NDTV Exclusive: Inside India's Ocean Research Vessel Sagar Manjusha

NDTV spent nearly 30 hours onboard India's ocean research vessel ORV Sagar Manjusha, witnessing live scientific experiments in the Arabian Sea and getting an inside look at how researchers study the ocean floor.

The vessel is operated under the National Institute of Ocean Technology and is among the five ocean research vessels used by India for marine studies. Though it is the oldest among them, scientists say it continues to play a crucial role in oceanographic surveys and data collection.

Speaking to NDTV, hydrographic engineer Raajesh explained that the ship houses multiple laboratories equipped with specialised instruments used to study the ocean's structure and resources.

One of the key devices onboard is the sub-bottom profiler, which sends sound waves to the ocean floor and receives returning signals. The data helps scientists determine whether the seabed surface is soft sediment or hard rock.

Researchers also deploy equipment like a gravity corer to extract samples from beneath the seabed. These samples, along with collected water data, are analysed to understand geological formations and possible resource deposits.

Another instrument onboard is the Acoustic Doppler Current Profiler (ADCP). The device measures the velocity and direction of ocean currents, helping scientists understand underwater flow patterns.

The vessel also deploys a CTD device (Conductivity, Temperature and Depth), which can operate up to 1,000 metres below the ocean surface. It records temperature, salinity and depth, allowing scientists to analyse the marine environment in detail.

In addition, nets are deployed at a speed of around two nautical miles to collect biological and sediment samples. These samples are later examined in onboard laboratories to identify possible mineral deposits, petroleum indicators or other marine resources.

Under the National Institute of Ocean Technology, India currently operates several ocean research vessels, including Sagar Manjusha, Sagar Tara, Sagar Nidhi, and Sagar Anveshika. Among them, Sagar Nidhi is the newest and most advanced vessel currently deployed for deep ocean research.