Mission sun: ISRO's Aditya L1 spacecraft to perform key manoeuvre today. What if the spacecraft misses halo orbit?

The Indian Space Research Organisation (ISRO) will execute a key manoeuvre today. Aditya L1 spacecraft will receive a command from India's first space based solar observatory that is 15 lakh kilometres away to move to designated orbit. What will happen during the final orbit manoeuvre? Former ISRO scientist and founder of NIMBUS Education, Manish Purohit who exercises expertise in critical space missions like Chandrayaan 2 and Mangalyaan informed HT that during the manoeuvre a 180 degree flip of the spacecraft is performed.

This brings the thrusters to the front to slow down the spacecraft while aiming for a different orbit. This manoeuvre will last only a few seconds. Aditya L1's liquid apogee motors are currently in a hibernated state due to the cold space environment, since its last firing that was a couple of months ago.

When ISRO will commanded the motors, they will instantly fire for the specific duration and perform the manoeuvre precisely at that particular moment. However, this execution requires precision to avoid overdoing, underdoing or mistiming the motor firing. Aditya L1 will face challenges arising out of the complex 3D nature of this orbit following manoeuvre into halo orbit.

The halo orbit is highly complex as it revolves around the dynamically moving L1 point. The L1 point is constantly in motion along the earth sun line. Thus, Aditya orbits a non stationary point that changes position with Earth's movement around the sun. Control moment gyros are used in AdityaL1 that help balance the spin.

These gyros are similar to those used by the International Space Station for orientation. Moreover, the spacecraft's software continuously monitors position parameters and orbital details with ground stations. What will happen if the manoeuvre fails? If the spacecraft fails to perform the manoeuvre in case of overfiring or underfiring of the engine and misses the sweet spot in the expected orbit range then there would be trouble.

The spacecraft may miss the gravity capture by the L1 point and enter a higher orbit throwing it off the desired orbit. This would lead to higher fuel consumption which is very crucial for longer mission life. Livemint tops charts as the fastest growing news website in the world to know more. Unlock a world of Benefits! From insightful newsletters to real time stock tracking, breaking news and a personalized newsfeed – it's all here, just a click away!.