How Chandrayaan-3's Final "20 Minutes Of Terror" Played Out

India made history at 6.04 pm this evening after Chandrayaan-3 completed a soft landing on the Moon's surface, becoming only the fourth nation - after Russia (then the Soviet Republic), the United States and China - to achieve this feat. The touchdown process of the Vikram lander - which contains the Pragya rover that will operate on the lunar surface for 14 days, gathering valuable scientific data - began at 5.47 pm, triggering the '20 minutes of terror'.

Shortly before Chandrayaan-3's Vikram lander began landing, the legion of scientists at the Indian Space Research Organisation triggered the 'power descent' phase, which referred to an automated landing sequence carried out by the lander with no help from Mission Control.

Chandrayaan-3's Automated Landing Sequence

The 'power descent' phase consists of four stages.

The first is the 'rough braking' phase, which reduces the Vikram lander's horizontal speed from 1.68 km per second (over 6,000 km per hour) to nearly zero. This is a critical phase since the lander must scrub high speeds in a very short space of time to ensure a perfect landing.

The second is the 'attitude hold' phase, which lasts for around 10 seconds only. In this phase the Vikram lander remains at a pre-set altitude of 7.42 km while it begins to tilt from a horizontal to vertical position. In this phase the spacecraft covers around 3.48 km.

LIVE COVERAGE |India Makes History, Becomes 4th Nation To Land On Moon

The third phase is the 'fine braking' phase and this is the longest of the four, lasting over 175 seconds. In this phase Vikram lander will travel the final 28-odd km to the Moon's surface while continuing to manouvre into an upright position. The 'nominal speed' at this time is zero metres per second and the altitude will come down to around 800-1000 metres.

Crucially, it was in-between the second and third phases Chandrayaan-2 crashed.

The final phase is the 'terminal descent' in which the lander travels the final few hundred metres to the Moon's surface.

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Chandrayaan-3 On The Moon. What Next?

Now that Chandrayaan-3 is on the lunar surface - a historic feat matched only by three other countries with vastly greater resources - all eyes will be on the Pragyan rover, which is contained within the lander.

The rover will be released around three hours after the landing because the lunar dust kicked up by the landing needs to disperse in order to ensure the rover or the many instruments on board are not damaged.