India’s lunar rover will face its next big challenge – surviving the lunar night
The sun sets on Pirjayan, the history-making lunar rover sent to the lunar surface by the Indian Space Research Organization (ISRO), along with the Vikram lander. The indomitable duo has completed their primary mission, providing interesting insights, and now it’s time to sleep. Unfortunately, this is just an afternoon nap and Bragyan will be up in two weeks ready to go again.
“The vehicle has completed its missions. It is now safely parked and has entered sleep mode,” ISRO said in a statement. “Currently, the battery is fully charged. The solar panel is oriented to receive the light at the next sunrise expected on September 22, 2023. The receiver is being held. Hoping for a successful wake-up for another set of missions!”
This was always part of the plan, as Braggian’s science mission was always going to be one lunar day, or 14 Earth days. A lunar day is about 29.5 Earth days, meaning there are just over 14 sunny days and just over 14 days of night. During the night, the temperature drops to -130°C (-208°F), which can damage hardware. In many missions, energy is used to keep the system warm enough to survive. But without sunlight, the rover uses energy stored in the batteries, and they run the risk of running out before they have a chance to charge again.
However, ISRO was prepared to give Bragyan a fighting chance. The ISRO team fully charged the two tower batteries and pointed its solar panel to get the first sunlight on September 22. His two experiments were stopped and all data was transmitted back to Earth. Everything that could be done was done to ensure non-eternal sleep. Now we just have to wait and see.
“Hope for a successful awakening to another set of missions! “Otherwise she will stay there forever as India’s ambassador to the moon,” ISRO wrote on X (formerly Twitter) over the weekend.
The space agency also confirmed that the Vikram lander was set to enter sleep mode. But just before that, Vikram does a bunny hop. It flew 40 cm (15.8 in) and then landed safely about 40 cm away. The tools were stored safely and then redeployed. Measurements were taken at the new location, before all data was sent back to Earth.
“The Vikram Lander was put to sleep at approximately 08:00 AM IST today. Prior to that, on-site trials were carried out by ChaSTE, RAMBHA-LP and ILSA payloads at the new site. The data collected is being received on the ground,” ISRO confirmed at a tweet.
“The loads are now off. The touchdown receivers are being kept on. Vikram will sleep next to Pragyan once the solar runs out and the battery runs out. Hopefully they will wake up around September 22, 2023.”
India’s first soft landing on the moon has been a huge success. They were the first to safely reach the region around the south pole of the Moon, a place of great interest to space agencies. We hope that both the lander and the rover will wake up again and move on to an extended mission, providing more scientific discoveries.