Chandrayaan-3: India's historic journey to the Moon's south pole

At 6:04 pm on 23 August 2023 the whole country held its breath — and then applause broke out in ISRO's control room. The "Vikram" lander of Chandrayaan-3 had touched down safely near the Moon's south pole. With that, India became the fourth country to make a soft landing on the Moon (after the Soviet Union, the United States and China) and the first in the world to land near its south pole.

Chandrayaan-3 at a glance

Why the south pole?

Near the Moon's south pole there are deep craters where sunlight has not reached for billions of years. Scientists believe water may be stored there as ice. In future that water could be used for drinking, for making oxygen and for making rocket fuel. That is why the world's space agencies want to reach this region — and India got there first. Chandrayaan-1's instruments had also helped find evidence of water molecules on the Moon; read the full list in ISRO's major missions.

Learning from Chandrayaan-2's failure

In 2019 the Chandrayaan-2 lander crashed in the final moments of its descent. ISRO learned from it and built Chandrayaan-3 with a "failure-based design" — that is, by thinking about everything that could go wrong. The landing zone was enlarged from 500 m × 500 m to about 4 km × 2.4 km, the lander's legs were strengthened, more fuel was carried and new sensors were added to measure speed. ISRO's chairman at the time was S. Somanath.

What did Chandrayaan-3 find?

• Sulphur confirmed: the Pragyan rover's laser instrument confirmed, for the first time on the spot, the presence of sulphur in the soil near the south pole. Aluminium, calcium, iron, chromium, titanium and oxygen were also found.
• Temperature: an instrument on Vikram found the surface at up to about 70 °C, but the temperature fell sharply just a few centimetres below.
• Pragyan's drive: the rover covered more than 100 metres on the Moon.
• Vikram's hop: on 3 September 2023 Vikram fired its engines, rose about 40 centimetres and landed again nearby — an important test for future missions that bring samples back from the Moon.

Did you know? The place where Vikram landed was named the "Shiv Shakti point", and the spot where the Chandrayaan-2 lander fell was called the "Tiranga point". 23 August is now celebrated every year as "National Space Day".

After the mission

Before the lunar night began, Vikram and Pragyan were put into "sleep mode", because at night the temperature falls more than 100 degrees below zero. They did not wake up again, but by then they had finished their work. Chandrayaan-3's propulsion module was later brought back from lunar orbit to an orbit around Earth — another new experiment. Read more about the Moon and the Sun in How eclipses happen.

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