Race to Moon: Chandrayaan-3’s Vikram lander set to detach today; Luna-25 makes lunar orbit entry

Chandrayaan-3, the Indian Space Research Organisation (ISRO) lunar mission, has achieved a nearly circular orbit around the Moon.

This comes after a successful manoeuvre on Wednesday, which positioned the spacecraft into a lunar orbit of 153*163km. Today, the Vikram lander is set to detach from the propulsion module.

As Chandrayaan-3 continues to draw closer to its targeted lunar touchdown, another contender in lunar exploration, Luna-25, the Russian lunar mission launched just last week, has successfully entered lunar orbit and is gearing up for a soft landing attempt on the lunar surface between August 21 and 23. This timing potentially positions Luna-25 ahead of Chandrayaan-3’s planned touchdown on August 23.

In an official statement published in Russian on Wednesday, Roscosmos said, “Luna-25 has entered the orbit of an artificial moon satellite! This was provided by two inclusions of the propulsion system of the automatic station. The first activation was performed by a corrective braking engine and lasted 243 seconds, the second by soft landing engines and lasted 76 seconds.”

In the upcoming days, Luna-25 is projected to orbit Earth’s only natural satellite for approximately five days before redirecting its course toward a targeted soft landing on the lunar south pole, scheduled for August 21.

Roscosmos said that all systems aboard Luna-25 are performing optimally, with stable communication. Regular sessions are underway to assess the current navigational parameters of the spacecraft.

Chandrayaan-3 status update:

Continuing its journey towards a lunar landing, the Chandrayaan-3 executed its fifth and final lunar-bound orbit manoeuvre, positioning itself even closer to the Moon’s surface. With this, the Indian spacecraft has now completed all the required Moon-bound manoeuvres, paving the way for the upcoming separation of the lander module – a composition of the lander and rover – from the propulsion module.

After separation, the lander will undergo a “deboost” to position itself in an orbit with a closest point (Perilune) of 30km and a farthest point (Apolune) of 100km. This orbit sets the stage for the planned soft landing attempt on the lunar south pole on August 23 at 5:47 pm.

India and Russia’s Lunar race:

Luna-25’s launch on August 11 was facilitated by a robust Soyuz-2 Fregat booster, while ISRO selected the Launch Vehicle Mark-III for the Chandrayaan-3 mission launched on July 14.

Notably, Luna-25 benefits from excess fuel storage, eliminating concerns about fuel efficiency. This advantage allows Luna-25 to pursue a more direct trajectory, Dr K Sivan, former ISRO chairperson told to PTI. In contrast, Chandrayaan-3’s limited fuel-carrying capacity necessitated a more circuitous route to reach the Moon.

Furthermore, Luna-25 boasts a leaner lift-off mass of 1,750 kilograms, significantly lighter than Chandrayaan-3’s 3,800 kilograms. This reduced mass empowers Luna-25 to achieve acceleration more efficiently.