The orbital propulsion module for India’s Chandrayaan-3 lunar lander drifts back into lunar orbit
When India’s Chandrayaan-3 spacecraft arrived in lunar orbit in August 2023, it separated into three units, the lander, a lunar orbiter, and a propulsion unit used to get everything to the Moon.
While the Vikram lander successfully touched down several hundred miles from the Moon’s south pole and the Chandrayaan-3 orbiter continues to make observations of the Moon, in October 2023 engineers had the propulsion module do a burn that sent it out of lunar orbit and into an Earth orbit that was close to one of the Lagrange points where the gravity of the Earth and Moon are balanced.
Now, three years later, that module has drifted back into lunar orbit, where it has since done two close fly-bys of the surface.
This intricate orbital dance culminated when the module once again entered the Moon’s SOI [sphere of influence] on November 4, 2025, an event marking the transition where lunar gravity dominates its motion.
The first recorded lunar flyby occurred on November 6, 2025, at a distance of 3,740 km from the lunar surface, though it was outside the Indian Deep Space Network’s (IDSN) visibility range. A second, closely monitored flyby took place on November 11, 2025, bringing the module within 4,537 km of the Moon and well within observation capabilities.
These events noticeably altered the satellite’s orbital parameters, expanding its orbit size from 100,000 x 300,000 km to a massive 409,000 x 727,000 km and shifting its inclination from 34° to 22°.
It is not clear what happens next. Having this module in lunar orbit could be an issue for present and later orbiters, as no orbit around the Moon can ever be stable. At some point India’s space agency ISRO needs to properly dispose of this unit, either by sending into the Moon or out of the Moon-Earth system entirely. I am of course assuming it has the fuel to do so.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
When India’s Chandrayaan-3 spacecraft arrived in lunar orbit in August 2023, it separated into three units, the lander, a lunar orbiter, and a propulsion unit used to get everything to the Moon.
While the Vikram lander successfully touched down several hundred miles from the Moon’s south pole and the Chandrayaan-3 orbiter continues to make observations of the Moon, in October 2023 engineers had the propulsion module do a burn that sent it out of lunar orbit and into an Earth orbit that was close to one of the Lagrange points where the gravity of the Earth and Moon are balanced.
Now, three years later, that module has drifted back into lunar orbit, where it has since done two close fly-bys of the surface.
This intricate orbital dance culminated when the module once again entered the Moon’s SOI [sphere of influence] on November 4, 2025, an event marking the transition where lunar gravity dominates its motion.
The first recorded lunar flyby occurred on November 6, 2025, at a distance of 3,740 km from the lunar surface, though it was outside the Indian Deep Space Network’s (IDSN) visibility range. A second, closely monitored flyby took place on November 11, 2025, bringing the module within 4,537 km of the Moon and well within observation capabilities.
These events noticeably altered the satellite’s orbital parameters, expanding its orbit size from 100,000 x 300,000 km to a massive 409,000 x 727,000 km and shifting its inclination from 34° to 22°.
It is not clear what happens next. Having this module in lunar orbit could be an issue for present and later orbiters, as no orbit around the Moon can ever be stable. At some point India’s space agency ISRO needs to properly dispose of this unit, either by sending into the Moon or out of the Moon-Earth system entirely. I am of course assuming it has the fuel to do so.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
How can it stay in lunar orbit with an orbit that large? Am I missing something?