The journey of ISRO's Aditya-L1's journey to the Lagrange-1 point

A successful insertion also required ongoing monitoring, as well as adjustments to the spacecraft's speed and position via onboard thrusters.

After the success of the country's lunar mission Chandrayaan-3 in August, in which ISRO successfully placed the 'Vikram' lander on the moon's south pole, the Aditya spacecraft arrived at its final destination to study the Sun on January 6.

The Aditya-L1 spacecraft is in a periodic Halo orbit about 1.5 million kilometres from Earth on the continuously moving Sun-Earth line, with an orbital period of around 177.86 Earth days. This Halo orbit is a three-dimensional, periodic orbit at L1 including the Sun, Earth, and a spacecraft. This particular halo orbit was chosen to assure a 5-year mission lifesapan by reducing station-keeping movements and consequently fuel consumption and ensuring a continuous, unimpeded view of the sun.

Following is the chronology of events related to Aditya L1. September 2, 2023:

ISRO launches Aditya-L1 onboard PSLV-C57.

September 2, 2023: ISRO launched Aditya-L1 onboard PSLV-C57.

September 3: First Earth-bound maneuver performed successfully, attaining an orbit of 245 km x 22459 km.

September 5: Second Earth-bound maneuver performed successfully. The new orbit attained was 282 km x 40225 km.

September 10: Third Earth-bound manoeuvre attains new orbit of 296 km x 71767 km.

Setpember 15: Fourth Earth-bound manoeuvre to achieve new orbit 256 km x 121973 km performed successfully.

September 18: Aditya-L1 commenced the collection of scientific data.

September 30: The spacecraft escaped the sphere of Earth’s influence and goes on its way to the Sun-Earth Lagrange Point 1(L1).

October 6 :Trajectory Correction Manoeuvre (TCM) was performed for about 16 seconds to correct the trajectory. TCM enured the spacecraft was on its intended path towards the Halo orbit insertion around L1.

November 7: HEL1OS payload captured first High-Energy X-ray glimpse of Solar Flares.

December 1: Solar wind Ion Spectrometer (SWIS) in the Aditya Solar wind Particle Experiment(ASPEX) payload was made operational.

December 10: The SUIT payload captures full-disk images of the Sun in near ultraviolet wavelengths.

January 6, 2024: India’s first solar observatory Aditya-L1 reaches its destination.

The insertion of Aditya-L1 in the Halo orbit represents a vital mission milestone that required precision navigation and control. A successful insertion also required ongoing monitoring, as well as adjustments to the spacecraft's speed and position via onboard thrusters. The achievement of this insertion not only proved ISRO's capabilities in such difficult orbital movements, but it also assured future interplanetary missions.

(With inputs from news agencies.)