ISRO scripts history, Aditya-L1 successfully inserted in Halo-Orbit

Chennai: Marking a major achievement in India’s space odyssey, the Indian Space Research Organisation (ISRO) created history on Saturday by successfully inserting its first Solar exploratory mission spacecraft Aditya-L1 in the halo orbit at Lagrange-L1 point.
After completing a four month long voyage and traversing 1.5 million km, it reached the L1 point Saturday evening at around 1600 hrs, ISRO said. “Halo-Orbit Insertion (HOI) of its solar observatory spacecraft, Aditya-L1 was accomplished at 1600 hrs (approx) on January 6, 2024 (IST)”, it said. The final phase of the maneuver involved firing of control engines for a short duration.
India became the first country in the world to achieve this accomplishment to study the outer atmosphere of the most hottest planet. Scientists at the ISRO Telemetry, Tracking and Command Network (ISTRAC) fired the LAM motors on board the spacecraft to take it to the Sun-Earth Lagrange Point L1 in a halo orbit.
President Draupady Murmu, Prime Minister Narendra Modi and Union Minister Jitendra Singh lauded ISRO for achieving this extraordinary feat. In a post on X, Ms Murmu said yet another grand feat was achieved by ISRO. “Another grand feat accomplished by ISRO! As part of India’s maiden solar mission, Aditya L1, the observatory has been placed in the final orbit and reached its destination at Lagrange Point 1.” “Congratulations to the entire Indian scientist community for the great achievement!”, she added. This mission will enhance our knowledge of the Sun-Earth System and benefit the entire humanity, the President said. She also said that significant participation of women scientists in ISRO missions takes women empowerment too onto a higher orbit. Modi posted “India creates yet another landmark.”
“India’s first solar observatory Aditya-L1 reaches it’s destination. It is a testament to the relentless dedication of our scientists in realising among the most complex and intricate space missions. I join the nation in applauding this extraordinary feat. We will continue to pursue new frontiers of science for the benefit of humanity,” Mr Modi posted on X
As the spacecraft travelled towards L1, it exit the Earths’ gravitational Sphere of Influence (SOI). After its exit from SOI, the cruise phase started and subsequently the spacecraft was injected into a large halo orbit around L1.
The total travel time from launch to L1 took about four months for Aditya-L1. Upon arrival at the L1 point, another manoeuvre binds Aditya-L1 to an orbit around L1, a balanced gravitational location between the Earth and the Sun. This will be the second major achievement for the Indian Space Agency after its third Lunar Mission Chandrayaan-3 successfully landed on the Moon’s South Polar region, an hitherto unexplored area.
The Space agency said India’s maiden solar mission Aditya L1 reached the L1 point on January 6, 127 days after it was launched on September 2, 2023. Aditya-L1 the first Indian space based observatory to study the Sun was launched on September 2, 2023 from the Satish Dhawan Space Centre in Sriharikota. Subsequently, ISTRAC carried out four earth-bound manoeuvres between September 3 and September 15. Aditya-L1 on September 19 underwent the Trans-Lagrangian 1 insertion manoeuvre, marking the beginning of its 110-day trajectory to the destination around the L1 point. L1 is roughly about 1.5 million km from the Earth and the distance of L1 from Earth is approximately 1% of the Earth-Sun distance.
With the Aditya-L1 satellite placed in the halo orbit around the L1 point it will be continuously viewing the Sun without any occultation/eclipse. This will provide a greater advantage of observing the solar activities continuously. Aditya-L1 carries seven payloads to observe the photosphere, chromosphere, and the outermost layers of the Sun (the corona) using electromagnetic and particle detectors. Using the special vantage point of L1, four payloads will directly view the Sun and the remaining three payloads will carry out in-situ studies of particles and fields at the L1. With a mission life of fie years, Aditya-L1 payloads are expected to provide the most crucial information to understand the problem of coronal heating; coronal mass ejection; pre-flare and flare activities and their characteristics; dynamics of space weather; and propagation of particles and fields.