Halo-Orbit Insertion (HOI) of its solar observatory spacecraft, Aditya-L1 was accomplished at 16.00 Hrs (approx) on January 6, 2024 (IST). The final phase of the maneuver involved firing of control engines for a short duration.
Halo – Orbit
- The orbit of Aditya-L1 spacecraft is a periodic Halo orbit which is located roughly 1.5 million km from earth on the continuously moving Sun – Earth line with an orbital period of about 177.86 earth days.
- It has covered only 1 per cent of the distance to the Sun.This Halo orbit is a periodic, three-dimensional orbit at L1 involving Sun, Earth and a spacecraft.
- This specific halo orbit is selected to ensure a mission lifetime of 5 years, minimising station-keeping manoeuvres and thus fuel consumption and ensuring a continuous, unobstructed view of sun.
The Aditya-L1 mission is an Indian solar observatory at Lagrangian point L1 for “Observing and understanding the chromospheric and coronal dynamics of the Sun” in a continuous manner. Placing the Aditya-L1 in a halo orbit around L1 point has advantages as compared to placing in a Low Earth Orbit (LEO):
- It provides a smooth Sun-spacecraft velocity change throughout the orbit, appropriate for helioseismology.
- It is outside of the magnetosphere of Earth, thus suitable for the “in situ” sampling of the solar wind and particles.
It allows unobstructed, continuous observation of the Sun, and view of earth for enabling continuous communication to ground stations.