Article Posted on : - Sep 04, 2023

Indian Space Research Organisation's (ISRO) Aditya-L1, India's maiden solar mission, on board PSLV-C57 lifts off from the launch pad at Satish Dhawan Space Centre, in Sriharikota on Saturday, Sept. 2, 2023. (A PTI Photo)

SRIHARIKOTA (PTI): The Aditya-L1 spacecraft onboard a PSLV rocket on Saturday successfully got separated and would be proceeding on its journey towards the Sun on a 125-day voyage , ISRO said on Saturday.

ISRO chief S Somanath said the spacecraft was injected in the "precise orbit".

"Aditya L1 spacecraft has been injected in an elliptical orbit of 235 by 19,500 km which is intended, very precisely by the PSLV," he said.

"From now on Aditya L1 will go on a long journey for 125 days," towards the Sun, he said from the Mission Control Center in Sriharikota, flanked by Union Minister Jitendra Singh, Project Director Nigar Shaji and Mission Director Biju.

Shaji said the spacecraft was injected into the orbit flawlessly by the PSLV "as always," and that the solar panels are deployed. "Aditya L1 has started 125 days of long journey to the Sun," she said.

Union Minister Singh described the achievement as a "Sunshine Moment," and thanked Prime Minister Narendra Modi for the support to the space sector.

The Sun is a giant sphere of gas and Aditya-L1 would study its outer atmosphere. Aditya-L1 will neither land on the Sun nor approach it any closer, ISRO said.

It is expected to travel for about 125 days to reach the Halo orbit around the Lagrangian Point L1, which is considered closest to the Sun.

Aditya-L1, weighing about 1,480.7 kg, is the first space-based observatory class to study the Sun.

The objectives of Aditya-L1 mission includes study of coronal heating, solar wind acceleration, Coronal Mass Ejections (CME), dynamics of solar atmosphere and temperature anisotropy.

Following Saturday's launch, the Aditya-L1 stays in Earth-bound orbits for 16 days, during which it undergoes five maneuvers to gain the necessary velocity for its journey towards the Sun.

Subsequently, the spacecraft undergoes a Trans-Lagrangian 1 insertion manoeuvre, marking the beginning of its 110-day trajectory to the destination around its destination.

Upon arrival at the L1, another manoeuvre binds Aditya-L1 to an orbit around the point, which is a balanced gravitational location between the Earth and the Sun.

The spacecraft spends its whole mission life of five years orbiting around L1 in an irregularly shaped orbit in a plane roughly perpendicular to the line joining the Earth and the Sun, ISRO said.

The strategic placement at the L1 Lagrange point ensures the spacecraft 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, the space agency informed.

Additionally, the L1 point's gravitational stability minimises the need for frequent orbital maintenance efforts, optimising the spacecraft's operational efficiency.

Aditya-L1 will stay approximately 1.5 million km away from the Earth, directed towards the Sun, which is about 1 per cent of the Earth-Sun distance.

The PSLV C57 is the 59th flight of the launch vehicle, a trusted workhorses of ISRO and is the 25th mission using PSLV-XL configuration, ISRO said.

The atmosphere of the Earth as well as its magnetic field act as protective shield and block harmful wavelength radiations. In order to detect such radiation, solar studies are carried out from space.

Aditya-L1 mission carries seven scientific payloads to carry out the study.

The Visible Emission Line Coronagraph, which studies the solar corona and dynamics of Coronal Mass Ejections (CME), will be sending 1,440 images per day to the ground station for analysis on reaching the intended orbit.

The Solar Ultraviolet Imaging Telescope payload images the Solar photosphere and Chromosphere in near Ultraviolet and also measures the solar irradiance variations.

The Aditya Solar Wind Particle Experiment (ASPEX) and Plasma Analyser Package for Aditya (PAPA) payloads study the solar wind and energetic ions as well as the energy distribution.

The Solar Low Energy X-ray Spectrometer and the High Energy L1 Orbiting X-ray Spectrometer (HEL1OS) study the X-ray flares from the Sun over a wide X-ray energy range.

The Magnetometer payload is capable of measuring interplanetary magnetic fields at the L1 point.

The Science payloads of Aditya-L1 are indigenously developed with the close collaboration of various centers of ISRO.