The Moon rover, Chandrayaan-3, which recently completed its 14-day mission, made history by landing on the lunar south pole. Dr Laura McKemmish, an astrochemist from UNSW Sydney, explains the significance of the mission and what the future holds for lunar exploration.

"This is the first landing of India on the Moon, and it will make India the fourth country ever to land on the Moon," says Dr McKemmish. "The ability of our global civilisation to go into space exploration is really, really crucial to enable humankind as a global community to explore elsewhere in the universe."

Interest in the southern pole of the Moon stems primarily from the fact that scientists have been aware of the presence of frozen water there, and locating water is a large part of Chandrayaan-3's mission. "Identifying frozen bodies of water on the Moon is a really important gateway for further space discovery in our solar system."

Navigating craters, darkness and extreme temperatures
Following a failed mission to land on the Moon in 2019, India joined the US, China and the Soviet Union as only the fourth country to reach this milestone.

Chandrayaan means "moon vehicle" in Hindi and Sanskrit. The vehicle took off from a launch pad in southern India on July 14 and completed a 'soft landing' on the Moon nine days later. A soft landing is when the space shuttle is kept intact.

Attempts by various space agencies have been made to land on the south pole of the Moon, but it's notoriously difficult to do, thanks to rugged terrain, extreme temperatures, lack of light and communication difficulties.

"Humans have been landing on the equator of the Moon for more than half a century," says Dr McKemmish. "And while a soft landing is always more technical, when the landscape is more cratered, such as it is at the south pole, that landing becomes even harder. There's also increased complexities with communication at the poles, compared to the equator."

Chandrayaan-3 will be running a series of experiments including a spectrometer analysis of the mineral composition of the lunar surface.

"Generally a moon rover will be digging up samples, taking lots of photos, and taking various spectral readings investigating how the material interacts with light," says Dr McKemmish.

"For this mission, the spectroscopic technique used is basically focusing a laser on the surface, causing the Moon rocks to become a plasma. This plasma emits colours of light depending on its composition and thus this measurement tells us a lot about the geology and history of the rock."

Already, this technique has been used to measure the presence of aluminum, silicon, calcium, iron and sulphur on the surface of the Moon, as confirmed by ISRO.

Since the Moon rover has completed its walk, scientists will be analysing data looking for signs of frozen water.

Using water to make rocket fuel
Water ice has already been definitively confirmed at the poles of the Moon.

"If you think of most of the surface of the Moon, it goes in and out of sunlight, making the temperature range quite large," says Dr McKemmish. But the water at the poles has been detected in the shadows of craters, where the temperatures never reach above -250 degrees Fahrenheit, and due to the minimal tilt of the Moon's rotation axis, sunlight never reaches these regions.

Initially, scientists from the University of Hawaii, Brown University and NASA used data from an instrument that was on board the Chandrayaan-1 spacecraft, launched in 2008 by the ISRO, that was uniquely equipped to confirm the presence of solid ice on the Moon, without landing on it.

"Scientists first looked for water by studying the surface, as it reflects light in a different way to other geology. This was corroborated when they shone infrared light down. That's light that emits at a lower energy than our visible light, and water absorbs it at a characteristic frequency."

Water not only supports life, and could be used by astronauts stationed permanently on the Moon - but it also has other important uses.

"Water can be broken down into hydrogen and oxygen," says Dr McKemmish. "As well as allowing us to breathe, oxygen has some other essential ways in which it can support humans. In particular, oxygen and hydrogen together are a fuel that can power spacecraft built from material on the Moon to missions to other parts of the Solar System."

Use of Moon-based material and fuel is significant because getting anything from Earth's gravitational pull up into space is really expensive, as it requires a huge amount of energy.

"Anything that you can create or find on somewhere like the Moon, which has much lower gravity, means it's much cheaper and this could make it far easier to pursue a human mission to Mars.

"This work is building towards a permanent base on the Moon, like how there is permanent human presence on the International Space Station. It's about moving towards constructing spacecraft in orbit, because it's a lot cheaper if we can do things in space."

Lessons from Chandrayaan-3
While this mission has been a historic moment in itself, it has also acted as a gateway to further discovery.

As Dr McKemmish explains, exploring the south pole of the Moon is exploring a new region of the planetary surface. "If you think about Earth, Antarctica is completely different than the middle of the Australian desert, which is completely different from the Amazon rainforest.

"And obviously, life creates some of this variation. But even without life, there's a lot of variability on earth, and that tells us a lot of interesting things about the history."

Dr McKemmish emphasises that the surface of the Moon is not all homogenous. "It is fascinating scientifically to understand the diversity of the Moon's different environments, but it is also important economically. Beyond the crucial presence of water in the south pole regions, we are really interested in knowing if there are regions near these water deposits that are particularly metal rich. This would be a perfect location for a future Moon base."

Importantly, it's also telling a story where space isn't dominated by a few countries, but invites a more global community into exploring space. Since the Chandrayaan-3 spacecraft mission, the ISRO has already launched a rocket to study weather patterns from the sun.

"Australia is a reasonably small country worldwide, and we thought it was important enough to create a space agency," says Dr McKemmish. "In fact, the Australian Space Agency is launching a Moon rover on the Artemis mission as soon as 2026. And you can even take a crack at naming the spaceship!"

Quelle: SD

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Update: 20.09.2023

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Chandrayaan-3: How important are India's Moon mission findings?

A photo of the Vikram lander taken by Pragyaan rover

Isro has provided regular updates on their movements and findings and shared images taken by them.

These updates have excited many Indians, but others have been asking about the significance of these discoveries.

The BBC asked Mila Mitra, a former Nasa scientist and co-founder of Stem and Space, a Delhi-based space education company, to pick some of Chandrayaan-3's major findings and explain their significance.

The distance covered - and craters avoided

Hours before the rover was put to bed on 2 September, Isro said Pragyaan "has traversed over 100m [328 feet] and is continuing".

That's quite a long way to travel for the six-wheeled rover, which moves at a speed of 1cm per second.

What is also significant, Ms Mitra says, is that it has been able to stay safe and avoid falling into the craters that dot the Moon's little-explored south pole region.

The rover, she says, has a special wheel mechanism - called rocker bogie - which means that all its wheels don't move together, helping it traverse up and down, but it may not be able to climb out if it falls into a deep crater. So it's important to make it go around the craters or even retrace its steps. And that, Ms Mitra adds, is done by scientists at the command centre who are "watching the Moon through the rover's eyes".

"The rover is not automated and its movements are controlled from the command centre which acts on the basis of the pictures it sends.

"There's a slight delay before they reach the command centre because of the circuitous route they take - Pragyaan sends them over to the lander which sends them on to the orbiter to pass them on to Earth."

Isro released a graphic of the path taken by the lunar rover

So, by the time the command reaches the rover, it's a few steps closer to the threat.

But the fact that it has managed to navigate safely around two craters shows that it's able to communicate really quickly with the command centre, Ms Mitra adds.

Blowing hot and cold

The first set of data collected from the lunar topsoil and up to the depth of 10cm (4 inches) below the surface from a probe onboard the Vikram lander showed a sharp difference in temperatures just above and below the surface.

While the temperature on the surface was nearly 60C, it plummeted sharply below the surface, dropping to -10C at 80mm (around 3 inches) below the ground.

The Moon is known for extreme temperatures - according to Nasa, daytime temperatures near the lunar equator reach a boiling 120C (250F), while night temperatures can plunge to -130C (-208F). And temperatures of -250C (-410F) have been recorded at craters which never receive any sunshine and remain permanently in shadows.

But, Ms Mitra says, this wide variation in temperature is significant because it shows that Moon's soil - called lunar regolith - is a very good insulator.

 

"This could mean it could be used to build space colonies to keep heat and cold and radiation out. This would make it a natural insulator for habitat," she says.

It could also be an indicator of the presence of water ice below the surface.

A clue into the Moon's evolution

When a laser detector mounted on the rover measured the chemicals present on the lunar surface near the south pole, it found a host of chemicals such as aluminium, calcium, iron, chromium, titanium, manganese, silicon and oxygen.

But the most important of the findings, scientists say, relate to sulphur. The instrument's "first-ever in-situ - in the original space" measurement "unambiguously confirms" the presence of sulphur, Isro said.

Sulphur's presence on the Moon has been known from the 1970s, but scientists say the fact that the rover has measured sulphur on the lunar surface itself - and not inside a mineral or as part of a crystal - makes it "a tremendous accomplishment".

Ms Mitra says the presence of sulphur in the soil is significant on a number of counts.

"Sulphur comes usually from volcanoes so this will add to our knowledge of how the Moon was formed, how it evolved and its geography.

"It also indicates the presence of water ice on the lunar surface and since sulphur is a good fertiliser, it's good news as it can help grow plants if there's habitat on the Moon."

Was it really a Moonquake?

The Vikram lander carries an instrument that measures vibrations emanating from its own studies and experiments as well as those from the rover and its activities.

Isro said while the Instrument for Lunar Seismic Activity (Ilsa) had its ear to the ground, it also recorded "an event, appearing to be a natural one" and was investigating its source.

IMAGE SOURCE, ISRO

This event had much larger amplitude which means it was much stronger, Ms Mitra says, adding that there could be several explanations for this.

"It could be some space debris - such as a meteorite or an asteroid - hitting the surface. Or it could be seismic which would make it the first Moonquake recorded since the 1970s. In that case, this could lead to an explanation of what's under the Moon's surface and its geography."

What's lunar plasma?

When Isro posted on X (formerly Twitter) that a probe on the lander had done the "first-ever measurements of the near-surface lunar plasma environment" of the south polar region and found it to be "relatively sparse", many wondered what it meant.

Ms Mitra explains that plasma refers to the presence of charged particles in the atmosphere which could hinder the radio-wave communication that Chandrayaan-3 is using.

"The fact that it's very sparse or thin is good news as it means it will disrupt the radio communication a lot less."

When the lander hopped

The last thing the Vikram lander did before being put to bed in early September was what Isro called a "hop experiment".

The agency said the lander was "commanded to fire its engines, it rose up by about 40cm [16 inches] and landed at a distance of 30-40cm".

This "successful experiment" means the spacecraft could be used in future to bring samples back to the Earth or for human missions, it added.

Now, could this short hop mean a giant leap for India's future space plans?

Ms Mitra says the "hop tested restarting the engine after a lunar landing to make sure it is still operating fine".

It also demonstrated that the craft has the "capacity for lift-off in a lunar soil environment since so far the testing and real lift-off has only been from Earth", she adds.

Quelle: BBC

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Update: 22.09.2023

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“Almost like taking out something from freezer,” Ex-ISRO chief on ‘waking up’ Chandryaan-3’s Vikram, Pragyan

As Indian Space Research Organisation (ISRO) preps to revive Chandrayaan-3’s Vikram lander and rover from ‘sleep mode’ after almost two weeks, former ISRO chairman Madhavan Nair on Friday said there is a fairly good chance that the system will be operational again.

Ahead of the second phase of the lunar mission of Chandryaan-3, former Indian Space Research Organisation (ISRO) Chairman Madhavan Nair has said that there is a fairly good chance that the system will be operational again despite the extremely cold temperature on the moon's surface. "Vikram Lander and Pragyan Rover have been in deep sleep for almost two weeks now. It is almost like taking out something from the freezer and then trying to use it. The temperatures would have gone beyond -150 degrees Celsius," Nair told ANI.

ISRO is gearing up to wake the Vikram lander and Pragyan from the 'sleep mode' to face the sun's rays after they were put into after having completed their set tasks. The Vikram lander of the Chandrayaan-3 mission had touched down near the south pole of the moon on August 23 in a historic landing. The former ISRO chairman said there is a fairly good chance that the system will be operational again.

"At that temperature how the batteries, the electronics and the mechanism survived is really a concern. Of course, adequate tests have been done on the ground to establish that it will work even after such conditions. But still, we have to keep our fingers crossed," the ex-ISRO chief said. He further said, "The solar heat will warm up the instruments and also recharge the batteries. If both these conditions are successfully met, there is a fairly good chance that the system will be operational again."

He also asserted that if the lander and rover activate successfully then it will help to collect more data from the lunar surface. "Once it comes to operation it is quite possible that we can move around for some distance over the next 14 days and collect adequate data, more data on the surface conditions on the Moon near the South Pole," Nair said.

Meanwhile, former ISRO scientist Tapan Mishra said that even if the rover fails to revive and the lander works, it will be a miracle. "Originally the Chandrayaan lander rover was designed for only 14 days of operation. It is expected that the temperature will go down to -140 degrees Celsius or lower, in the Southern pole it can reach down to -200 degrees Celsius. At this temperature, no plastic material, no carbon power material or no electronics can survive. They will crack. But I'm hopeful that ISRO must have done a lot of thermal management thing," Mishra told ANI in Kolkata.

He further said, "If they are successful in the thermal management, if ISRO's design becomes successful, then tomorrow when the lunar daytime starts then all payloads in the lander and the rover may start working. Even if the rover doesn't work and the lander works, it will really be a miracle." Mishra asserted that if it survives one night then it will survive many more lunar nights.

"And if it happens, then we will be in a league that can operate the lunar lander, rover, even throughout the year. If it survives one lunar night, I'm sure it will survive many more lunar nights and it may probably operate from 6 months to one year. That will be a great thing," he said. Mishra added, "I'm hoping against hope that though ISRO has already satisfied the lander rover could work for 13-14 days when tomorrow when it wakes up then it will be a great credit to ISRO scientists and also if it wakes up tomorrow then it will wake up again the next lunar night and probably it will last much longer. It will give much more valuable information."

He also said that confirming the presence of water is the next important thing. "There was a lesser induced spectroscopy instrument. It has shown us all the expected metals there. It has also shown us the presence of oxygen there, but we are looking for water. The oxygen can come from the breaking of any other silicon material which is actually the basis of all the rocks anywhere in the universe, also it can come from the breaking up of water.

"But if we could detect hydrogen there, detecting the presence of hydrogen would conclusively prove that there is water because hydrogen is never part of any other compound. So in that case we will be able to conclusively prove that there is water there. We have remote sensing-wise shown the presence of water. Now physically also we will able to show," he added. After having landed, the Vikram lander and the Pragyan rover performed different sets of tasks on the lunar surface for about 14 days, including finding the presence of sulphur and other minor elements, recording relative temperature, and listening to movements around it. One day on the Moon is equal to 14 days on Earth.

The stated objectives of Chandrayaan-3, India's third lunar mission were a safe and soft landing, rover roving on the Moon's surface, and in-situ scientific experiments. In early September, the Vikram lander and Pragyan rover were set in "sleep mode". (ANI)

(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)

Quelle: Devdiscourse

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Update: 24.09.2023

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ISRO Attempts to Revive Communication With Vikram Lander, Pragyan Rover

The primary challenge for 'Pragyan and Vikram' lies in reactivating after enduring the extreme -200 degrees Celsius temperatures.

New Delhi: The Indian Space Research Organisation (ISRO) on Friday, September 22 said it has made efforts to establish communication with its lunar mission Chandrayaan-3’s lander Vikram and rover Pragyan to ascertain their ‘wake-up condition’ after they had been put into sleep mode early this month. However, as of now, no signals have been received from them, PTI reported.

The primary challenge for ‘Pragyan and Vikram’ lies in reactivating after enduring the extreme -200 degrees Celsius temperatures.

If the onboard instruments withstand the low temperatures on the Moon, the modules can reactivate and resume their mission ofsending information from the moon for the next 14 days.

“Efforts have been made to establish communication with the Vikram lander and Pragyan rover to ascertain their wake-up condition. As of now, no signals have been received from them. Efforts to establish contact will continue.” ISRO said in a post on ‘X’.

“We have put both the lander and rover on sleep mode because temperature would go as low as minus 120-200 degree Celsius. From September 20 onwards, sunrise will be going on at the Moon and by September 22 we hope that the solar panel and other things will be fully charged, so we will be trying to revive both the lander and rover, ” ISRO’s Space Applications Centre director, Nilesh Desai, had told PTI on Thursday.

Quelle: WIRE

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Update: 26.09.2023

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ISRO To Wait For 14 More Days In Bid To Reestablish Contact With Chandrayaan-3

Since their touchdown on the uncharted lunar southern polar region on August 23, after a 40-day interstellar journey, ISRO has been unable to make contact with the Vikram lander and Pragyan rover despite persistent efforts.

Chandrayaan-3s Rover Pragyan on south pole of lunar surface

The Indian Space Research Organization (ISRO) is extending its patience by another 14 days in its quest to establish communication with Chandrayaan-3's Vikram lander and Pragyan rover. As they continue their attempts to revive these lunar explorers, the clock is ticking until the next lunar sunset, which is scheduled for October 6.

Since their touchdown on the uncharted lunar southern polar region on August 23, after a 40-day interstellar journey, ISRO has been unable to make contact with the Vikram lander and Pragyan rover despite persistent efforts. On September 2, the duo was placed in sleep mode following the successful completion of their initial tasks.

Prior to the communication blackout, the Pragyan rover had ventured more than 100 meters across the lunar surface, confirming the presence of elements such as sulphur, iron, oxygen, and others on the moon. However, hopes of revival have yet to materialize.

ISRO's determination remains unwavering as they persist in their efforts to establish contact with the lander and rover until the next lunar sunset, set for September 30. The agency continues to hold out hope that the sunrise on Shivshakti Point, their current location, may reawaken the equipment. Nonetheless, the timeline for re-establishing contact with the Chandrayaan-3 instruments remains uncertain.

ISRO confirmed, "We will continue to ping it. But as of now, there has been no communication." The slim chances of revival were always anticipated due to the harsh lunar conditions during the extended lunar night. Nilesh M Desai, Director of the Space Applications Centre (SAC), had previously explained that the signal was expected to come automatically as the solar-powered lander and rover recharged following the lunar surface's September 22 sunrise. However, no signals have been received thus far, as reported by India Today.

In the event that the electronics manage to endure the cold temperatures, there remains a 50-50 chance of revival. Should this occur, the lander and rover will resume their scientific experiments on the moon's surface, extending the mission's scientific objectives.

Quelle: Outlook