ISRO’s Aditya-L1 Completes First Halo Orbit Around Sun-Earth L1 Point in 178 Days

India’s first solar mission, the Aditya-L1 spacecraft, has successfully completed its first halo orbit around the Sun-Earth L1 point, as announced by the Indian Space Research Organisation (ISRO) on Tuesday.

The Aditya-L1 mission, an Indian solar observatory positioned at the Lagrangian point L1, was launched on September 2 last year and entered its designated halo orbit on January 6.

The spacecraft takes 178 days to complete one revolution around the L1 point while in the halo orbit.

During its journey in the halo orbit, the spacecraft encounters various forces that can push it away from its intended path, according to ISRO.

To maintain its orbit, the spacecraft underwent two station-keeping maneuvers on February 22 and June 7.

The third station-keeping maneuver, conducted today, has ensured that the spacecraft continues its journey into the second halo orbit around L1.

“This journey of Aditya L1 around the Sun-Earth L1 Lagrangian point involves modeling complex dynamics,” ISRO stated.

Understanding the different forces acting on the spacecraft helped in accurately determining its trajectory and planning precise orbit maneuvers.

With today’s maneuver, the advanced flight dynamics software developed in-house at URSC-ISRO for the Aditya-L1 mission has been fully validated, according to ISRO.

ISRO also provided details of the trajectories shown in a figure.

The blue trajectory in the figure represents the orbit around the Lagrangian point L1. This trajectory is three-dimensional, and the figure shows its projection in the X-Y plane.

“SK#1, 2 & 3 are the Station Keeping maneuvers by the Aditya-L1 spacecraft. The final thruster firing, SK#3 on July 2, placed the spacecraft back in the required orbit,” ISRO stated.

Additionally, if the thruster firing had not been accurate, the spacecraft would have moved away along a trajectory shown in green.

The X-Y axes in the figure are marked in kilometers, with the Lagrangian point L1 at the origin, ISRO added.