Aditya L-1: ISRO targets September 15 for cruicial earth-bound manoeuvre

Aditya L-1 will initiate a Trans-Lagrangian-1 Insertion (TL-I) manoeuvre

Aditya-L1 selfie VELC and SUIT payloads as seen by Aditya-L1 camera

On September 10, ISRO Telemetry Tracking and Command Network (ISTRAC) executed the third Earth-bound manoeuvre for Aditya L-1. This mission represents India’s inaugural solar space observatory, which was launched on September 2, 2023. ISRO noted that the manoeuvre took place at 2.30 a.m. and the satellite was tracked during this operation by ground stations located in Mauritius, Bengaluru, SDSC-SHAR (Sriharikota) and Port Blair in the Andamans. 

Now looking ahead, on September 15, Aditya L-1 will undergo two additional manoeuvres to attain the required velocity for its journey to reach L-1. After concluding its manoeuvres within Earth’s orbit, which will take place on the 16th day following the launch, Aditya L-1 will initiate a Trans-Lagrangian-1 Insertion (TL-I) manoeuvre, commencing its 110-day journey toward the L-1 position. 

L-1, situated approximately 1.5 million kilometres from Earth, designates Lagrange Point-1 within the Sun-Earth system. It represents a region in space where the gravitational forces exerted by two celestial bodies, like the Sun and Earth, balance each other. This unique equilibrium enables an object positioned at L-1 to maintain relative stability in relation to both celestial bodies. 

“Upon reaching the L-1 point, Aditya L-1 will execute an additional manoeuvre to establish itself in an orbit around L-1. Throughout its mission duration, the satellite will continue to orbit L-1, following an irregularly shaped orbit situated in a plane that is approximately perpendicular to the line connecting Earth and the Sun. This orbit is called the ‘Halo Orbit' remarked space expert Girish Linganna. 

The mission’s goals encompass gaining comprehensive insights into the Sun’s chromospheric and coronal heating, as well as the behaviour of partially ionized plasma. It aims to investigate such phenomena as the formation of coronal mass ejections and solar flares. With seven distinct payloads, the mission is engineered to explore various layers of the Sun, including the outermost layer, providing real-time data on the coronal layer. Additionally, the mission will delve into the creation and composition of solar wind and space weather. The ISRO satellite also intends to issue warnings when solar winds change direction, heading towards Earth at speeds exceeding 600 km/sec. 

Last week the Aditya L-1 captured remarkable images during its orbit around Earth and ISRO has shared these as the first snapshots taken by Aditya L-1. ISRO mentioned, “Aditya L-1, on its way to the Sun-Earth L-1 point, has taken self-portraits along with images of the Earth and the Moon.” 

“In the self-portrait, two significant scientific instruments, the Visible Emission Line Coronagraph (VELC) for Corona imaging and spectroscopy research and the Solar Ultraviolet Imaging Telescope (SUIT) for Photosphere and Chromosphere imaging in narrow and broadband can be observed. In the second image, the onboard camera provides a close-up view of Earth and a more distant view of the Moon,” said Linganna. 

Before that, Aditya L-1 also performed many earth-bound manoeuvres such as the first manoeuvre on September 3, 2023, at 11.40 am (IST). The new orbit attained was 245 km (periapsis) x 22,459 km (apoapsis) and the second manoeuvre was on September 5, 2023, at 03.00 am (IST). The new orbit attained was 282 km x 40,225 km and the third manoeuvre was on September 10, 2023, at 2.30 a.m. (IST). The new orbit attained was 296 km x 71,767 km. Now the fourth manoeuvre is scheduled for September 15, 2023, at 02.00 a.m. (IST).