Chandrayaan-4: India’s Moon Sample-Return Mission Explained

Chandrayaan-4 is a planned lunar sample-return mission of the Indian Space Research Organisation (ISRO), approved by the Government of India in 2024, which aims to land on the Moon, collect lunar soil and rocks and bring them safely back to Earth. If it succeeds, India will join the small group of countries that have returned samples from the Moon, a feat so far achieved by the United States, the Soviet Union and China.

The mission is much more complex than Chandrayaan-3, which only landed on the Moon. Chandrayaan-4 requires several separate spacecraft modules, two launches, docking in space and a return journey, and it is described here as an approved and planned mission rather than one that has flown. 15 October 2026

Key Takeaways

• Chandrayaan-4 is ISRO’s approved lunar sample-return mission, cleared by the Government of India in 2024, and its goal is to bring Moon samples back to Earth.
• The Chandrayaan-4 spacecraft is made up of four modules, called the Descender, Ascender, Transfer and Re-entry modules, each with a distinct role.
• The mission plans to use two launches, one on the heavy-lift LVM3 rocket and one on the Polar Satellite Launch Vehicle (PSLV), because no single Indian launcher can carry the full set of modules.
• Chandrayaan-4 depends on in-space docking, a capability that ISRO demonstrated with the Space Docking Experiment (SpaDeX) between late 2024 and early 2025.
• Only the United States, the Soviet Union and China have so far returned samples from the Moon, so a successful Chandrayaan-4 would make India the fourth country to do so.
• Chandrayaan-4 builds on the soft landing achieved by Chandrayaan-3 in August 2023 and supports India’s longer-term goal of landing an Indian astronaut on the Moon.

What is Chandrayaan-4?

Chandrayaan-4 is the fourth mission in India’s Chandrayaan lunar exploration series, and it is designed to demonstrate the technologies needed to bring samples from the Moon back to Earth. The earlier missions were an orbiter, an orbiter with a lander and rover, and a lander with a rover. Chandrayaan-4 adds the return leg.

The word “Chandrayaan” means “Moon vehicle” in Sanskrit. ISRO, which is headquartered in Bengaluru and operates under the Department of Space, has described Chandrayaan-4 as a mission that tests the full chain of operations: landing, sampling, lifting off from the Moon, meeting another spacecraft in lunar orbit, and returning to Earth.

Planning documents describe a lander-based approach rather than a crewed mission. The samples are expected to be a small quantity, on the order of a couple of kilograms, collected from the surface and from below it using a drilling or scooping tool, but the final figures will depend on the finished design.

Why is a lunar sample-return mission important?

A lunar sample-return mission is important because samples brought to Earth can be studied in laboratories with instruments far more precise than anything that can be carried to the Moon. Analysing real lunar material reveals the age, composition and history of the Moon, and it also helps to understand the early Solar System.

• Scientific value: Laboratory analysis can date rocks and identify trace elements, isotopes and volatiles such as water ice.
• Technology value: The mission tests landing, ascent, docking and re-entry, all of which are needed for future crewed missions.
• Strategic value: Few countries have such a capability, and it boosts national space credentials.
• Industrial value: A complex mission stimulates the aerospace supply chain and trains engineers.

The Apollo missions of the United States returned a large collection of lunar material between 1969 and 1972, and the Soviet Union’s robotic Luna missions returned smaller samples in the 1970s. China’s Chang’e-5 mission returned samples in 2020, and its Chang’e-6 mission in 2024 brought back the first samples from the far side of the Moon.

How was Chandrayaan-4 approved?

Chandrayaan-4 was approved by the Union Cabinet of India in 2024 as part of a set of space programme decisions. The approval authorised funding for the development of the spacecraft, launch and the demonstration of the technologies needed for sample return.

The approval reflected a long-term strategy set out by the Indian government for the space sector. Under that strategy, India aims to establish its own space station, the Bharatiya Antariksh Station, by the 2030s and to land an Indian on the Moon by 2040. Chandrayaan-4 is regarded as an important step toward those goals because it develops the skills needed to move people and cargo between the Moon and Earth.

The target launch date has been indicated as being later in the 2020s. As with any complex space mission, schedules can change as design and testing progress.

What are the modules of Chandrayaan-4?

The modules of Chandrayaan-4 are the Descender Module, the Ascender Module, the Transfer Module and the Re-entry Module. Each has a specific job in the sequence from launch to return, and together they form a relay in which the samples change vehicles several times.

In this architecture the Descender and Ascender act together as a lunar lander and ascent vehicle. The Transfer and Re-entry modules remain in orbit, waiting for the samples. Splitting the mission into modules makes each vehicle lighter and simpler, but it requires reliable operations in space between the vehicles.

How will Chandrayaan-4 work, step by step?

Chandrayaan-4 will work as a sequence of stages in which the lander descends to the Moon, collects samples, sends them up to an orbiting vehicle and then returns them to Earth. The steps below describe the mission as publicly outlined, and details may be refined as design work continues.

• Launch: Two separate launches carry the modules into space, one by LVM3 and one by PSLV.
• Journey to the Moon: The modules travel to lunar orbit, with the Transfer Module supplying propulsion.
• Landing: The Descender, with the Ascender attached, separates and makes a soft landing near the chosen site.
• Sampling: The mission collects lunar soil and rock using robotic equipment and stores them in the Ascender.
• Ascent: The Ascender lifts off from the Descender and climbs back into lunar orbit.
• Rendezvous and docking: The Ascender meets the orbiting Transfer and Re-entry stack, and they dock so that the sample container can be moved across.
• Return: The Transfer Module fires its engine to leave lunar orbit and heads for Earth.
• Re-entry: The Re-entry Module separates, passes through the atmosphere using a heat shield and parachutes, and the samples are recovered.

Each step carries risk. The landing and the liftoff from the Moon are particularly demanding because there is no launch pad, no support crew and no second chance, and the vehicle must operate autonomously.

Why does Chandrayaan-4 need two launches?

Chandrayaan-4 needs two launches because the total mass of its modules is too large for a single Indian rocket to send to the Moon, so ISRO plans to divide the modules between an LVM3 and a PSLV. The mission design assumes that the lander-related hardware and the return-related hardware are launched separately and brought together in space.

The Launch Vehicle Mark-3 (LVM3) is ISRO’s heaviest operational rocket. It launched Chandrayaan-3 in 2023 and is the vehicle selected for the heavier part of the mission. The Polar Satellite Launch Vehicle (PSLV) is a smaller and well-proven workhorse that has flown many missions, including the SpaDeX docking demonstration.

The alternative to two launches would be a much larger rocket, such as the Next Generation Launch Vehicle that ISRO is developing for later missions. By using existing launchers, ISRO can fly the mission sooner and at lower cost, although the strategy places greater demands on in-space docking.

What is docking, and how does SpaDeX help?

Docking is the process of bringing two spacecraft together in orbit and joining them mechanically, electrically and sometimes for the exchange of fuel or cargo. Chandrayaan-4 depends on this technology because its modules must meet and connect in space, and because the samples must be transferred from one vehicle to another.

ISRO tested the technology in the Space Docking Experiment (SpaDeX), launched on a PSLV in December 2024. SpaDeX used two small satellites, which approached each other and successfully docked in January 2025, making India the fourth country to demonstrate in-space docking after the United States, Russia and China. The satellites later undocked and carried out further experiments, including power transfer between them.

SpaDeX was an Earth-orbit test, and docking around the Moon is harder, since the distances are greater and communication delays and navigation challenges increase. Even so, SpaDeX gave ISRO flight data on rendezvous, sensors, control and docking mechanisms that feed directly into the Chandrayaan-4 design.

Where will Chandrayaan-4 land?

Chandrayaan-4 is planned to land near the south-polar region of the Moon, an area that has attracted global scientific attention since Chandrayaan-3 landed in the same broad region in 2023. The exact site has not been fixed in public documents, and reports have discussed the vicinity of Chandrayaan-3’s landing area as one candidate.

The south-polar region is interesting for several reasons. Some craters near the poles never receive sunlight, and they can trap water ice and other volatile compounds that may be preserved for billions of years. Such material would help to understand the origin of water in the Solar System and could support future human missions.

The region is also hard to operate in. Sunlight arrives at very low angles, terrain is rugged and temperatures can drop extremely low in shadow, so the mission requires precise navigation and careful choice of a safe, sunlit landing zone.

How does Chandrayaan-4 build on earlier Chandrayaan missions?

Chandrayaan-4 builds on earlier Chandrayaan missions by reusing lessons in orbit insertion, soft landing and surface operations while adding new capabilities for sampling and return. Each mission in the series has extended India’s lunar capability in a stepwise manner.

Chandrayaan-3 made India the fourth country to soft-land on the Moon, after the Soviet Union, the United States and China, and the first to do so near the south pole. The soft-landing technology developed for that mission is the base for the Chandrayaan-4 lander, but the new mission must also handle liftoff and docking.

How does Chandrayaan-4 connect to India’s future space goals?

Chandrayaan-4 connects to India’s future space goals by testing the technologies required for crewed lunar missions, namely landing, ascent, rendezvous and safe re-entry. India has stated an ambition to land an Indian astronaut on the Moon by 2040.

The Gaganyaan programme, India’s human spaceflight effort to low Earth orbit, forms one pillar of that effort. The planned Bharatiya Antariksh Station forms another. Chandrayaan-4 adds the capability to operate at the Moon and return material to Earth.

The mission also fits into international lunar cooperation. India has been a signatory to the Artemis Accords, and it has discussed a joint lunar polar exploration mission with Japan’s space agency, JAXA. Such partnerships can share costs and expertise, though Chandrayaan-4 itself is principally an Indian mission.

What challenges could Chandrayaan-4 face?

Chandrayaan-4 could face challenges in precision landing, lunar liftoff, docking in lunar orbit and safe re-entry, because each is a complex technology that has to work without failure. A shortfall in any one stage could end the mission.

• Landing accuracy: The lander must find a safe site in rough terrain with limited lighting.
• Ascent from the Moon: The Ascender must lift off reliably after surviving the lunar environment.
• Docking in lunar orbit: Autonomous rendezvous and docking at lunar distance is harder than in Earth orbit.
• Re-entry: The Re-entry Module must withstand very high speeds and temperatures when it returns from lunar distance.
• Sample handling: The samples must be sealed, stored and protected from contamination.
• Schedule and cost: Multi-launch missions need careful coordination, and delays are possible.

ISRO has addressed some risks through experience with Chandrayaan-3 and SpaDeX, and it can also use ground testing and simulations. Even so, the first attempt at a sample return will test the organisation’s engineering depth.

Bottom Line

Chandrayaan-4 is an approved, planned ISRO mission to collect Moon samples and return them to Earth using four modules, two launches and in-space docking. If it succeeds, India will become the fourth country to achieve a lunar sample return and will move closer to its goal of a crewed Moon landing.

Frequently Asked Questions

What is Chandrayaan-4?

Chandrayaan-4 is a planned lunar sample-return mission of ISRO that aims to land near the Moon’s south-polar region, collect samples and bring them back to Earth. It was approved by the Government of India in 2024 and has not yet launched.

Which modules make up Chandrayaan-4?

Chandrayaan-4 has four modules: the Descender, the Ascender, the Transfer Module and the Re-entry Module. The Descender lands, the Ascender carries samples back to orbit, the Transfer Module provides propulsion for the journey, and the Re-entry Module returns the samples through Earth’s atmosphere.

Why does Chandrayaan-4 need two launches?

Chandrayaan-4 needs two launches because the combined weight of its modules is too great for one Indian launcher. ISRO plans to use an LVM3 and a PSLV, with the modules meeting and docking in space.

How is Chandrayaan-4 different from Chandrayaan-3?

Chandrayaan-4 differs from Chandrayaan-3 because it is designed to return samples to Earth, while Chandrayaan-3 only landed and operated on the lunar surface. Chandrayaan-4 adds lunar liftoff, docking and Earth re-entry to the landing capability proven in 2023.

What is SpaDeX and why does it matter for Chandrayaan-4?

SpaDeX, or the Space Docking Experiment, was an ISRO mission launched in December 2024 that demonstrated docking between two small satellites in Earth orbit in January 2025. It matters for Chandrayaan-4 because the sample-return mission needs spacecraft to dock and transfer samples in space.

Which countries have returned samples from the Moon?

The United States, the Soviet Union and China have returned samples from the Moon. A successful Chandrayaan-4 would make India the fourth country to do so.

{“@context”:”https://schema.org”,”@graph”:[{“@type”:”FAQPage”,”mainEntity”:[{“@type”:”Question”,”name”:”What is Chandrayaan-4?”,”acceptedAnswer”:{“@type”:”Answer”,”text”:”Chandrayaan-4 is a planned lunar sample-return mission of ISRO that aims to land near the Moon’s south-polar region, collect samples and bring them back to Earth. It was approved by the Government of India in 2024 and has not yet launched.”}},{“@type”:”Question”,”name”:”Which modules make up Chandrayaan-4?”,”acceptedAnswer”:{“@type”:”Answer”,”text”:”Chandrayaan-4 has four modules: the Descender, the Ascender, the Transfer Module and the Re-entry Module. The Descender lands, the Ascender carries samples back to orbit, the Transfer Module provides propulsion for the journey, and the Re-entry Module returns the samples through Earth’s atmosphere.”}},{“@type”:”Question”,”name”:”Why does Chandrayaan-4 need two launches?”,”acceptedAnswer”:{“@type”:”Answer”,”text”:”Chandrayaan-4 needs two launches because the combined weight of its modules is too great for one Indian launcher. ISRO plans to use an LVM3 and a PSLV, with the modules meeting and docking in space.”}},{“@type”:”Question”,”name”:”How is Chandrayaan-4 different from Chandrayaan-3?”,”acceptedAnswer”:{“@type”:”Answer”,”text”:”Chandrayaan-4 differs from Chandrayaan-3 because it is designed to return samples to Earth, while Chandrayaan-3 only landed and operated on the lunar surface. Chandrayaan-4 adds lunar liftoff, docking and Earth re-entry to the landing capability proven in 2023.”}},{“@type”:”Question”,”name”:”What is SpaDeX and why does it matter for Chandrayaan-4?”,”acceptedAnswer”:{“@type”:”Answer”,”text”:”SpaDeX, or the Space Docking Experiment, was an ISRO mission launched in December 2024 that demonstrated docking between two small satellites in Earth orbit in January 2025. It matters for Chandrayaan-4 because the sample-return mission needs spacecraft to dock and transfer samples in space.”}},{“@type”:”Question”,”name”:”Which countries have returned samples from the Moon?”,”acceptedAnswer”:{“@type”:”Answer”,”text”:”The United States, the Soviet Union and China have returned samples from the Moon. A successful Chandrayaan-4 would make India the fourth country to do so.”}}]}]}