When Chandrayaan-3 lifted off from Sriharikota on July 14, 2023, at 2:35 PM, millions of Indians watched with pride as the LVM-3 rocket carried India’s dreams towards the Moon.

The mission’s goal was straightforward—land safely on the lunar surface, deploy a small rover, and conduct experiments on the Moon’s soil. On August 23, 2023, India made history by becoming only the fourth country to achieve a soft landing on the Moon, and the very first to touch down near the South Pole.

Here’s where things get really interesting.

While the lander and rover completed their work on the surface, the propulsion module that had carried them to the Moon kept orbiting quietly at about 150km above the lunar surface.

Nobody expected what would happen next. In October 2023, ISRO engineers performed a bold experiment—they fired the module’s engines in what’s called a Trans-Earth Injection manoeuver, essentially giving it a push that sent it on a path back toward Earth. This wasn’t part of the original plan, but our scientists saw an opportunity to learn something new.

Many thought that pushing a spacecraft away from the Moon would simply bring it straight back to Earth. But instead of returning directly, the Propulsion Module entered a huge, stretched-out orbit around Earth.

Picture this orbit as a long oval path, not a circular one. When the spacecraft completes one loop around this path, it comes very close to the Earth at one end, then travels all the way out to enormous distances at the other end before coming back again.

“When the spacecraft is near the Earth, our planet’s gravity pulls it strongly and makes it swing around quickly. But as it travels along the oval path moving away from the Earth, it goes farther and farther out, reaching distances of several lakh kilometres. At these extreme distances, the Earth’s gravity becomes much weaker because gravity weakens with distance. Meanwhile, as the spacecraft travels outward on this long oval path, it naturally moves into the region of space where the Moon orbits Earth. So even though it started by leaving the Moon’s vicinity, the shape of its orbit eventually carried it back toward the Moon’s neighbourhood again,” explained space analyst Girish Linganna.

Analysing this further, the expert says that at such far distances from Earth, the Moon’s gravity eventually became stronger than Earth’s weakening pull, and the spacecraft naturally drifted back into what scientists call the Moon’s ‘sphere of influence’.

“Think of it like being caught between two friends playing catch, except these friends are massive celestial bodies playing with gravity. On November 4, 2025, the spacecraft crossed this invisible boundary where the Moon’s pull became dominant again. Just two days later, on November 6, it completed its first flyby, passing within 3,740km of the Moon,” Linganna added.

The Indian Deep Space Network had tracked every moment of this move. On Tuesday, at exactly 11:18 PM IST, the spacecraft performed its second flyby, this time at a distance of 4,537km from the Moon. It is expected to leave the Moon’s sphere of influence on Friday, continuing its journey through space.

Experts point out that these flybys changed the spacecraft’s path dramatically. Its orbit expanded from one lakh by three lakh kilometers to a whopping 4.09 lakh by 7.27 lakh kilometers. Even its tilt changed from 34 degrees to 22 degrees, all because of the Moon’s gravitational nudges during these close passes.

Why it matters

Experts say that what makes this interesting is that the ISRO didn’t waste a single opportunity.

Instead of letting the propulsion module simply run out of fuel and become space debris, they turned it into a training ground for future missions. They learned how to track objects in deep space more accurately, how to predict paths when both Earth and Moon are pulling on a spacecraft, and most importantly, how to understand those tiny, annoying forces (called disturbance torques)—from solar radiation, uneven heating, and from variations in gravity—which could slowly knock a spacecraft off course.

Many other space agencies have performed gravity assist manoeuvres and flybys, but what’s remarkable here is that India has achieved this with leftover fuel from a mission that had already succeeded beyond expectations.

Indian scientists turned what could have been waste into a valuable learning experience, proving that Indian ingenuity and resourcefulness can transform ordinary success into extraordinary achievement.