ESA is playing a key role in India’s Aditya-L1 solar mission

“For the Aditya-L1 mission, we are providing support from all three of our 35-metre deep space antennas in Australia, Spain and Argentina, as well as support from our Kourou station in French Guiana and coordinated support from Goonhilly Earth Station in the UK.”

With these tools, ESA will offer deep space communication services to the mission. In 2022, the agency also assisted ISRO with the validation of its new flight dynamics software.

Aditya-L1 will be heading to the first Lagrange point, L1, situated between Earth and the Sun, roughly one percent of the distance to the Sun. This spot not only offers clear views of our star but also boasts the right gravitational forces and orbital motion to create a space where a spacecraft can function without having to use a lot of fuel. This is by definition the meaning of a Lagrange point.

However, L1 is a notoriously unstable location. In order for Aditya-L1 to reach this point and stay in orbit, agencies on Earth need to be kept aware of where exactly the spacecraft is and where it is heading.

A perfect position

To achieve this complicated goal, they use mathematical formulas and apply them to the tracking data from the spacecraft in order to properly track and evaluate its various locations. This process is known as ‘orbit determination’ and it's one that ESA helped ISRO with.

“With its experience flying and even rescuing missions at the Lagrange points, ESA was in the perfect position to help ISRO improve their new orbit determination software and demonstrate that it has the fidelity and accuracy that the organization needs in order to operate a spacecraft at a Lagrange point for the first time,” said ESA Flight Dynamics expert Frank Budnik.

Once the Aditya-L1 spacecraft is safely in orbit, it will use seven instruments to study our powerful Sun and answer crucial questions such as why the outer layers of the star remain hotter than its surface, and the origin and variation of solar flares.

Out of the seven tools, four will be placed to view the Sun directly, while three will undertake in-situ measurements.

The mission is a great illustration of the incredible things that can be achieved when international space organizations work together for the advancement and development of science initiatives. In the past,  ESA has worked with NASA’s Jet Propulsion Laboratory (JPL) on perfecting the interplanetary orbit determination software for ESA’s Mars Express mission and for the comet-hunting mission Rosetta.