Mission Luna: Russia's Lunar Journey Through Triumphs and Tragedy

 “The apparatus moved into an unpredictable orbit and ceased to exist as a result of a collision with the surface of the Moon," Roscosmos said in a statement. Russia's first moon lander in 47 years has crashed into the lunar surface, the country's space agency reported on 20 august 2023.

The failure underscored the decline of Russia's space power since the glory days of Cold War competition when Moscow was the first to launch a satellite to orbit the Earth - Sputnik 1, in 1957 - and Soviet cosmonaut Yuri Gagarin became the first man to travel into space in 1961.

Russia’s last expedition to the moon was Luna 24 in 1976. The Luna 24 probe was the third Soviet mission to retrieve lunar ground samples. Luna-25 was launched on Aug. 10 and it reached lunar orbit six days later. It was supposed to touch down near the moon's south pole, perhaps as early as 21 August 2023.

 Launch was on a Soyuz-2 Fregat into Earth orbit. It then fired the Fregat upper stage again to go into a lunar transfer orbit. (Soyuz-2 is a modernized version of the Soviet Soyuz rocket. In its basic form, it is a three-stage launch vehicle for placing payloads into low Earth orbit.)  On 16 August it reached the Moon and fired its engines to enter lunar orbit. On August 19 at 11:10 UT it fired its engines to go into its pre-landing orbit, but at 11:57 UT communications were lost. It reportedly has crashed on the lunar surface.

 Landing would have been in the region of the lunar south pole, the main landing site was at 69.545 S, 43.544 E, north of Boguslavsky crater (Boguslavsky is a lunar impact crater that is located near the southern lunar limb). The lander was expected to operate on the lunar surface, studying surface regolith and exospheric dust and particles, for one year.

 Two primary scientific objectives of the mission were: To study composition of the polar regolith (The layer of unconsolidated solid material covering the bedrock of a planet), and to study the plasma and dust components of the lunar polar exosphere.

Brief about the lander:

The lander had a four-legged base containing the landing rockets and propellant tanks, an upper compartment holding the solar panels, communication equipment, on-board computers, radio thermal heaters and radiators, and most of the science apparatus.

The lander had a 1.6-meter-long Lunar Robotic Arm (LRA, or Lunar Manipulator Complex) to remove and collect the surface regolith to depths of 20 to 30 cm. The LRA was equipped with a scoop and a sample acquisition tool.

There were eight important instruments.

ADRON-LR: a gamma-ray and neutron spectrometer to study the surface regolith.

ARIES-L:  To detect charged particles and neutrals in the polar exosphere.

LIS-TV-RPM: An infra-red spectrometer, to measure the surface water content and OH and was mounted on the LRA.

LASMA-LR: Mass spectrometer to measure composition of regolith samples (1 - 2 cubic cm) from the LRA using laser ablation (Laser ablation or photoablation (also called laser blasting) is the process of removing material from a solid (or occasionally liquid) surface by irradiating it with a laser beam).

PML detector:   To study dust in the polar exosphere.

STS-L: A panoramic and local imaging system.

THERMO-L: To study the regolith thermal properties, the lander was also carrying a Laser retroreflector panel.

 

 Tragically on 21 August, a preliminary analysis of the lunar mission suggested that a deviation between the actual and calculated parameters of the propulsion maneuver led to the spacecraft transitioning into an unintended orbit, resulting in its collision with the lunar surface and subsequent loss. A special commission has begun looking into the exact causes of the incident