India’s Space Odyssey: 50 Years Since Aryabhata’s Historic Launch
Today, April 19, 2025, marks the 50th anniversary of Aryabhata, India’s first indigenously built satellite, which was launched from the Soviet cosmodrome in 1975. This historic event launched India’s satellite odyssey, and since then, the Indian Space Research Organisation (Isro) has built 131 satellites, with 51 currently in orbit. According to a report by The Indian Express, Aryabhata’s successful launch was a significant milestone in India’s space exploration journey.
The Aryabhata satellite was named after the ancient Indian astronomer Aryabhata and was launched from Russian soil on April 19, 1975. Interestingly, it took just 30 minutes after the launch for the first signals to be relayed back to the Indian ground station located in Andhra Pradesh’s Sriharikota, about 5,000 km away from the Soviet military rocket launch complex. As The Indian Express reported, the Rohini Sounding Rocket Experiment and subsequent experiments since 1963 from the Thumba Equatorial Rocket Launching Station in Thiruvananthapuram, established by Vikram Sarabhai, had tasted success multiple times.
Collaboration with the USSR
On May 10, 1972, India inked an agreement with the Academy of Sciences, the Union of Soviet Socialist Republics (USSR), to undertake joint research with other countries. As per The Indian Express, it was agreed upon that within two to three years, an Indian-made satellite would be launched from the Soviet cosmodrome. However, due to India’s nuclear test at Pokhran in May 1974, the United States imposed sanctions on the country, obstructing any transfer of knowledge or technology that may prove handy towards building Aryabhata.
Pramod Kale, former director of the Vikram Sarabhai Space Centre, suggested that the name Indo-Soviet Satellite Programme be changed to the Indian Scientific Satellite Programme, so it would possibly draw fewer international eyeballs on the nation’s space ambitions. The Indian Express reported that the Isro Satellite Systems Project was established at Peenya village, near Bangalore, which offered close proximity to institutions like the Hindustan Aeronautics Limited (HAL), along with a conducive environment supported by the presence of industries.
Designing and Building Aryabhata
U R Rao, credited with developing India’s satellite technology, led a 200-member team of engineers and scientists who built Aryabhata at Peenya. As reported by The Indian Express, the spacecraft’s quasi-spherical shape was unique, and it included three scientific experiments: for X-ray astronomy, for observing solar neutrons and gamma rays, and one for studying the upper atmosphere. The satellite model was even taken up in a helicopter over Sriharikota during January 1975, and the two-way communication link between the satellite and the ground telemetry station at Sriharikota was checked under simulated power levels of the transmitters.
Lasting Impact
Today, half a century later, satellite-based communication is well-established and widely used, but its roots in India can easily be traced back to Aryabhata and Isro. As The Indian Express reported, the first voice transmission of a recorded speech was transmitted from Sriharikota to Bangalore via Aryabhata. Due to its high quality, another experiment involving electrocardiogram (ECG) signals was similarly transmitted, demonstrating the opportunities and unlimited possibilities that satellite communication could offer in the future.
In an interview with The Indian Express, Kale mentioned that the presence of the sea nearby and the recurrent salt water splashes prevented the setting up of the quintessential instrumentation or clean room facilities for space activities in Kerala’s capital. He also mentioned that it was decided to shift the activities to Bangalore, which offered a conducive environment supported by the presence of industries. The Indian Express reported that S Radhakrishnan, 72, who worked at a factory in Peenya in the 1970s, recalled catching a glimpse of the then prime minister Indira Gandhi, who had made multiple trips to Bangalore, inspecting Aryabhata at crucial stages ahead of its launch.
The Aryabhata satellite was a demonstration of India’s indigenous abilities to undertake the structural designing of a space-worthy satellite, fabricate and test it, develop thermal and power control systems, as well as an entire ground station along with data processing systems. As per The Indian Express, with over 12,000 electronic components, 20,000 solar cells, and more than 25,000 interconnections within the satellite, Aryabhata was a testament to India’s growing capabilities in space exploration.
