Modern times

v0.2 - 25-04-2020

Moon landings after the space race

AFter a long gap, the moon is "hot" again with moon landings occurring more frequently. This page is dedicated to those, more recent, moon landings.


Moon Impact Probe

Operator: ISRO

Target:  Moon

Landing date:  November 14th 2008

Status:  Completed


On ISRO's first moon mission, Chandrayaan-1, was a small piggyback lander. This lander, the Moon Impact Probe, was designed to impact the moon sometime after being released from the main vehicle. After separation from the main mission, the probe spun up for stability and fired its retro rocket motor. This caused the orbit of the lander to decrease and thus intersect the surface of the moon. After a 25-minute descent phase the probe "hard landed" with a velocity of 1.69 km/s.

Even though the mission was short it showed ISRO's capabilities of reaching the surface of the moon. Marking India to be the fourth nation to do so. Furthermore, the mission discovered the presence of water just before it hit the ground. This discovery was not made public until the Moon Mineralogy Mapper, a NASA experiment onboard Chandrayaan-1, confirmed this discovery. 


ISRO Moon Impact Probe before launch

Moon Impact Probe before launch

Beresheet 

Operator: Israel Aerospace Industries

Target:  Moon

Landing date:  22-02-2019

Status:  Completed, failed


In 2019 the Israeli company Isreal Aerospace Industries became the first commercial company to land a mission on the moon. The mission was launched onboard a Space X falcon 9 together with the PSN-6 satellite. The lander then used its own engines to fly to the moon where it entered a circular lunar orbit. Just before landing a gyroscope failed which could not be solved due to a sudden loss of communication. When communication was restored the capsule had already impacted the moon. At an altitude of 150, the 150 kg (dry mass) lander was still falling at 140 m/s. A second mission is planned for 2024 including a Moon and Mars lander. 


Chang'e program

Operator: SNSA

Target:  Moon

Landing date:  01-12-2020

Status:  Completed


The Chinese Lunar Exploration Program started with two successful orbital missions launched in 2007 and 2010. The second two missions, Chang'e 3 and 4 showed the Chinese ability to soft-land on the moon. Both landers were about 1200 including a 400 kg rover. Chang'e 3 worked for 959 days, where Chang'e 4 is active today. Before the sample return mission Chang'e 5, there was an intermediate demonstrator called Chang'e 5-T1. This mission was launched in October 2014 to test the re-entry leg of the sample return. The mission became the first successful skipping entry. Chang'e 5 was launched in November 2020, landed in December 2020 and returned to earth on the 16th of that month. The mission marked the first Lunar sample return since Luna 24. The earth entry probe resembled a scaled-down Shenzhou capsule, which in term resembles the Soyuz capsule. 


The follow-up mission, Chang'e 6, is scheduled for 2024 and will repeat the Chang'e 5 mission on the Lunar south pole.


Chandrayaan-2, Vikram lander

Operator: ISRO

Target:  Moon

Landing date:  22-07-2019

Status:  Completed, failed


In 2019 India embarked on the ambitious mission to become the fourth nation to soft-land a lander on the moon. This lander was launched in July 2019 onboard a GSLV Mark-III as part of the Chandrayaan-2 mission. This mission contained an orbital module, lander and rover. After the Chandrayaan-2 mission entered lunar orbit, the lander detached and moved to a lower orbit. Unfortunately, the 1471 kg rover crash crashed due to a computer glitch. During the landing, the velocity was supposed to be changed from 1683 to 146 m/s. However, the capsule flew faster than expected, and thus the landing was hard. Even though the landing was unsuccessful, it impacted close to the predicted landing site. The lander and rover were destroyed upon impact. 


OMOTENASHI

Operator: JAXA

Target:  Moon

Landing date: November 2022

Status:  Completed, failed


OMOTENASHI is one of the CubeSats flying onboard the Artemis 1 mission to the moon. The objective of OMOTENASHI is to demonstrate low-cost landing techniques for the moon. After separation, the satellite will spin up and ignite a small solid rocket motor. The burn will last for about 15 to 20 seconds.  It will then separate the lander from the motor and inflate a 50cm airbag. This airbag ensures a safe landing. The final free-fall is about 100 meters and the final impact will be between 20 and 30 m/s.


After the successful launch in November 2022, the satellite was separated from the Orion spacecraft. Unfortunately, the team on the ground was not able to establish communications with the lander and were thus not able to start the landing sequence. The satellite remains in Lunar orbit. 

Render of the OMOTENASHI lander

Render of the OMOTENASHI lander

Luna 25

Operator: Roscosmos

Target:  Moon

Landing date: August 10th 2023

Status:  Failed


The Luna 25 mission was launched in August 2023 on top of a Soyuz-2.1b rocket. The mission is targeting a lunar landing at the end of August 2023. The mission is the first moon mission of Russia since Luna 24 and the first moon mission flown since the fall of the soviet union. The mission has been in development for quite some time, at least since 2010 when Phobos Grunt was launched. Originally the mission was to include the ESA Pilot-D and the Swiss  LINA-XSAN payload, but these were removed in the wake of the Russian invasion of Ukraine. 


Luna 25 crashed during its landing attempt. From the last updates, it seems that a malfunctioning thruster caused the spacecraft to hit the moon prematurely. The satellite was first placed in a 100km polar orbit and it was intended to be placed in an elliptical orbit with a periapsis of only 18km above the surface of the moon. When the thruster fired too long this orbit started to intersect the moon [187].


Currently, it is unclear how this mission failure impacts the planned Luna 26, 27, and 28 missions.


Luna 25 on the moon

Render of Luna 25 on the moon

Chandrayaan-3

Operator: ISRO

Target:  Moon

Landing date:  2023

Status:  Completed


After the crash of Chandrayaan-2, ISRO officials announced a new moon lander. This lander was to learn from the mistakes of Chandrayaan-2. The main updates included a redesign of the landing engines and the landing software. The software now allowed for attitude corrections in all phases of flight and the control of the attitude was provided by four downwards-facing rockets. 

The lander landed successfully on November 23 2023, after which it deployed a moon rover. This landing makes India the fourth nation to soft land on the moon and the first lander on the lunar south pole. 

Chandrayaan 3 on the moon, photographed by the rover

Chandrayaan 3 on the moon, photographed by the rover

SLIM

Operator: JAXA

Target:  Moon

Landing date:  2023

Status:  Ongoing


Japan has recently launched a new lunar mission that aims to achieve a precise and soft landing on the Moon's surface. The mission, called SLIM (Smart Lander for Investigating Moon), is part of JAXA's (Japan Aerospace Exploration Agency) efforts to advance the exploration of the Moon and other planets using lighter and more efficient systems.

SLIM's landing system consists of four main components: a laser altimeter, a terrain camera, a navigation camera, and a guidance, navigation and control system. These components work together to enable SLIM to perform a pinpoint landing at a specific location within 100 meters, rather than the typical kilometer range.

The laser altimeter is a device that emits laser pulses and measures the time it takes for them to bounce back from the ground. This allows SLIM to determine its altitude and velocity relative to the lunar surface.

The terrain camera is a device that captures images of the landing site and compares them with a pre-loaded map of the area. This allows SLIM to identify its position and orientation on the map, and to avoid any obstacles or hazards.

The navigation camera is a device that tracks landmarks on the lunar surface, such as craters or mountains, and uses them as reference points. This allows SLIM to estimate its location and trajectory, and to correct any errors or deviations.

The guidance, navigation and control system is a software that processes the data from the sensors and computes the optimal commands for the thrusters and attitude control system. This allows SLIM to autonomously adjust its attitude and velocity during the landing phase, and to achieve a soft and accurate landing.

SLIM's scientific objectives are to conduct investigation of the Moon's origins by landing near the Marius Hills Hole, a possible skylight of a subsurface lava tube that could provide clues about the Moon's volcanic history and potential habitability. SLIM will also test technology fundamental to exploration in low-gravity environments, such as wireless power transmission, optical communication, and miniaturized instruments.

JAXA SLIM lander on the moon

Render of JAXA's SLIM lander on the moon

The SLIM lander made its landing in Octoberortionately toppled and did not land with 100% success. The secondary landers however were deployed and provided an image of the lander on the moon. Even though the landing did not completely go as planned the lander still sent back some scientific data.


Hakuto-R

Operator: ISpace

Target:  Moon

Landing date: April 2023 (First flight)

Status:  Operational - in test phase


The Hakuto-R lander has a long history starting in the days of the Google Lunar X Prize to kickstart the moon landers in 2007. Even though the Hakuto lander did not reach a flight-ready state during the competition it managed to fly in November 2022. This launcher included the Rashid rover, the first moon rover of the UAE.


After the launch in 2022, the lander reached the moon. On the 25th of April, the landing attempt was started but ended

with the lander not responding. Currently, the lander is considered lost.


Render of the Hakuto-R lander

Render of the Hakuto-R lander

LUPEX

Operator: ISRO/JAXA

Target:  Moon

Landing date:  2026/28

Status:  Planned


The Lunar Polar Exploration Mission (LUPEX) is a joint venture between the Indian Space Research Organisation (ISRO) and the Japan Aerospace Exploration Agency (JAXA) to explore the south pole region of the Moon for water and other resources. The mission is expected to launch no earlier than 2026 using a Japanese H3 rocket and will consist of an Indian lander and a Japanese rover.

The main objective of LUPEX is to investigate the lunar polar region for the presence and potential usability of water, which could be a valuable resource for future human exploration and settlement of the Moon. The mission will also demonstrate new surface exploration technologies related to vehicular transport and lunar night survival, which are essential for sustainable exploration in the harsh environment of the polar regions.

The lander, developed by ISRO, will carry a payload capacity of 350 kg (770 lb) and will use a feature matching algorithm and navigational equipment derived from JAXA's Smart Lander for Investigating Moon (SLIM) mission for precision landing. The rover, developed by JAXA, will carry multiple instruments by both agencies, including a drill to collect sub-surface samples from 1.5 m (4 ft 11 in) depth.

LUPEX is poised to be a trailblazer in providing concrete answers to the scientific questions about the lunar water resources and their origin, distribution, and evolution. The mission will also pave the way for future collaboration between ISRO and JAXA in lunar exploration and beyond.


Configuration of the LUPEX lander