Chandrayaan-3 mission is expected to send home information about the Moon's atmosphere, soil, minerals etc which may be the first of its kind for the scientific community across the world and of far-reaching implications in the times to come, said Union Minister of State for Space, Dr. Jitendra Singh on Sunday, adding that the Vikram Lander and Pragyan Rover have started performing the Mission objectives exactly as per the schedule.
In an exclusive interview with a media agency, Dr Jitendra Singh said, the main focus of the science payloads onboard Chandrayaan-3 is to provide an integrated assessment of the lunar surface features, including the thermal properties and surface elements of the lunar topsoil (regolith) as well as the plasma environment near the surface, he said. It will also assess the lunar seismic activities and the impact of meteors on the lunar surface.
“All these are essential for the fundamental understanding of the lunar near-surface environment and for making future lunar habitat developments for explorations,” said Dr Jitendra Singh, who is also the Union Minister of State (Independent Charge) Science & Technology; MoS PMO, Personnel, Public Grievances, Pensions, and Atomic Energy.
Vikram Lander carries seismometer (ILSA), ChaSTE, Langmuir Probe (RAMBHA-LP), and a laser retroreflector array payloads and the Pragyan Rover carries Alpha Particle X-ray Spectrometer (APXS) and Laser Induced Breakdown Spectroscope (LIBS) payloads.
“All these payloads are planned for continuous operations from August 24, 2023 till end of the mission,” said Dr Jitendra Singh.
The Instrument for Lunar Seismic Activity (ILSA) will make continuous observations of the lunar seismic activities as well as the meteors impacting the lunar surface. ILSA is the first-ever seismometer sent to study the vibrations on the lunar surface at higher lunar latitudes.
“These measurements will help us plan for future habitat developments by understanding the frequency of potential hazards from meteor impacts and seismic activities,” said Dr Jitendra Singh.
The ChaSTE (Chandra’s Surface Thermo-physical Experiment) is another key instrument mounted on the Vikram Lander, said Dr Jitendra Singh. Ten high-precision Thermal Sensors, mounted on ChaSTE, will dig into the moon’s top soil to study temperature variations. ChaSTE is the first-ever experiment to study the thermophysical properties of the first 10 cm of the lunar surface.
Surface of the moon undergoes substantial temperature variations during the lunar day and night, with minimum temperatures of <-100 ℃ around the local midnight, and >100℃ around the local noon. The porous lunar topsoil (having a thickness of about ~5-20 m) is expected to be an excellent insulator. Because of this insulating property and absence of air, very significant temperature difference is expected between the top surface and interior of the regolith.
“The low density and high thermal insulation of the regolith enhances its potential as a basic building block for future habitats while the assessment of the wide range of temperature variations are crucial for survivability,” said Dr Jitendra Singh.
The study of the near-surface plasma of the Moon and its time variations will be carried out by the Langmuir probe. RAMBHA-LP will be the first-ever in-situ observation of the near-surface plasma and its diurnal variation in higher lunar latitude, where the Sun elevation angle is less, said Dr Jitendra Singh.
“These will help assess the lunar surface charging for future manned missions,” he said.
The Alpha Particle X-ray Spectrometer (APXS) and Laser Induced Breakdown Spectroscopy (LIBS), mounted on the Pragyan, will make the measurements of lunar surface elements at the stop-points (once in about 4.5 hours) along the Rover track. These are first-ever in situ study of lunar surface elemental composition in the higher latitudes, said Dr Jitendra Singh.
“These measurements can make inference on the potential surface elemental compositions which will be helpful for future self-sustaining habitat developments,” he said.
Besides probe instruments mounted on the Lander & Rover, the Chandrayaan-3 Mission carries the Spectropolarimetry of Habitable Planet Earth (SHAPE) onboard the Propulsion orbit of the moon.
“It will help identify earth-like exoplanets in future,” said Dr Jitendra Singh, adding, “The data will be made available to the students and general public after the initial analysis and consolidations.
Though the mission life of Lander and Rover is designed to last one Moon Day, equivalent to 14 Earth days, after which Vikram and Pragyan will go in hibernation, said Dr Jitendra Singh, and after one Moon Night, or 14 Earth Days, ISRO scientists will try their luck if the two would have survived the extremely cold night temperatures and can be revived by residual battery and switching on their solar panels.
Meanwhile, ISRO is gearing up for the launch of Aditya-L1 mission by the first week of September, using the Polar Satellite Launch Vehicle (PSLV) XL with 7 payloads (instruments) onboard. Aditya L1 would be the first space-based Indian mission to study the Sun. The spacecraft shall be placed in a halo orbit around the Lagrange point 1 (L1) of the Sun-Earth system, which is about 1.5 million km from the Earth. A satellite placed in the halo orbit around the L1 point has the major advantage of continuously viewing the Sun without any occultation/eclipses.
Dr Jitendra Singh said the Gaganyaan, India’s first manned mission to space, will be the next major project before ISRO.
“We will have at least two missions before we send a human being. We will have the first mission possibly in September or early next year, where for a few hours we will send an empty spacecraft that will go up and come back into the waters to see if we are able to control its safe return without any damage. If that is successful, then we will have a second trial next year by sending a robot called Vyom Mitra. And if that is also successful, we will send the final mission, which will be the human mission. This could possibly take place in the second half of 2024. Initially we had planned it for 2022, but it got delayed due to Covid,” he said.
Dr Jitendra Singh said that in the past nine years after the Prime Minister Shri Narendra Modi assumed office, been given the freedom to apply space technology to areas of infrastructure development.
“Till the year 2013, 40 launch vehicle missions were accomplished with nearly 3 launches on an average per year. This has doubled in the last 9 years with 53 launch vehicle missions at an average of 6 launches per year,” he said, adding, “ISRO had launched 35 foreign satellites till 2013. This has seen exponential growth in the last 9 years with nearly 400 foreign satellites launched.”
Dr Jitendra Singh said India has established its own regional navigation satellites system serving the strategic and civilian requirements in the last 9 years. PM Modi initiated Space sector reforms, making Space easily accessible for Indian private players and a comprehensive Indian Space Policy 2023 was released covering all stakeholders.
Dr Jitendra Singh said the country started witnessing the emergence of Space sector Startups only after 2014 with nearly 200 startups at present, working across various space domains. The first Indian private sub-orbital launch was witnessed recently which was enabled through the Space sectoral reforms.
“Our ability to reach out to space is now proven beyond doubt as the Prime Minister himself said Space is no limit. So we have gone beyond space to discover the unexplored areas of the universe,” he said.
Dr Jitendra Singh said the ISRO will launch an awareness campaign across the country next month, mobilizing students and the common man in view of the huge interest witnessed in the Live telecast of Chandrayaan-3 Moon Landing.
With over 8 million concurrent viewers, the touchdown of Chandrayaan-3's lander module became the most-watched event on YouTube during live streaming. It even left behind the concurrent viewership of the football match between Brazil and South Korea during the World Cup 2022 quarterfinals, which had garnered 6.1 million views. Around 70 million viewers watched the Chandrayaan-3 landing later. However, the actual number of viewers could be higher due to numerous group screenings.
The awareness campaign will kick off on 1st September and will include online and offline activities including Flashmobs, Mega Town Halls, Quiz contests and Best Selfies, with a focus on Space Startups and Tech Partner Companies.