After making history and successfully soft landing the Vikram lander of Chandrayaan 3 on the lunar surface, all eyes has been on the Indian Space Research Organisation (ISRO) to know more details about their mission to observe the Sun.
What is Aditya-L1, India’s mission to the Sun?
Aditya-L1 is a satellite intended for in-depth research on the Sun. It contains 7 different payloads that were all created locally. Five by ISRO and two by Indian academic institutes in collaboration with ISRO. Aditya in Sanskrit means the Sun. Lagrange Point 1 of the Sun-Earth system is referred to as L1 here.
It is the first Indian mission dedicated to observing the Sun. Nigar Shaji is the project’s director. It was launched aboard a PSLV-XL launch vehicle on 2 September 2023, ten days after the successful landing of ISRO’s moon mission, Chandrayaan 3. It successfully achieved its intended orbit nearly an hour later, and separated from the fourth stage.
Aditya L1 mission operates on a more modest budget of about Rs 400 Crore ($48 million)
What will Aditya-L1 do?
Aditya-L1’s primary scientific objectives encompass a wide range of critical aspects related to the Sun and its influence on our solar system. One of its key missions is to closely observe the dynamic behaviors occurring within the Sun’s chromosphere and corona, shedding light on the intricate processes of heating, plasma physics in partially ionised states, the origin of coronal mass ejections (CMEs), and the underlying mechanisms behind the transfer of heat and energy within the corona, as well as the exchange of solar flares.
Additionally, the satellite aims to comprehensively investigate the physical particle environment surrounding its orbital position, contributing to our understanding of solar particle interactions. Furthermore, Aditya-L1 seeks to unravel the sequence of processes unfolding in the multiple layers beneath the corona that culminate in solar eruptions, offering valuable insights into the drivers of space weather. Lastly, the mission aspires to explore the origin, composition, dynamics, and behavior of the solar wind, providing essential data for advancing our knowledge of the Sun’s impact on the broader solar system.
How will Aditya-L1 stay in space and observe the Sun?
For common understanding, L1 is a location in space where the gravitational forces of two celestial bodies, such as the Sun and Earth, are in equilibrium. This allows an object placed there to remain relatively stable with respect to both celestial bodies.
Aditya-L1 will stay in Earth-bound orbits for 16 days, during which it will undergo 5 maneuvres to gain the necessary velocity for its journey. Subsequently, Aditya-L1 undergoes a Trans-Lagrangian1 insertion manoeuvre, marking the beginning of its 110-day trajectory to the destination around the L1 Lagrange point. Upon arrival at the L1 point, another manoeuvre binds Aditya-L1 to an orbit around L1, a balanced gravitational location between the Earth and the Sun. The satellite spends its whole mission life orbiting around L1 in an irregularly shaped orbit in a plane roughly perpendicular to the line joining the Earth and the Sun.
The strategic placement at the L1 Lagrange point ensures that Aditya-L1 can maintain a constant, uninterrupted view of the Sun. This location also allows the satellite to access solar radiation and magnetic storms before they are influenced by Earth’s magnetic field and atmosphere. Additionally, the L1 point’s gravitational stability minimises the need for frequent orbital maintenance efforts, optimising the satellite’s operational efficiency.
Fun fact about Aditya-L1
Aditya-L1 will stay approximately 1.5 million km away from Earth, directed towards the Sun, which is about 1% of the Earth-Sun distance.
