ISRO’s third Moon mission Chandrayaan-3’s Lander Module (LM) is all set to land on the lunar surface on Wednesday evening, as India eyes becoming the first country to reach the uncharted south pole of Earth’s only natural satellite.
The LM comprising the lander (Vikram) and the rover (Pragyan), is schedule to make a soft landing near the south polar region of the Moon at 6:04 pm on 23rd August 2023.
If the Chandrayaan-3 mission succeeds in making a touchdown on the moon and in landing a robotic lunar rover in ISRO’s second attempt in four years, India will become the fourth country to master the technology of soft-landing on the lunar surface after the US, China and Soviet Union.
Chandrayaan-3 is a follow-on mission to Chandrayaan-2 and its objectives are to demonstrate safe and soft-landing on the lunar surface, roving on the Moon, and to conduct in-situ scientific experiments.
Chandrayaan-2 had fail in its lunar phase when its lander ‘Vikram’ crash into the surface of the Moon following anomalies in the braking system in the lander while attempting a touchdown on 7th September, 2019. Chandrayaan’s maiden mission was in 2008.
The Rs 600 crore Chandrayaan-3 mission was launch on 14th July 2023 onboard Launch Vehicle Mark-III (LVM-3) rocket, for a 41-day voyage to reach near the lunar south pole.
The soft-landing is being attempt days after Russia’s Luna-25 spacecraft crash into the Moon after spinning out of control.
Race for Moon Resources Has Begun, Says Russia's Space Chief After Luna-25 Crash
— 2YoDoINDIA News Network (@2yodoindia) August 22, 2023
for more news visit https://t.co/98KV4yIruC#2YoDoINDIA #Luna25 #Luna25Crash #Russia #Roskosmos #RussiaSpaceAgency #NASA pic.twitter.com/ypSD42znGw
After the second and final deboosting operation on 20th August 2023, the LM is place in a 25 km x 134 km orbit around the Moon.
The module would undergo internal checks and await the sun-rise at the designated landing site, ISRO has said, adding that the powered descent, to achieve a soft landing on the Moon’s surface is expect to be initiate at around 5:45 pm on 23rd August, 2023.
The critical process of soft-landing has been dub by many including ISRO officials as “17 minutes of terror“, with the entire process being autonomous when the lander has to fire its engines at the right times and altitudes, use the right amount of fuel, and scan of the lunar surface for any obstacles or hills or craters before finally touching down.
After checking all the parameters and deciding to land, ISRO will upload all the require commands from its Indian Deep Space Network (IDSN) at Byalalu near here, to the LM, a couple of hours before the scheduled time touchdown.
According to ISRO officials, for landing, at around 30 km altitude, the lander enters the power braking phase and begins to use its four thruster engines by “retro firing” them to reach the surface of the moon, by gradually reducing the speed.
This is to ensure the lander doesn’t crash, as the Moon’s gravity will also be in play.
As on reaching an altitude of around 6.8 km, only two engines will be use, shutting down the other two, aim at giving the reverse thrust to the lander as it descends further, they said, then, on reaching an altitude of about 150-100 metres, the lander using its sensors and cameras, would scan the surface to check whether there are any obstacles and then start descending to make a soft-landing.
ISRO Chairman S Somanath had recently said the most critical part of the landing will be the process of reducing the velocity of the lander from 30km height to the final landing, and the ability to reorient the spacecraft from horizontal to vertical direction.
S Somanath said :
“This is the trick we have to play here,”.
“The velocity at the starting of the landing process is almost 1.68 km per second, but (at) this speed (the lander) is horizontal to the surface of the Moon. The Chandrayaan-3 here is tilted almost 90 degrees, it has to become vertical. So, this whole process of turning from horizontal to vertical is a very interesting calculation mathematically. We have done a lot of simulations. It is here where we had the problem last time (Chandrayaan-2),”.
After the soft landing, the rover will descend from the lander’s belly, onto the Moon’s surface, using one of its side panels, which will act as a ramp.
The lander and rover will have a mission life of one lunar day (about 14 earth days) to study the surroundings there.
ISRO officials do not rule out the possibility of them coming to life for another lunar day.
The lander will have the capability to soft-land at a specified lunar site and deploy the rover which will carry out in-situ chemical analysis of the lunar surface during the course of its mobility.
The lander and the rover have scientific payloads to carry out experiments on the lunar surface.
S Somanath said :
“After powered descent onto the landing site, there will be deployment of ramp and rover coming out. After this, all the experiments will take place one after the other, all of which have to be completed in just one day on the moon, which is 14 days,”.
Stating that as long as the sun shines all the systems will have their power, S Somanath said :
“The moment the sun sets, everything will be in pitch darkness, the temperature will go as down as low as minus 180-degree Celsius; so it is not possible for the systems to survive, and if it survives further, then we should be happy that once again it has come to life and we will be able to work on the system once again, and we hope like that to happen.”
Polar regions of the moon are very different terrain due to the environment and the difficulties they present and therefore have remain unexplore.
All the previous spacecraft to have reach the Moon landed in the equatorial region, a few degrees latitude north or south of the lunar equator.
The Moon’s south pole region is also being explore because there could be a possibility of the presence of water in permanently shadowed areas around it.
The LM has payloads including RAMBHA-LP which is to measure the near-surface plasma ions and electrons density and its changes, ChaSTE Chandra’s Surface Thermo Physical Experiment to carry out the measurements of thermal properties of the lunar surface near-polar region and ILSA (Instrument for Lunar Seismic Activity) to measure seismicity around the landing site and delineating the structure of the lunar crust and mantle.
The rover, after the soft-landing, would ramp down the lander module and study the surface of the moon through its payload APXS – Alpha Particle X-Ray Spectrometer to derive the chemical composition and infer mineralogical composition to further enhance understanding of the lunar surface.
The rover also has another payload Laser Induce Breakdown Spectroscope (LIBS) to determine the elemental composition of lunar soil and rocks around the lunar landing site.
Ahead of its schedule landing on the moon, Chandrayaan-3’s LM has establish two-way communication with Chandrayaan-2’s orbiter which continues to orbit around the Moon.
The two-way contact potentially offers ground controllers (MOX-Mission Operations Complex in Bengaluru) more channels for communication with Chandrayaan-3.
The Chandrayaan-2 spacecraft comprising an orbiter, lander and rover was launch in 2019.
Lander with a rover inside crash into the moon’s surface, failing in its mission to achieve a soft landing.
The ISRO had said that due to the precise launch and orbital manoeuvres, the mission life of the Chandrayaan-2 orbiter, which had separate from the lander and rover, is increase to 7 years.
S Somanath has said instead of a success-based design in Chandrayaan-2, the space agency opted for a failure-based design in Chandrayaan-3, focused on what can fail and how to protect it and ensure a successful landing.
S Somanath said :
“We looked at very many failures – sensor failure, engine failure, algorithm failure, calculation failure. So, whatever the failure we want it to land at the required speed and rate. So, there are different failure scenarios calculated and programmed inside.”
The LM of Chandrayaan-3 successfully separate from the Propulsion Module on 17th August 2023, which was 35 days after the satellite was launch on 14th July 2023.
While, the Propulsion Module, whose main function was to carry the Lander Module from launch vehicle injection to lander separation orbit, will continue its journey in the current orbit for months/years, ISRO said.
Apart from this, the Propulsion Module also has one scientific payload as a value addition.
The SHAPE (Spectro-polarimetry of Habitable Planet Earth) payload onboard it, whose future discoveries of smaller planets in reflect light would allow us to probe into a variety of Exo-planets which would qualify for habitability (or for the presence of life).
Chandrayaan-3 enter into the lunar orbit on 5th August 2023, following which orbit reduction manoeuvres were carried out on the satellite on 6th, 9th, 14th and 16th August 2023, ahead of the separation of both its modules on 16th August 2023, in the run-up to the landing on 23rd August 2023.
Earlier, over five moves in the three weeks since the 14th July 2023 launch, ISRO had lift the Chandrayaan-3 spacecraft into orbits farther and farther away from the Earth.
Then, on 1st August 2023 in a key manoeuvre, a slingshot move, the spacecraft was sent successfully towards the Moon from Earth’s orbit.
Following this trans-lunar injection, the Chandrayaan-3 spacecraft escape from orbiting the Earth and began following a path that would take it to the vicinity of the moon.
Chandrayaan-3 Landing Could Be Shifted to 27th August 2023 if Factors Unfavourable on 23rd August 2023 : ISRO Scientist
If any factor regarding the lander module appears unfavourable, then the landing will be shift to 27th August 2023, said the Space Applications Centre-ISRO about Chandrayaan-3 on 21st August, 2023.
Nilesh M Desai, director of Space Applications Centre-ISRO, Ahmedabad said that the decision regarding the landing will be taken based on the health of the lander module and the conditions on the Moon.
Nilesh M Desai said :
“On 23rd August 2023, two hours before Chandrayaan-3 lands on the Moon, we will decide on whether or not it will be appropriate to land it at that time based on the health of the lander module and the conditions on the Moon. In case, if any factor appears to be not favourable, then we will land the module on the Moon on 27th August 2023. No problem should occur and we will be able to land the module on 23rd August 2023,”.
ISRO Chairman and Secretary Department of Space S Somanath called on the Union Minister of State (Independent Charge) Science and Technology, Atomic Energy and Space Jitendra Singh in New Delhi and apprise him of the status and readiness of ‘Chandrayaan-3′ for the moon landing scheduled on 23rd August, 2023.
Chairman ISRO briefed the minister on the health status of Chandrayaan-3 and said that all systems are working perfectly and no contingencies are anticipate on 23rd August, 2023.
In the next two days, the health of Chandrayaan-3 will be continuously monitor.
The final sequence of landing will be load two days ahead and tested out, S Somanath said.
During the meeting, Minister Jitendra Singh express his confidence in ‘Chandrayaan-3′ making a soft landing this time and hoped that it will script a new history of planetary exploration under the guidance of Prime Minister Narendra Modi.
ISRO said the Chandrayaan-3 is set to land on the moon on 23rd August, 2023, around 18:04 hours IST.
Live actions will be available on the 2YoDoINDIA website, its YouTube channel, Facebook, and 2YoDo TV Facebook page from 17:25 IST on 23rd August, 2023.
2YoDo Invites You to Join LIVE on Chandrayaan-3 Mission Soft-landing on 23rd Aug, 2023 at 5:25 PM.
— 2YoDoINDIA News Network (@2yodoindia) August 22, 2023
Details : https://t.co/bwAVlIg7Nv
LIVE on 2YoDo's : YouTube | Facebook | 2YoDo TV | Website#2YoDoINDIA #Chandrayaan3 #SoftLanding #ISRO #ISROMissionForMoon #Moon #LiveOn2YoDo pic.twitter.com/tH7bRxElgT
While the Chandrayaan-2 mission was only “partially successful” since the lander lost contact after a hard landing, the ISRO successfully establish two-way communication between the Chandrayaan-3 lander module and the still-orbiting Chandrayaan-2 orbiter.
In a significant development, the Chandrayaan-2 orbiter which was already fix around the moon establish a two-way connection with the lander module of Chandrayaan-3 on 21st August, 2023.
As the ISRO share new images of the lunar far side area capture by the Chandrayaan-3.
ISRO Releases Images of Lunar Far Side Area Captured by Chandrayaan-3's Lander Camera
— 2YoDoINDIA News Network (@2yodoindia) August 21, 2023
for more news visit https://t.co/98KV4yIruC#2YoDoINDIA #ISRO #Chandrayaan3 #Moon pic.twitter.com/mkqMS62Jlw
India will be the fourth country in the world to achieve this feat after the United States, Russia, and China, but India will be the only country in the world to land on the lunar south pole.
The primary objectives of the Chandrayaan-3 mission are threefold to demonstrate safe and soft landing on lunar surface; to demonstrate rover roving on the moon, and to conduct in-situ scientific experiments.
Jitendra Singh recall that the first in the series of Chandrayaan or Chandrayaan-1, is credit for having discover the presence of water on the surface of the Moon, which was a new revelation for the world and even the premier Space agencies like the USA’s NASA were fascinate by this discovery and use the inputs for their further experiments.
S Somanath said that corrective measures have been taken after going through data generated by the Chandrayaan-2 mission.
When asked if those additional systems too were indigenous, K Sivan said, “Everything is indigenous.”
The Chandrayaan-3 mission’s lander is name after Vikram Sarabhai (1919–1971), who is regard as the father of the Indian space program.
Why Are Space Agencies Racing to the Lunar South Pole?
India’s space agency is attempting to land a spacecraft on the moon’s south pole, a mission that could advance India’s space ambitions and expand knowledge of lunar water ice, potentially one of the moon’s most valuable resources.
Here’s what’s known about the presence of frozen water on the moon and why space agencies and private companies see it as a key to a moon colony, lunar mining and potential missions to Mars.
Water on the Moon
As early as the 1960s, before the first Apollo landing, scientists had speculate that water could exist on the moon.
Samples the Apollo crews return for analysis in the late 1960s and early 1970s appeare to be dry.
In 2008, Brown University researchers revisit those lunar samples with new technology and found hydrogen inside tiny beads of volcanic glass.
In 2009, a NASA instrument aboard the Indian Space Research Organisation’s Chandrayaan-1 probe detect water on the moon’s surface.
Another NASA probe that hit the south pole found water ice below the moon’s surface.
An earlier NASA mission, the 1998 Lunar Prospector, had found evidence that the highest concentration of water ice was in the south pole’s shadow craters.
Why is Water on Moon Important?
Scientists are interest in pockets of ancient water ice because they could provide a record of lunar volcanoes, material that comets and asteroids delivered to Earth, and the origin of oceans.
If water ice exists in sufficient quantities, it could be a source of drinking water for moon exploration and could help cool equipment.
It could also be broken down to produce hydrogen for fuel and oxygen to breathe, supporting missions to Mars or lunar mining.
The 1967 United Nations Outer Space Treaty prohibits any nation from claiming ownership of the moon.
There is no provision that would stop commercial operations.
A US-led effort to establish a set of principles for moon exploration and the use of its resources, the Artemis Accords, has 27 signatories.
China and Russia have not sign.
Tricky South Pole
Attempt landings on the moon have fail before.
Russia’s Luna-25 craft had been schedule to land on the south pole this week but spun out of control on approach and crashed.
The south pole, far from the equatorial region target by previous missions, including the crewed Apollo landings is full of craters and deep trenches.
ISRO’s Chandrayaan-3 mission is on track for an attempt landing on 23rd August 2023, the space agency has said.
A previous Indian mission fail in 2019 to safely land near the area target by Chandrayaan-3.
Both the United States and China have plan missions to the south pole.
