India's Aditya-L1 Solar Mission Achieves Fourth Earth-bound Maneuver Success

In a significant milestone for India's Aditya-L1 spacecraft, the nation's inaugural space-based mission to explore the Sun, the spacecraft recently completed its fourth Earth-bound manoeuvre successfully, as reported by ISRO during the early hours of Friday.

ISRO, India's space agency, shared the update on X, formerly known as Twitter, stating, "The fourth Earth-bound manoeuvre (EBN#4) is performed successfully. ISRO's ground stations at Mauritius, Bengaluru, SDSC-SHAR, and Port Blair tracked the satellite during this operation, while a transportable terminal currently stationed in the Fiji islands for Aditya-L1 will support post-burn operations."

The spacecraft has now achieved a new orbit measuring 256 km x 121973 km. The next crucial step in its mission is the Trans-Lagrangean Point 1 Insertion (TL1I), scheduled for September 19, around 02:00 Hrs. IST. This manoeuvre marks the spacecraft's departure from Earth, commencing its approximately 110-day journey to reach the L1 Lagrange point, situated about 1.5 million km away from Earth.

Aditya-L1 is India's maiden space-based observatory dedicated to studying the Sun from a halo orbit around the Sun-Earth Lagrangian point L1. The preceding three Earth-bound manoeuvres took place on September 3, 5, and 10, all contributing to the spacecraft's velocity increment, crucial for its journey to L1.

Upon reaching the L1 point, Aditya L1 will be positioned in an orbit around L1, a gravitationally balanced point between the Earth and the Sun. From there, it will spend its mission orbiting L1 in an irregularly shaped path, perpendicular to the line joining the Earth and the Sun.

Aditya-L1's launch, facilitated by ISRO's Polar Satellite Launch Vehicle (PSLV-C57) on September 2, successfully positioned the spacecraft into an elliptical orbit of 235x19500 km around Earth. The unique advantage of Aditya-L1's position at the halo orbit around L1 is its uninterrupted view of the Sun, free from eclipses or occultation, enabling real-time observation of solar activities and their influence on space weather.

This groundbreaking mission carries seven scientific payloads, developed by ISRO and Indian research laboratories such as 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 explore the photosphere, chromosphere, and the Sun's outermost layers, the corona, using electromagnetic particle and magnetic field detectors.

Four of these payloads provide direct observations of the Sun, while the remaining three conduct in-situ studies of particles and fields at the Lagrange point L1. Together, these payloads offer invaluable insights into coronal heating, coronal mass ejections, flare activities, space weather dynamics, and the propagation of particles and fields.

Scientists emphasize that there are five Lagrangian points, named after Joseph-Louis Lagrange, where objects can stay with minimal fuel consumption due to the balanced gravitational forces between the Sun and the Earth. Aditya-L1's location at L1 optimizes its scientific observations while conserving energy.