Chandrayaan-3: All eyes on Vikram lander, Pragyan as ISRO awaits them to wake up from slumber

As dawn breaks on the moon on Friday, the Indian Space Research Organisation (ISRO) keenly awaits Chandrayaan-3’s Vikram Lander and Pragyan Rover to wake up from their 14-day lunar slumber. If they wake up, the second phase of Chandrayaan-3 will begin.

The lander and rover modules Vikram and Pragyan were put on sleep on September 4 around 8 am after night descended on the moon. The temperature then plunges to over -130° C, the poles even colder. To survive the extremely frigid atmosphere at the south pole of the moon, the rover had to be put to sleep. 

However, their battery is now fully charged, with the rover’s solar panel geared to receive light as the sun rises. As soon as the temperature on the moon rises to above minus 10 degrees Celsius, a condition that will activate the vital communication circuit known as the “wake-up circuit.”

“Our communication circuit (with the lander and rover) has to get activated. The communication circuit is called the wake-up circuit. It will work when the temperature rises to minus 10 degrees. Now team ISRO and everyone connected to the mission are waiting for the temperature to rise on the moon,” Union Minister Jitendra Singh said on Thursday.

“This will happen for the first time in the world. Tomorrow, when the country will celebrate the passage of the women’s reservation bill, perhaps, we will also have the opportunity to celebrate the occasion of the waking up of Vikram and Pragyan,” the minister said.

“The second phase of Chandrayaan-3 is about to take off in the next few hours. The moment of anxiety is that we are waiting for the wake-up call to get activated and Vikram and Pragyan to respond to that alarm. Once they do, the communication from the earth will begin and we will be the first in the world to have accomplished this,” Singh said.

However, the agency gave no specific conclusion as to whether Pragyan will ever work again or not. 

The Pragyan rover is a small, 26-kilogram robot that is about 36 inches long. It has a rectangular chassis with a solar array that can generate 50 watts of power. “The rover has a small battery that helps it deploy its solar array, but, after that, it runs solely on solar power. The rover’s electric motor makes maximum torque as soon as it starts to turn, which helps it move around on the lunar surface,” explained space expert Girish Linganna.