ISRO’s Aditya-L1 successfully placed in a halo orbit around L1 point

India’s maiden solar mission Aditya-L1 reached the L1 point, 127 days after it was launched. The point is located roughly 1.5 million km from earth and enables the spacecraft to view the sun continuously.

The Indian Space Research Organisation (ISRO) achieved a significant milestone as the Aditya-L1 spacecraft reached its destination, placing it in a halo orbit around the Lagrangian point (L1). This accomplishment comes 127 days after the spacecraft's launch on September 2, 2023.

Chronology of Events:

1. Launch of Aditya-L1 :
• Aditya-L1, India's first solar mission, was launched from the Satish Dhawan Space Centre in Sriharikota.
• The primary objective was to study the sun, making it a crucial mission for advancing solar observational capabilities.
2. Earth-Bound Manoeuvres:
• ISRO's Telemetry Tracking and Command Network (ISTRAC) executed four earth-bound manoeuvres to set the spacecraft on its trajectory.
3. Trans-Lagrangian 1 Insertion Manoeuvre:
• Aditya-L1 underwent the Trans-Lagrangian 1 insertion manoeuvre, initiating its 110-day trajectory towards the Lagrangian point.
4. Arrival at Lagrangian Point:
• After a 1.5-million km journey, the spacecraft reached the Lagrangian point.
• ISRO scientists and engineers at ISTRAC in Bengaluru conducted a firing manoeuvre to place Aditya-L1 in a precise halo orbit around L1.
5. Halo Orbit Insertion:
• The halo orbit insertion process was successfully carried out, ensuring the spacecraft's precise placement around L1.
• ISRO Chairman S Somnath emphasized the critical nature of the manoeuvre for avoiding potential deviations.
6. Prime Minister's Announcement (January 6, 2024):
• Prime Minister Narendra Modi announced the successful arrival of Aditya-L1 at its destination, praising the dedication of Indian scientists.

Details of Halo Orbit and Lagrangian Point:

• Halo Orbit Characteristics:
• The Aditya-L1 is in a periodic halo orbit approximately 1.5 million km from Earth, maintaining a continuously moving Sun-Earth line.
• This three-dimensional orbit involves the Sun, Earth, and the spacecraft, ensuring unobstructed views of the Sun.
• Lagrangian Point (L1):
• L1 is situated between the Sun and Earth, about 1% of the Earth-Sun distance.
• Satellites placed at L1 experience reduced fuel consumption, making it an advantageous position for observational spacecraft.

Significance of Aditya-L1 Mission:

• Aditya-L1 is the first Indian space-based observatory dedicated to studying the Sun.
• The satellite carries seven payloads to observe the photosphere, chromosphere, and the outermost layer of the Sun (corona) using electromagnetic and particle detectors.

ISRO's Success in Complex Orbital Manoeuvres:

• The precision in placing Aditya-L1 in the halo orbit highlights ISRO's capabilities in executing complex orbital manoeuvres.
• Confidence in handling such intricate missions sets the stage for future interplanetary missions.

Way Forward:

• The successful placement of Aditya-L1 in the halo orbit around L1 marks a significant achievement for India's space exploration
• This mission holds the promise of advancing our understanding of solar activities and contributing crucial data to space science.’