Carrying a billion dreams, Chandrayaan-3 to blast off on July 14

Chandrayaan-3, India’s third unmanned moon mission with a precise goal of making a soft and safe landing on the lunar surface, will blast off at 2:35 pm on Friday from the second launchpad of the Sathish Dhawan Space Centre in Sriharikota. The mission’s success will enable India to join the elite club of nations such as the US, Russia, and China that have achieved the feat in the past, besides fast-tracking its manned mission to the moon.

The weather in Sriharikota, 100 km from Chennai, is expected to be cloudy, but the forecast says the possibility of rains are remote, in good news for the Indian Space Research Organisation (ISRO) which has been working on the ambitious project since 2020.

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In a bid to seek divine intervention, scientists offered special prayers at the famous Lord Venkateshwara Temple in Tirupati with a miniature model of the rocket and spacecraft and sought blessings, while ISRO chief S Somnath prayed obeisance at the Chengalamman Temple in Sullurpet on his way to Sriharikota.

India’s largest and heaviest launch vehicle, LVM3-M4, will launch the 3,900-kg Chandrayaan-3 spacecraft, including the lander, to the Geo Transfer orbit after it takes off from the second launchpad at 2.35 pm as planned. ISRO said the 25 hour-30 minute countdown for the much-awaited launch began Thursday afternoon.

Billed as a follow-up mission to Chandrayaan-2, which failed after the lander crash-landed on the moon after 48 days of its launch in July 2019, Chandrayaan-3 will seek to demonstrate end-to-end landing and roving capabilities. The spacecraft will take about 42 days to make a soft landing on the lunar surface which is expected to be between August 23 and 24, six days lesser than the Chandrayaan-2 mission took.

India’s first unmanned mission, Chandrayaan-1, which took off on October 22, 2008, demonstrated the country’s ability to reach the surface of the moon and discover water on the lunar surface, the Chandrayaan-2 mission was to make a soft landing on the moon, which failed.

Learning lessons from the failure, the ISRO has made several significant modifications to Friday's mission with officials attributing the 2019 failure to malfunctioning of the onboard computer and propulsion system.

This time around, the lander’s legs have been strengthened, a fifth engine has been removed to reduce the weight, and the landing area has been expanded from 500mx500m (in Chandrayaan-2) to 4kmx2.4 km area in Chandrayaan-3. Several special tests like Integrated Cold and Integrated Hot tests and Lander Leg mechanism performance tests have also been conducted to ensure the success of the mission, the officials added.

The Chandrayaan-3 mission is yet another attempt to achieve the goal with the help of a rover. The spacecraft, according to officials, will have four payloads which will study moon quakes, as to how the surface of the moon allows heat to flow through it, the plasma environment near the moon surface, and enable scientists to measure the distance between earth and moon “very accurately.”

The two rover payloads study composition of the moon’s surface using X-rays and LASER, while the propulsion module payload will explore the Spectro-polarimetric signatures of the habitable planet, Earth. The mission is divided into three phases -- Earth Centric, Lunar Transfer, and Moon Centric.

The Chandrayaan-3 lander carrying a rover within it will be carried into an orbit around the moon by the propulsion module. A little later, the lander will separate from that module and will attempt to make a soft landing in the south polar region of the moon, which is of intense interest as it has many permanently shadowed craters which could contain water ice and precious minerals.

The work on Chandrayaan-3 began just a few months after the failure of Chandrayaan-2, but the Covid-19 pandemic and the subsequent lockdown delayed ISRO’s plans. By demonstrating its capabilities to soft land on the moon, the ISRO is also hoping to expand its business as it is already launching private satellites from Sriharikota.