Missions to study the lunar surface, solar flares, and a joint operation with NASA to observe the Earth — a line-up of India’s space missions this year and next

The year 2023 has been a busy one for the Indian Space Research Organisation (ISRO) with the space agency already successfully completing four missions successfully in the past five months. While this is a milestone in itself, the space calendar for India will continue to remain packed for the coming months, as some of the biggest space missions—including the much-awaited Chandrayaan-3, India’s third lunar mission, Aditya-L1, the sun mission, and the uncrewed and crewed missions of Gaganyaan—are also progressing at a promising pace, scientists assured.

Senior scientists from the department of space said that after the success of the Small Satellite Launch Vehicle (SSLV) D2 or SSLV-D2/EOS-07 mission that was completed in February, the second batch of 36 OneWeb satellites in March, the Polar Satellite Launch Vehicle (PSLV-C55) mission carrying two Singapore satellites, TeLEOS-2 and Lumelite-4, and the launch of India’s first second generation navigation satellite, NavIC or NAVigation with the Indian Constellation, ISRO is now gearing up for India’s third lunar mission, Chandrayaan-3. This will likely be followed by Aditya-L1.

“2023 and 2024 are very exciting years for Indian space missions. We have some heavy-duty missions planned for the year ahead and we are very excited about it. The immediate missions that we are working towards are Chandrayaan-3 and Aditya-L1, India’s moon and sun missions,” a senior ministry official confirmed.

Here’s a closer look at what ISRO’s calendar looks like for the rest of the year and the next.

Chandrayaan-3

ISRO chairman S Somnath confirmed that the launch window for Chandrayaan-3 will open on July 12 this year. All the tests around the mission have been completed and the launch vehicle has arrived at ISRO’s Satish Dhawan Space Centre (SDSC) in Sriharikota in preparation for the July launch.

The Chandrayaan program, also known as the Indian lunar exploration program, is an ongoing series of outer space missions by ISRO. The first moon rocket, Chandrayaan-1, was launched in 2008, and was successfully inserted into lunar orbit.

Chandrayaan-2 was successfully launched and inserted into the lunar orbit in 2019, but its lander “crash-landed” on the moon’s surface when it deviated from its trajectory while attempting to land on September 6, 2019, due to a “software glitch”, according to ISRO’s mission document.

In May, the space agency started the assembly process for the payloads for Chandrayaan-3, a move to ensure that the space agency is able to stick to the launch date of July, senior officials from the department of space said. The assembly happened at the UR Rao Satellite Centre (URSC) in Bengaluru, before it was sent to the Sriharikota space port for the launch.

Chandrayaan-3 consists of an indigenous lander module, a propulsion module and a rover. Its objectives include developing and demonstrating new technologies required for interplanetary missions. 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.

The main function of the propulsion module is to carry the lander module from launch vehicle injection till the final lunar 100km circular polar orbit and separate the lander module from the propulsion module. Apart from this, the propulsion module also has one scientific payload as a value addition, which will be operated post-separation of the lander module.

Chandrayaan-3 will be launched by Launch Vehicle Mark-3 (LVM3) rocket from Satish Dhawan Space Centre, Sriharikota. The propulsion module will carry the lander and rover configuration till the 100 km lunar orbit.

Aditya-L1

Aditya-L1, on the other hand, is India's first dedicated scientific mission to study the sun. Earlier, this mission was conceived as Aditya-1 with a 400kg class satellite carrying one payload, the VELC, and was planned to be launched in an 800km low earth orbit.

However, since a satellite placed in the halo orbit around the first Lagrangian Point (L1) of the sun-earth system has the major advantage of continuously viewing the sun without any occultation/eclipses, the Aditya-1 mission was renamed as Aditya-L1 mission, which will be inserted in a halo orbit around the L1—1.5 million km from the earth towards the sun.

This will provide a greater advantage of observing the solar activities and its effect on space weather in real time. The spacecraft will carry seven payloads to observe the photosphere, chromosphere and the outermost layers of the sun—the corona—using electromagnetic and particle and magnetic field detectors.

Scientists explained that using the special vantage point L1, four payloads directly view the sun, and the remaining three payloads carry out in-situ studies of particles and fields at the Lagrange point L1, thus providing important scientific studies of the propagatory effect of solar dynamics in the interplanetary medium. The primary objective of this mission is to study the solar upper atmospheric (chromosphere and corona) dynamics, chromospheric and coronal heating, physics of the partially ionised plasma, initiation of the coronal mass ejections, and flares.

ISRO officials said that after the Chandrayaan-3 mission, the next big-ticket project for the space agency will be Aditya-L1, which is likely to be scheduled for August this year.

Gaganyaan (Uncrewed And Crewed Missions)

ISRO’s Gaganyaan project envisages demonstration of human spaceflight capability by launching a crew of three members to an orbit of 400km for a three-day mission and bringing them back safely to earth, by landing in Indian sea waters. However, before India sends its selected astronauts to space, there will be a series of uncrewed tests—currently scheduled for early 2024—to ensure that the systems are safe for human travel.

“The project is accomplished through an optimal strategy by considering inhouse expertise, experience of Indian industry, intellectual capabilities of Indian academia and research institutions along with cutting edge technologies available with international agencies," ISRO said in its mission document.

“The prerequisites for Gaganyaan mission include development of many critical technologies including human rated launch vehicle for carrying crew safely to space, life support system to provide an earth like environment to crew in space, crew emergency escape provision and evolving crew management aspects for training, recovery and rehabilitation of crew,” the document stated.

The prerequisites for Gaganyaan mission include development of many critical technologies including human-rated launch vehicle for carrying crew safely to space, life support system to provide an earth-like environment to the crew in space, crew emergency escape provision and evolving crew management aspects for training, recovery and rehabilitation of crew.

Last month, the Indian Navy along with ISRO released a recovery training plan for India’s first human space flight mission at the Water Survival Training Facility at INS Garuda, Kochi. The space agency is hoping to complete its test vehicle missions and pad abort tests—two key tests for the mission—this year before the unmanned flights are conducted in the first quarter of 2024. The manned mission is expected to happen in the second half of next year, officials said.

NISAR

NASA-ISRO Synthetic Aperture Radar or NISAR as it is being called, is another mission to look forward to in 2024. This is the first time that National Aeronautics and Space Administration (NASA), the US civil space program, and ISRO are collaborating on an Earth-observing mission. NASA’s Jet Propulsion Laboratory (JPL) is leading the US part of the project and is providing the mission’s L-band SAR (synthetic aperture radar) and the radar reflector antenna, the deployable boom, a high-rate communication subsystem for science data, GPS receivers, a solid-state recorder, and payload data subsystem. ISRO is partnering to provide the spacecraft bus, the S-band SAR, the launch vehicle, and associated launch services and satellite mission operations.

“Once in operation, NISAR will be able to collect measurements day and night, in all weather conditions, and its trove of data will help researchers better understand a broad range of Earth science topics, including landslides, groundwater loss, and the carbon cycle," JPL said in a statement issued in February.

The US leg of the mission has been completed and the payloads were officially handed over to Isro early this year. After a few rounds of tests, the mission will be ready for launch “early next year”, ISRO scientists said.