upper atmosphere and for space research. - ISRO's Rohini series includes rockets like RH-200, RH-300, and RH-560, named after their diameter in millimeters. - These rockets are launched from various locations in India, including TERLS (Thumba Equatorial Rocket Launching Station) and SDSC SHAR (Satish Dhawan Space Centre, Sriharikota).