News and Updates

Lunar Lander Lineup, Two Nations, Two Missions

Chandrayaan-3 (left) and Luna 25 (right) soar into space on their way to the Moon. Credit: ISRO, via SpaceRef, Roscosmos, via Reuters

Next week is shaping up to be a busy time for rocket launches, but also a very busy time for the Moon. For the first time in 54 years, there are two landers in orbit of the Moon at the same time. On August 16th, Russia’s Luna 25 spacecraft joined India’s Chandrayaan-3 in Lunar orbit. Both missions carry their own incredible historical weight. Luna 25 is the first Russian mission to the Moon since Luna 24 in 1976, and the first Russian mission launched to visit another world since Phobos-Grunt, which failed to leave Earth orbit back in 2011. Chandrayaan-3, similarly, marks a return to the Moon for India, following their previous mission in 2019, and a successful landing will mark a first for India. Both missions face their own challenges and carry their own share of risk, but if all goes right, we will see two missions touch down safely on the Lunar surface within days of each other – an event which has never happened before.

Luna 25’s development dates as far back as the 90s. Political and budgetary setbacks have continually plagued the mission, even the aforementioned failure of Phobos-Grunt marked a significant hurdle and subsequent rework of the mission. Luna 25, originally conceived as Luna-Glob, was meant to spearhead a line of robotic Russian missions to the Lunar south pole, notably the target of many programs today including the Artemis Program. Luna-Glob would perform initial characterization of the region, with an orbital component, a landing component, and several impactors. This would then be followed up with a rover, Luna-Glob 2, to further investigate the region. The next phase was Luna-Grunt, a rover and sample return program, and then Lunar Polygon, a complex robotic outpost consisting of landers and rovers, which would serve as an uncrewed science station and technological proving ground for eventual Russian crew missions to the Moon.

For many reasons, including shared hardware with Phobos-Grunt and simple budgetary problems, this did not pan out. Luna-Glob was reduced to simply a lander, no orbital elements or impactors, and rechristened to Luna 25. Luna 25’s development, even in its simplified state, has been a very slow road. Luna 25 had to share limited resources with other projects, such as the Russian Landing Platform that was to deliver ESA’s ExoMars2020 rover, now known as Rosalind Franklin, to the surface of Mars. This Landing Platform, named Kazachok, is no longer a part of ExoMars, and may never fly. Luna 25 has continued however, even with its assembly spread out over the course of a decade, and successfully launched aboard a Soyuz 2.1b rocket on August 10th.

There is concern regarding Luna 25’s quality assurance, which is shared with Russian spacecraft in general. This is in part due to Luna 25’s drawn out pathway to launch, but also due to an alarming string of issues which have occurred on other Russian Spacecraft. Notably, Nauka, the Russian lab which sent the ISS into a spin after docking in 2021, and coolant leaks which occurred on the Soyuz MS-22 and Progress 82 spacecrafts, resulting in the stranding of the MS-22, have generated warranted concern in Roscosmos’ quality assurance. After some speculation that Luna 25 and its Fregat kick-stage had failed to separate from the launch vehicle, Roscomos confirmed that Luna 25 had completed its Lunar Transfer Burn, and separated from Fregat. Now hanging in orbit, Luna 25 will attempt to land on the Moon, delivering a payload of scientific instruments, north of Boguslawsky crater, on August 21st. 

As this article was being finalized, news broke that Luna 25 experienced a complication during a planned maneuver to place it on its pre-landing orbit. This has since resulted in loss of contact with the spacecraft. Attempts to recover Luna 25 are underway, and Space Scout will provide updates as information becomes available.

Luna 25 in space, the Russian flag displayed on its golden thermal foil. Credit: Roscosmos

In comparison, India’s Chandrayaan Program seems remarkably fast. In the time Russia has spent conceptualizing and building Luna 25, ISRO not only launched its own robotic lunar program, but inaugurated the vehicles which have launched it. Chandrayaan-1 launched to lunar orbit back in 2008, riding the first PSLV-XL. The mission consisted primarily of an orbiter, but also carried an impactor, which was used to detect water on the lunar south pole near Shackleton Crater. Chandrayaan-2 launched in 2019 on an LVM3-M1 rocket, and is the largest Chandrayaan mission launched so far. Chandrayaan-2 consisted of an orbital element, which remains active to this day, and a lander, named Vikram, which carried a rover. Due to a software bug, Vikram crashed on the 6th of September, 2019. Chandrayaan-3, which launched on July 14th, 2023, is similar to 2 however does not include an orbiter. The Chandrayaan-3 lander, also named Vikram, has a propulsion module in place of an orbiter, and will use Chandrayaan-2 as a relay.

Vikram Impact Site Credit: NASA/GSFC/Arizona State University

Communication from ISRO was spotty after communication was lost with Chandrayaan-2. To those who watched coverage of the landing attempt, it was obvious that something had gone wrong, however the exact nature of the failure was poorly communicated. There were early reports that the lander had touched down in a tilted position, while others stated it had experienced a hard-landing and was destroyed. The hope was that NASA’s Lunar Reconnaissance Orbiter, which has provided detailed imagery of the Moon since 2009, would uncover what occurred with India’s first ever attempted Moon landing. LRO flew over the planned landing site of Chandrayaan-2 a week after its landing attempt on the 17th of September, but was unable to find the lander or the crater it may have left behind. LRO overflew the site again in October that year, but once again Vikram wasn’t spotted. Vikram, or rather its resulting impact, wasn’t found in LRO’s images until December 2nd.

Chandrayaan-3 before launch Credit: ISRO

Chandrayaan’s cause of failure has not been explained to a fine point, but what is understood is that the lander was unable to compensate for a growing deviation from the pre-planned trajectory, and became confused. ISRO has spent plenty of time planning, testing, and implementing changes to Vikram’s successor to increase its chances of success. During an Address by ISRO Chairman S. Somanath on the 5th of this month, these changes were highlighted. These include changes to softwares which manage thruster and gyroscope control, the implementation of enhanced guidance control, the ability to salvage a landing even if the lander diverts from its planned course, and the introduction of a new Laser Doppler Velocimeter, which upgrades the lander’s ability understand its condition during the landing phase. Simulations of all the software aboard the spacecraft were emphasized in the last few years, ensuring Vikram will be able to guide itself to a safe landing even if things do not go precisely as planned, and testing of the craft’s various sensors has taken place. If ISRO’s work pays off, Chandrayaan-3 will touch down on the Moon on the 23rd of August, and India will become the fourth country to ever soft-land on the lunar surface.

The landing attempts to come this week are an exhilarating example of the increased focus the Moon has received in recent years, and will continue to receive. Even this year, Japanese Startup iSpace had their first attempted landing on the Moon, which ended in a failure a few months ago, and Innovative Machines is booked to launch their Nova-C lander later this year. Space Scout will be keeping a close eye on both landers in order to provide accurate information on the outcomes of their missions in a future article.

UPDATE: Yesterday, at 8:47 AM UTC, Roscosmos officially declared that the Luna 25 spacecraft had been lost. Roscosmos head Yuri Borisov further clarified that during the maneuver to direct Luna 25 towards its prelanding orbit, the spacecraft’s engines fired for 127 seconds instead of the intended 84. As a result, instead of simply lowering its orbit around the Moon, Luna 25 deorbited itself and crashed into the Lunar surface. The location of the impact site is not known at this time.

Edited By Beverly and Nik Alexander

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.