Chandrayaan-3 updates: As Chandrayaan-3 entered its penultimate stage before making a soft landing on the Lunar south pole next week, the race between the Indian spacecraft and Russia's Luna-25 has gained momentum.
On Friday, the Indian Space Research Organisation (ISRO) said Chandrayaan-3's Lander Module successfully descended to a slightly lower orbit as per the 'deboosting' schedule planned.
On August 17, the Vikram lander module successfully separated from the propulsion module, ISRO stated.
In comparison, Russia's lunar mission, Luna-25, successfully reached the lunar orbit on August 16, as per the Russian space agency Roscosmos' statement.
According to Roscosmos, the Russian spacecraft is likely to land on the moon on Monday — two days before Chandrayaan-3.
While Chandrayaan-3 was launched on July 14 from Satish Dhawan Space Centre, Russia successfully launched its inaugural moon-landing spacecraft on August 11 from Russia's Vostochny spaceport aboard Soyuz 2.1v rocket.
Also read: Chandrayaan-3: Lander Vikram's second deboosting tomorrow; to reach destination by Aug 23
Luna-25 will complete the journey in 10 days on Monday, as compared to Chandrayaan-3’s 38 days.
This is because Luna-25 is taking a more direct trajectory to the Moon than Chandrayaan-3. The Indian craft is guided largely by the gravitational forces of the Earth and the moon.
Also read: Chandrayaan-3: India surpasses China in active spacecraft around Moon
Touchdown for Luna 25 and Chandrayaan-3
On August 18, Russia's Luna-25 spacecraft adjusted its orbit as it is preparing to attempt the first landing near the south pole of the moon on August 21, space agency Roscosmos said.
"Today at 09:20 Moscow time (0620 GMT), the propulsion system of the automatic station performed an orbit correction lasting 40 seconds. Its goal is to provide the best conditions for the subsequent construction of a pre-landing orbit," Roscosmos said in a statement.
On the other hand, the Lander Module of Chandrayaan-3, comprising Vikram lander and Pragyan rover, will undergo its second deboosting operation on August 20.
The first deboosting operation was done on August 18.
Following this, the lander will attempt to make a landing on the lunar surface on August 23. After the lander touches down on the moon's surface, the Pragyan rover will be rolled down, marking the beginning of 14 Earth Day planned scientific exploration.
A key factor in the differing arrival times of the two missions is their respective mass and fuel efficiency.
Luna-25 has a leaner lift-off mass of only 1,750 kilograms, significantly lighter than Chandrayaan-3's 3,800 kg.
This reduced mass allows Luna-25 to accelerate more effectively, according to India's space agency ISRO.
Landing spots
Both missions are aiming to land in a region where no spacecraft has gone before, near the South Pole of the Moon. Though both the missions are targeting to make landings near the South Pole, the landing sites are not exactly in the polar region on the Moon, as per reports.
The selected site for Chandrayaan-3 is about 68 degrees South latitude while that of Luna 25 is closer to 70-degree South.
The actual distance between the two landing sites can be several hundred kilometres on the lunar surface, hence both spacecraft must capture different aspects of the Moon's soil.
The Luna-25 mission aims to study the composition of the moon's surface and the plasma and dust that make up its thin atmosphere over a year-long expedition.
Chandrayaan-3, on the other hand, is carrying six payloads that would help ISRO understand the lunar soil and also click pictures of the Earth from the moon's orbit.
Also watch: Historic Lunar missions before Chandrayaan-3 and their significance in space exploration
Will the race make a difference?
Chrisphin Karthick, a scientist at Bangalore's Indian Institute of Astrophysics, told PTI: “In the grand scope of cosmic exploration, the order of arrival may not significantly alter the lunar landscape. Yet, the knowledge gained from each mission will enrich our understanding of the Moon's past and potential. The value lies in the sum of our combined efforts."
ISRO head S Somanath has said that even in the event of non-functioning sensors and two engines, the lunar lander Vikram from India's third lunar mission, Chandrayaan-3, is capable of achieving a gentle touchdown on the Moon's surface come August 23.
As the world is keenly watching the historic landings of both spacecraft, both missions are expected to provide groundbreaking insights into the Moon's composition, history and potential as a resource-rich body.
(With agency inputs)
Also read: Chandrayaan-3 update: ISRO releases images of the Moon captured by Vikram lander
Also read: Russia's Luna-25 spacecraft enters lunar orbit, touchdown planned two days ahead of Chandrayaan-3