ISRO has been launching indigenously made sounding rockets since 1965, and in 1975, all sounding rocket activities were consolidated under the Rohini Sounding Rocket (RSR) Programme ISRO, India’s premier space research organisation, has invited proposals from the national and international scientific community for innovative payloads for scientific experiments to study the middle and upper atmospheric regions. The ‘Announcement of Opportunity’ (AO) is for scientific payloads to be carried on the Indian Space Research Organisation’s sounding rockets. The sounding rocket carries instruments and has been designed to take measurements and perform scientific experiments during its sub-orbital flight. They are generally one or two-stage solid propellant rockets and have been used in the context of taking measurements. Some of the research avenues that can be explored with sounding rockets are aerosol experiments, middle atmospheric winds, temperature and composition, meteor smoke particle detection, ionospheric electron density, irregularities and ion composition, plasma, solar and astrophysics, and so on. Along the same lines, ISRO has invited proposals with innovative ideas in the realms of atmospheric and space sciences, astronomy and astrophysics from scientists from member nations of the United Nations. Also, the payload of a sounding rocket consists of nose cone, payload cylinder, ejection and/or separation mechanism, mounting decks, avionics systems and scientific instruments. The launch station has tracking radars with real time data processing and data uplink system, says ISRO. Those interested can send the proposals to Director, Space Science Programme Office, ISRO HQ, Antariksh Bhavan, New BEL Road, Bangalore 560231, Email: srao@ISRO.gov.in by 31 December 2019. For more details on the Announcement of Opportunity’ do check the brochure available on the official ISRO website.