Why in News:

• Indian Space Research Organisation (ISRO) hopes to achieve the 200th successful launch of the Rohini RH-200 sounding rocket in a row.

About

• The 3.5-metre-tall RH-200, a trusted member of the Rohini sounding rocket family used by the ISRO for atmospheric studies.
• RH-200 is a two-stage rocket capable of climbing to a height of 70 km bearing scientific payloads.
• The first and second stages of RH-200 are powered by solid motors. The ‘200’ in the name denotes the diameter of the rocket in mm.
• For years, the RH-200 rocket had used a polyvinyl chloride (PVC)-based propellant. The first RH-200 to use a new propellant based on hydroxyl-terminated Polybutadiene (HTPB) was successfully flown in 2020.

Importance of Sounding rockets

• Sounding rockets have since been used for a variety of experiments, including those on phenomena related to eclipses
• The first sounding rocket to be launched from Thumba was the American Nike-Apache – on November 21, 1963. After that, two-stage rockets imported from Russia (M-100) and France (Centaure) were flown.
• The ISRO launched its own version – Rohini RH-75 – in 1967.

How does RH-200 still help us

• RH-200, during its flight, encounters severe environment peaks and is an ideal platform to assess new technologies, testing their airworthiness by exposing them to hostile environments.

Reference:

1. https://www.thehindu.com/news/national/kerala/isro-eyeing-200th-successful-launch-of-rh-200-sounding-rocket-in-a-row/article65931221.ece
2. https://www.isro.gov.in/launchers/100th-consecutively-successful-launch-of-sounding-rocket-rh-200-terls