When India dives into the deep sea: Understanding Samudrayaan
India is making significant strides in deep-sea exploration with its ambitious mission, Samudrayaan. Led by the National Institute of Ocean Technology (NIOT), Chennai, under the ministry of earth sciences, government of India, this groundbreaking initiative aims to send a crewed submersible to a depth of 6,000 meters (20,000 feet) in the Indian Ocean. Samudrayaan is a key component of India’s Deep Ocean Mission (DOM), which seeks to explore deep-sea resources for scientific and commercial purposes.
Upon successful execution, India will join an elite group of nations—including the United States, China, Russia, France, and Japan—that have developed crewed deep-sea submersibles. This achievement will enhance India’s global standing in oceanographic research and bolster its capabilities in harnessing the ocean’s vast potential for technological and economic advancements.
Samudrayaan represents a giant leap in India's deep-sea exploration, merging cutting-edge engineering with scientific curiosity. As the country moves closer to launching the crewed deep-submergence vehicle Matsya 6000, this mission promises to unveil the mysteries of the deep ocean, contributing to marine conservation, resource utilization, and scientific progress. The coming years will be crucial in shaping India’s deep-sea exploration capabilities, paving the way for new discoveries beneath the ocean’s depths.
What is Samudrayaan mission?
Samudrayaan is India’s first crewed deep-sea mission, conceptually similar to space missions but designed for oceanic exploration. The mission will deploy a state-of-the-art deep-sea submersible, Matsya 6000, which can carry three crew members to extreme depths while withstanding immense underwater pressure. This submersible will play a pivotal role in studying deep-sea biodiversity, mapping the ocean floor, and assessing the feasibility of deep-sea mining.
One of the most formidable challenges in deep-sea exploration is the enormous pressure at such depths—6,000 meters below the surface, where pressure is approximately 600 times greater than at sea level. To withstand these extreme conditions, Matsya 6000 is being constructed with a titanium alloy pressure hull, ensuring strength while keeping the vehicle lightweight.
Given that the mission involves human occupants, the submersible is equipped with advanced life-support systems, including oxygen generation and CO₂ scrubbing technologies to maintain breathable air, thermal insulation to counteract the extreme cold of deep-sea environments, and emergency life-support systems in case of unforeseen situations.
Navigation and communication
Underwater navigation presents a unique challenge due to the absence of GPS signals for Samudrayaan mission. Matsya 6000 will rely on inertial navigation systems, acoustic positioning systems, and sonar technology for obstacle avoidance. The communication with the surface will be facilitated through low-frequency radio waves and acoustic modems. Unlike surface vessels, deep-sea submersibles must navigate three-dimensional space efficiently.
Matsya 6000 will be equipped with thrusters and ballast systems, allowing it to ascend, descend, and maneuver effectively in the deep-sea environment. The use of high-energy-density batteries ensures a sustained power supply for prolonged missions. The Indian Ocean harbours vast polymetallic nodules, hydrothermal sulfides, and cobalt-rich crusts, containing valuable metals such as manganese, nickel, copper, and cobalt.
Samudrayaan will aid in the assessment of these resources, facilitating sustainable extraction strategies. Additionally, the deep ocean remains one of the least explored habitats on Earth. This mission aims to study deep-sea organisms and their adaptations to extreme conditions, explore potential applications in biotechnology and medicine, collect crucial data on ocean currents, thermal vents, and climate patterns, enhancing our understanding of climate change and marine ecosystems.
Global deep sea exploration efforts
Several nations have pioneered deep-sea exploration, significantly advancing our knowledge of oceanic depths
* United States: The Alvin submersible has explored hydrothermal vents and deep-sea ecosystems since the 1960s, contributing to the discovery of chemosynthetic life forms.
* China: The Fendouzhe submersible achieved a record-breaking depth of over 10,900 meters in the Mariana Trench in 2020, demonstrating cutting-edge deep-diving technology.
* Japan: The Shinkai 6500, operated by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), has been instrumental in studying deep-sea geology and marine life.
* Russia: The Mir submersibles have explored the Titanic wreck and the Arctic seabed, showcasing deep-diving capabilities in extreme environments.
* France: The Nautile submersible has been extensively used for underwater archaeological research and oceanographic studies.
These missions have collectively expanded our knowledge of deep-sea biodiversity, underwater geology, and potential resources, setting the foundation for future explorations. India’s Samudrayaan mission will further contribute to this global effort, uncovering the secrets of the deep ocean and positioning India as a key player in deep-sea research and technology.
(The author is an assistant professor in Physics, St Thomas College, Kozhencherry- Pathanmthitta, Kerala, former project scientist, National Centre for Coastal Research, government of India, Chennai; former project scientist, Centre for Atmospheric Sciences, IIT Delhi. )
Maritime