India\’s pioneering solar-focused spacecraft, Aditya L1, achieved a successful execution of its fourth Earth-bound maneuver during the early hours of Friday, according to ISRO\’s confirmation.
ISRO announced, \”The fourth Earth-bound maneuver (EBN#4) has been successfully completed. ISRO\’s ground stations in Mauritius, Bengaluru, SDSC-SHAR, and Port Blair diligently tracked the satellite during this operation, with additional support from a transportable terminal stationed in the Fiji Islands for Aditya-L1\’s post-burn operations.\” This announcement was made via the X platform, previously known as Twitter.
The recently achieved orbit measures 256 km x 121973 km. ISRO also shared that the next critical step, the \”Trans-Lagrangean Point 1 Insertion (TL1I),\” marking the spacecraft\’s departure from Earth, is scheduled for September 19 at approximately 02:00 Hrs. IST. Aditya-L1 serves as India\’s inaugural space-based solar observatory, tasked with studying the Sun from a halo orbit encompassing the first Sun-Earth Lagrangian point (L1), located at a distance of approximately 1.5 million km from Earth.
The initial three Earth-bound maneuvers were successfully conducted on September 3, 5, and 10.
These maneuvers play a crucial role in propelling the spacecraft during its 16-day journey around Earth, allowing it to gain the necessary velocity for its subsequent voyage to L1.
With the completion of the fourth Earth-bound orbital maneuver, Aditya-L1 will soon undergo a Trans-Lagrangian1 insertion maneuver, commencing its approximately 110-day trajectory toward its destination at the L1 Lagrange point.
Upon reaching the L1 point, another maneuver will secure Aditya L1 into an orbit around L1, a gravitational equilibrium point located between Earth and the Sun. The satellite will spend its entire mission orbiting L1 in an irregularly shaped path, oriented at an angle roughly perpendicular to the line connecting Earth and the Sun.
Aditya-L1 was successfully launched by ISRO\’s Polar Satellite Launch Vehicle (PSLV-C57) on September 2 from the Second Launch Pad at the Satish Dhawan Space Centre (SDSC), Sriharikota. Following a 63-minute and 20-second journey, the spacecraft was placed into an elliptical orbit measuring 235×19500 km around Earth.
Placing a spacecraft in a halo orbit around the L1 point offers a significant advantage as it enables continuous observation of the Sun without disruptions or eclipses. This unique vantage point enhances the study of solar activities and their impact on real-time space weather.
Aditya-L1 is equipped with seven scientific payloads developed by ISRO and national research institutions, including the Indian Institute of Astrophysics (IIA) in Bengaluru and the Inter-University Centre for Astronomy and Astrophysics (IUCAA) in Pune. These payloads are designed to observe the photosphere, chromosphere, and the Sun\’s outermost layers, the corona, using electromagnetic particle and magnetic field detectors.
Of these payloads, four directly observe the Sun from the advantageous L1 position, while the remaining three perform in-situ studies of particles and fields at Lagrange point L1. These investigations contribute vital scientific insights into solar dynamics in the interplanetary medium, including phenomena such as coronal heating, coronal mass ejections, pre-flare and flare activities, space weather dynamics, and the propagation of particles and fields.
Scientists explain that there are five Lagrangian points, also referred to as parking zones, situated between the Earth and the Sun, where a small object naturally remains when placed there. These points, named after the Italian-French mathematician Joseph-Louis Lagrange for his influential 1772 paper, \”Essai sur le Probleme des Trois Corps,\” offer spacecraft the opportunity to maintain their position with minimal fuel consumption. At these Lagrange points, the gravitational forces of the Sun and the Earth balance with the necessary centripetal force required for a small object to remain synchronized with them.