India launched its second mission to the Moon on 22 July, a week after it halted a launch attempt because of a leak in the carrier rocket’s engine.
The 3.9-tonne Chandrayaan-2 spacecraft lifted off on an Indian Geosynchronous Satellite Launch Vehicle rocket from a site on the edge of the Bay of Bengal. The US$141-million mission marks India’s first attempt to make a ‘soft’ landing on the Moon — a feat so far achieved only by the United States, Russia and China.
The spacecraft is heading for the south pole, an uncharted part of the lunar surface, where it will study rocks, soil and minerals.
“We will explore the unexplored,” said Indian Space Research Organisation (ISRO) chair K. Sivan in a statement from mission control after the launch. Sivan said that after detecting a serious technical snag during the launch countdown on 15 July, ISRO had fixed the problem and “bounced back with flying colours”.
Chandrayaan-2 comprises a lunar orbiter, lander and rover, and is loaded with 14 scientific instruments — 13 from India and one from NASA. The lander, called Vikram, is scheduled to touch down on 7 September and will function for one lunar day — 14 Earth days — during which time it will release a six-wheeled rover called Pragyan that will explore for a distance of up to 500 metres at a speed of 1 centimetre per second. The orbiter will circle the Moon for one year in a path that will take it over the poles.
Of the 13 Indian instruments, 8 are on the orbiter, 3 on the lander and 2 on the rover. They include stereoscopic and high-resolution cameras; X-ray, infrared and mass spectrometers; and radar. Together, the instruments will probe lunar rocks, soils and the atmosphere — as well as searching for water and identifying minerals containing elements such as magnesium, iron and calcium.
The NASA contribution, which is on the lander, is an array of mirrors that will reflect laser beams from Earth and help to calculate the distance to the Moon.
“This will be the first landed mission to explore the south polar region of the Moon. This is advantageous for studying the presence of volatiles, especially water ice, at low latitudes,” says Ryan Watkins, a lunar scientist at the Planetary Science Institute in Tucson, Arizona. “The poles may contain vast amounts of resources — water, oxygen, hydrogen — that could be used for future exploration,” she adds. Missions from the three other countries that have made it to the Moon all landed near the equator.
Chandrayaan-2 comes 11 years after India’s first Moon mission launched, in 2008. Chandrayaan-1 was an orbiter that carried 11 instruments, from Europe India and the United States. In 2018, data from one of the NASA instruments on Chandrayaan-1, a mineralogy mapper, helped to directly detect the presence of ice on the Moon.