India is about to begin the second moon mission – if it succeeds, it will become the fourth country to make a soft landing on the surface of the moon.
Only the United States, China and the former Soviet Union were able to do so.
The $ 150 million mission – Chandrayaan-2 – aims to collect data on water, minerals and rock formations on the moon.
The lander and rover are expected to meet near the south pole of the Moon at the beginning of September, becoming the first ever spacecraft to land in the region.
The head of the Indian Space Research Organization (Isro), K Sivan, said it was "the most complex space mission ever performed by an agency."
The satellite manufactured in India is expected to be launched at 02:51 local time on Monday (21:21 GMT Sunday) from the Sriharikota space station on the east coast of India.
The first lunar mission of the country in 2008 – Chandrayaan-1 – did not land on the surface of the Moon, but carried out the first and most detailed search of the water on the moon using radar.
What is this mission about?
Chandrayaan-2 (Lunar Vehicle 2) will attempt a soft landing near the underdeveloped south pole of the Moon.
The mission will focus on the surface of the Moon, looking for water and minerals and measuring moonquakes, among other things.
In this mission, India uses its most powerful rocket, Geosynchronous Satellite Vehicle Mark III (GSLV Mk-III). It weighs 640 tons (almost 1.5 times more than a fully laden 747 jumbo jet), and at 44 meters (144 ft) it is as tall as a 14-story building.
The probe weighs 2,379 kg (5,244 pounds) and consists of three separate parts: the orbiter, lander and rover.
The orbiter, who has a year of mission, will take pictures of the moon's surface and "sniff" the delicate atmosphere.
The lander (named Vikram, after the founder of Isro) weighs half as much and wears a 27-kilo lunar rover in the stomach with instruments to analyze the lunar soil. In its 14-day life, a rover (called Pragyan – Sanskrit wisdom) can travel up to half a kilometer from the lander and transfer data and images back to Earth for analysis.
"India can count on the first self-portraits from the surface of the Moon when the rover starts working," said Dr. Sivan.
A new boundary for the Indian space program
Author of the study of Pallava Bagla
A soft landing on another planetary body – a feat achieved so far only by three other countries – would be a huge technological achievement for Isro and India's cosmic ambitions.
This would pave the way for future Indian missions to land on Mars and the asteroid. More importantly, it would open up the possibility for India to send astronauts to the moon. India hopes to conduct a manned space flight by 2022.
India also wants to gain a cosmic power to be reckoned with – and the national pride goes high because it aims to raise its flag on the surface of the moon.
A successful mission on the Moon would also be the victory of India's ambitious space agency, which has recently been successful.
In 2014, it successfully placed a satellite in orbit around Mars, becoming the fourth country to do so. In 2017, India created history, successfully launching 104 satellites as part of one mission, ahead of the previous record of 37 satellites launched by Russia in 2014.
All eyes look at Isro again. According to Simonetta Di Pippo, director of the United Nations office for space, global interest in the economical mission of the Moon in India is reaching its peak.
"Studies of the mission of the lunar topography, mineralogy, elemental abundance, moon exosphere and signatures of hydroxyl and water ice will contribute to the scientific progress of all mankind," he says.
The Indian cosmic community is upset, and Dr. Sivan says: "He's boiling in his stomach."
"Unknown unknowns can kill a mission, [although] no stone has been inverted to understand all the intricacies. "
How long does it take to travel to the moon?
Launching is just the beginning of a journey of 384,000 km (239,000 miles) – it is expected that the robots will make a landing on the Moon some 54 days later on September 6 or 7.
Isro has chosen a circuitous route to take advantage of Earth's gravity, which will help to shoot the satellite towards the moon. India does not have enough rocket to throw Chandrayaan-2 on the direct path.
'The scientists will have 15 frightening minutes when the lander will be released and will be thrown towards the South Pole of the Moon,' says Dr Sivan.
He explains that those who controlled the spacecraft until then will not play any role in these key moments. He adds that the actual landing is an autonomous operation dependent on all systems operating as they should. Otherwise, the lander could collide with the surface of the Moon.
Earlier this year, the first lunar mission in Israel landed during a landing attempt.
Who is in the team?
Almost 1,000 engineers and scientists have worked on this mission. But for the first time, Isro chose women for an interplanetary expedition.
Two women guide India's journey to the moon. While program director Muthaya Vanith has been cultivating Chandrayaan-2 for years, it will be touched by Ritu Karidhal.
"The power of women drives the Moon's ambition in India," said Dr. Sivan, adding that in Isro "women and men are equal. Only talents count – not sex ".
Reporting by Pallava Bagli, who wrote extensively about the Indian space program.