As it performed a crucial manoeuvre in the early hours of Tuesday, the Aditya L1 spacecraft, India’s first space-based mission to study the Sun, received a “send-off” from the Earth after circling it since its launch on September 2.
The spacecraft’s approximately 110-day route to the target orbiting the L1 Lagrange point, a balanced gravitational position between the Earth and the Sun, begins with the Trans-Lagrangian Point 1 Insertion manoeuvre.
“Off to Sun-Earth L1 point! Successful completion of the Trans-Lagrangian Point 1 Insertion (TL1I) manoeuvre. The spacecraft is now travelling towards the Sun-Earth L1 point. After around 110 days, it will be manoeuvred into an orbit around L1 by ISRO, according to a post on X (formerly Twitter).
According to the country’s space agency, this is the sixth time in a row that the Indian Space Research Organisation (ISRO) has successfully transported an item on a trajectory towards another celestial body or place in space.
Aditya-L1, the first space-based observatory from India, is the first observatory to study the Sun from a halo orbit around the first Sun-Earth Lagrangian point (L1), which is about 1.5 million kilometres (km) from Earth and represents about 1% of the Earth-Sun distance.
Aditya-L1 would investigate the Sun’s outer atmosphere since the Sun is a massive disc of gas. Neither will it touch down on the Sun nor get any closer. Aditya-L1 has completed four Earth-bound manoeuvres since its launch on September 3, 5, 10, and 15, respectively. During these manoeuvres, it obtained the necessary velocity for its remaining voyage to L1.
Aditya-L1 is forced into an orbit around L1 after arriving at the L1 point by another manoeuvre. The satellite spends the entirety of its mission life in an erratic orbit around L1 in a plane that is nearly perpendicular to the line connecting the Earth and the Sun. ISRO had announced shortly after the launch that Aditya-L1 will take roughly 127 days to reach the desired orbit at the L1 point.
On September 2, the Aditya-L1 spacecraft was successfully launched by ISRO’s Polar Satellite Launch Vehicle (PSLV-C57) from the Satish Dhawan Space Centre (SDSC), Sriharikota.
The Aditya-L1 spacecraft was successfully injected into an elliptical orbit of 235×19500 km around the planet after a flight length of 63 minutes and 20 seconds on that particular day.
A spacecraft positioned in a halo orbit around the L1 point, according to ISRO, has the significant benefit of continually seeing the Sun without any occultation or eclipses. This will provide us a better opportunity to watch the solar activity and how it affects the space weather in real time.
Aditya-L1 is carrying seven scientific payloads that were produced domestically by ISRO and national research organisations, including as the Inter University Centre for Astronomy and Astrophysics (IUCAA) in Pune and the Indian Institute of Astrophysics (IIA) in Bengaluru.
The payloads will use electromagnetic, particle, and magnetic field detectors to study the photosphere, chromosphere, and the Sun’s outermost layers (the corona).
Four payloads use the unique vantage point L1 to observe the Sun directly, while the remaining three payloads conduct in-situ particle and field investigations at the Lagrange point L1. This allows for significant scientific research on the propagation of solar dynamics in the interplanetary medium.
The most important data to comprehend the issue of coronal heating, coronal mass ejection, pre-flare and flare activities and their features, dynamics of space weather, and particle and field propagation is anticipated to be provided by the Aditya L1 payloads.
A tiny object prefers to stay at one of five Lagrangian points (or parking zones) between the Earth and the Sun, according to experts. The Italian-French mathematician Joseph-Louis Lagrange is honoured with the name of the Lagrange Points for his prize-winning article, “Essai sur le Problème des Trois Corps, 1772.”
Spacecraft can use these locations in space to stay there for longer periods of time while using less fuel. The gravitational attraction of the sun and the earth, which are at a Lagrange point, equals the centripetal force required for a tiny object to move with them.