ORV Sagar Manthan — Yard 3041 — entered the water at the Rishi Bankim Shipyard, Kolkata, on 9 September 2026. It is India's first advanced Ocean Research Vessel designed and built in India, constructed by the defence shipyard Garden Reach Shipbuilders and Engineers (GRSE) for the National Centre for Polar and Ocean Research (NCPOR) under the Ministry of Earth Sciences. Union Minister Dr Jitendra Singh launched it virtually; his spouse Mrs Manju Singh named the ship, by tradition. Ministry Secretary Dr T. Srinivasa Kumar was present at Kolkata.
A ship launch is not a commissioning — that distinction alone is worth a mark. This piece sets out what the vessel is, what it will do, and the mission it belongs to.
Launch is not commissioning
At a launch, a hull is transferred into the water so that the next stage of building can begin. What follows is superstructure erection, system integration and sea trials; only then is the ship delivered and commissioned. Sagar Manthan's delivery to NCPOR is scheduled for 2028.
The build timeline the Minister praised runs: contract signed July 2024, first steel cut 29 November 2024, keel laid 8 April 2026, launched 9 September 2026 — a launch within about two years of contract and roughly five months of keel-laying. The keel is the ship's spine, the first structural member laid down; keel-laying is the formal start of construction.
What the ship carries
Built at about ₹840 crore, Sagar Manthan is an all-weather, multidisciplinary platform engineered for extreme seas including the Southern Ocean, with a design life of 30 years. Its equipment list is the exam-relevant part:
- Dynamic positioning — thrusters and satellite navigation that hold a ship stationary over a point on the seabed without anchoring, essential in deep water.
- Multibeam bathymetry — sonar that maps the shape of the seafloor in a wide swath rather than a single line.
- Multichannel seismic systems and sub-bottom profiling — acoustic methods that image the sediment and rock layers beneath the seabed.
- Drop keels — retractable fins that carry sensors below the hull, clear of its own bubble wake and noise.
- Handling systems for Remotely Operated Vehicles (ROV) and Autonomous Underwater Vehicles (AUV) — tethered and untethered robotic submersibles.
- Weather radar and upper-air observation, and CTD profiling — Conductivity, Temperature, Depth, the standard instrument for measuring the ocean's salinity and temperature with depth. Why salinity and temperature matter for currents is set out on the ocean currents and tides page.
Its scientific target is the mid-oceanic ridges of the Indian Ocean, where it will look for multi-metal hydrothermal sulphide mineralisation — the metal-rich deposits that form where seawater circulates through hot volcanic crust at spreading ridges and precipitates copper, zinc, gold and silver around hydrothermal vents. It will also establish environmental baselines, which is the measurement of an undisturbed seabed against which any future mining impact can be judged. The ridge system itself is explained on the ocean relief page.
The vessel is certified under dual class by the Indian Register of Shipping and the American Bureau of Shipping — classification societies that set and verify construction standards for ships.
The ship it replaces
ORV Sagar Kanya was built in Germany under Indo-German collaboration and delivered in 1983; at 43 years old it is the workhorse that carried Indian oceanography for four decades, and Sagar Manthan will gradually take over from it. The Minister said more oceanographic vessels and a dedicated Polar Research Vessel are planned.
India's research fleet is worth knowing as a set: Sagar Kanya and Sagar Nidhi (bought from Italy in 2007, ice-strengthened, operated by the National Institute of Ocean Technology, Chennai), Sagar Sampada for fishery and oceanographic research, and the chartered ships that carry the Indian Antarctic expeditions.
NCPOR, at Vasco da Gama, Goa, was set up on 25 May 1998 as the National Centre for Antarctic and Ocean Research and renamed in 2018. It runs India's polar programme — the Antarctic stations Maitri (1989) and Bharati (2012), after the abandoned Dakshin Gangotri (1983), the Arctic station Himadri at Ny-Ålesund, Svalbard (2008), and the Himalayan station Himansh in Spiti.
GRSE itself began in 1884 as a river workshop on the Hooghly, became Garden Reach Workshop in 1916 and was taken over by the government in 1960; it is one of India's principal defence shipyards, having delivered more than 100 warships.
The Deep Ocean Mission
Sagar Manthan is built under Vertical 4 — Deep Ocean Survey and Exploration of the Deep Ocean Mission, approved by the Cabinet in June 2021 at ₹4,077 crore over five years, under the Ministry of Earth Sciences. Its six components are:
- Technologies for deep-sea mining and a manned submersible — the Samudrayaan project and Matsya-6000, designed by the National Institute of Ocean Technology to carry three people to 6,000 metres.
- Ocean climate change advisory services — models for a decadal-scale forecast.
- Technological innovations for deep-sea biodiversity exploration and conservation.
- Deep-ocean survey and exploration — the pillar that funded this ship.
- Energy and freshwater from the ocean — including Ocean Thermal Energy Conversion and desalination.
- An advanced marine station for ocean biology.
Behind the mission lies a legal fact: India holds an exclusive contract from the International Seabed Authority to explore polymetallic nodules in the Central Indian Ocean Basin, first signed in 1987, which made India the world's first "pioneer investor", and a later contract for polymetallic sulphides on the Indian Ocean ridges. The mission is also a pillar of the Blue Economy in the government's Vision for 2030. For the broader science and technology GK this belongs to, the NDA study material hub is the base.
🔑 Revision block
The event. ORV Sagar Manthan launched 9 September 2026, Rishi Bankim Shipyard, Kolkata; built by GRSE for NCPOR under the Ministry of Earth Sciences; launched virtually by Dr Jitendra Singh; delivery due 2028. The ship. ~₹840 crore; all-weather, Southern Ocean capable; 30-year design life; dynamic positioning, multibeam bathymetry, multichannel seismic, sub-bottom profiling, drop keels, ROV and AUV handling, weather radar, CTD; dual class — Indian Register of Shipping and American Bureau of Shipping. Milestones. Contract July 2024; first steel 29 November 2024; keel laid 8 April 2026; launched 9 September 2026. Mission target. Indian Ocean mid-oceanic ridges; multi-metal hydrothermal sulphides; environmental baselines. Predecessor. ORV Sagar Kanya — built in Germany, delivered 1983, 43 years old; Sagar Nidhi (Italy, 2007, NIOT); Sagar Sampada; a Polar Research Vessel planned. NCPOR. Vasco da Gama, Goa; established 25 May 1998 (as NCAOR); stations — Maitri (1989), Bharati (2012), Dakshin Gangotri (1983, abandoned), Himadri (Svalbard, 2008), Himansh (Spiti). Deep Ocean Mission. June 2021, ₹4,077 crore, Ministry of Earth Sciences; six components; Samudrayaan and Matsya-6000 (3 crew, 6,000 m, by NIOT); India a pioneer investor at the International Seabed Authority since 1987 for Central Indian Ocean Basin nodules. GRSE. Kolkata, from 1884; defence shipyard.
🎯 Practice MCQs
Q1. ORV Sagar Manthan is being built for: (a) the Indian Navy (b) NCPOR, under the Ministry of Earth Sciences (c) ISRO (d) the Indian Coast Guard → (b).
Q2. The shipyard building ORV Sagar Manthan is: (a) Mazagon Dock (b) Cochin Shipyard (c) Garden Reach Shipbuilders and Engineers (d) Hindustan Shipyard → (c) — Kolkata.
Q3. The Deep Ocean Mission was approved in: (a) 2018 (b) 2019 (c) 2021 (d) 2023 → (c) — June 2021, ₹4,077 crore.
Q4. Matsya-6000, India's manned submersible, is designed to carry: (a) one person to 3,000 m (b) three persons to 6,000 m (c) five persons to 6,000 m (d) three persons to 11,000 m → (b).
Q5. ORV Sagar Kanya was procured in 1983 from: (a) Norway (b) Italy (c) Germany (d) Japan → (c).
Q6. CTD profiling on a research vessel measures: (a) seabed magnetism (b) conductivity, temperature and depth of the water column (c) atmospheric carbon (d) fish stocks → (b).
Q7. Multibeam bathymetry is used to: (a) drill the seabed (b) map the shape of the seafloor (c) measure wave height (d) track cyclones → (b).
Q8. India's Arctic research station is: (a) Maitri (b) Bharati (c) Himadri (d) Himansh → (c) — at Ny-Ålesund, Svalbard.
Q9. NCPOR is headquartered at: (a) Chennai (b) Kochi (c) Goa (d) Visakhapatnam → (c) — Vasco da Gama.
Q10. Hydrothermal sulphide deposits are typically found at: (a) continental shelves (b) mid-oceanic ridges (c) deep-sea trenches (d) coral atolls → (b).
Q11. The keel-laying of a ship marks: (a) its delivery (b) its commissioning (c) the formal start of its construction (d) its first sea trial → (c).
Q12. Consider the following: 1. India explores polymetallic nodules in the Central Indian Ocean Basin under a contract with the International Seabed Authority. 2. Matsya-6000 is being developed by ISRO. (a) 1 only (b) 2 only (c) Both (d) Neither → (a) — Matsya-6000 is from the National Institute of Ocean Technology.
📋 How this gets asked (PYQ pattern)
Ocean-science questions come in four shapes. The ministry item — which ministry runs the Deep Ocean Mission, NCPOR or NIOT, with Space and Science & Technology as the planted errors. The station item — Maitri, Bharati, Himadri and Himansh matched to Antarctica, the Arctic and the Himalaya. The technology item — what a submersible, an AUV, an ROV or a CTD does. The resource item — polymetallic nodules and the Central Indian Ocean Basin, or sulphides at ridges.
The fresh 2026 hook is Sagar Manthan as India's first home-built ocean research vessel and the ship it replaces; expect a statement pair on the builder and the owner. We describe the recurring pattern, not any exact past question.
Preparing for NDA? Ocean science pays twice — once in general science, once in geography. Build the base with our NDA study material hub, follow the daily NDA current affairs, and train with our ex-officer faculty in the upcoming Cavalier courses in Delhi.
✍️ Written by Col Vijyanat Thakur — Defence & security faculty at The Cavalier. Reviewed by the Cavalier Faculty Desk. The Cavalier, founded by ex-Army officers, has trained NDA/CDS/SSB aspirants since 2001 (Facebook · YouTube).
Source: PIB / Ministry of Earth Sciences, 9 September 2026. Vessel specifications, mission structure and institutional history cross-verified with NCPOR, GRSE and independent sources.