Aditya L1 in orbit close to Lagrange Point 1. Timeline of India's solar mission

The instruments aboard Aditya-L1 are precisely calibrated to scrutinise the solar atmosphere, particularly the chromosphere and corona.

Aditya L1, India's first solar observatory, has successfully entered its designated orbit close to Lagrange point L1 on Saturday. From this vantage point, the spacecraft aims to gather crucial data to unravel the sequence of events leading to solar eruptions, contributing significantly to our understanding of space weather dynamics.

Aditya L1 on Saturday successfully parked at orbit around Lagrange Point 1 to study Sun.

The instruments aboard Aditya-L1 are precisely caliberated to scrutinise the solar atmosphere, particularly the chromosphere and corona, according to Indian Space Research Organisation (ISRO). Additionally, in-situ instruments will monitor the immediate environment at L1. Among the seven payloads onboard, four are dedicated to remote sensing of the Sun, while the remaining three focus on in-situ observations.

The seven payloads that Aditya L1 is carrying include:

1. Visible Emission Line Coronagraph(VELC): For observations od solar corona in three modes – Imaging, Spectroscopy and Spectropolarimetry.
2. Solar Ultraviolet Imaging Telescope (SUIT): It uses Narrow-Band (NB) and Broad-Band (BB) spectral filters to study the Sun-climate relations atmospheric dynamics of the Earth.
3. Solar Low Energy X-ray Spectrometer (SoLEXS): It uses soft x-ray sun-as-a-star spectrometer to directly investigate solar corona.
4. High Energy L1 Orbiting X-ray Spectrometer(HEL1OS): It is a hard X-ray sun-as-a-star spectometer that aims to study the phenomena occurring during solar flares.
5. Aditya Solar wind Particle Experiment(ASPEX): It will use low and high energy particle spectrometers to measure solar wind particles at first Sun-Earth Lagrange point, L1.
6. Plasma Analyser Package For Aditya (PAPA): It aims to study the composition of solar wind and its energy distributions.
7. Advanced Tri-axial High Resolution Digital Magnetometers: To measure the magnitude and direction of the Interplanetary Magnetic Field (IMFs) locally, and to study Coronal Mass Ejections (CMEs)

Here's a brief timeline of India's first solar mission

September 2, 2023: India's pioneering solar observatory embarks on its journey towards the Sun-Earth L1 point. The satellite is positioned precisely in its intended orbit following a successful launch by PSLV-C57.

September 3: The first Earth-bound manoeuvre is executed flawlessly from ISTRAC, Bengaluru, altering the orbit to 245 km x 22459 km. The satellite is in optimal condition and functioning as expected.

September 5: The second Earth-bound manoeuvre succeeds, modifying the orbit to 282 km x 40225 km.

September 10: The third Earth-bound manoeuvre is completed successfully, adjusting the orbit to 296 km x 71767 km.

September 15: The fourth Earth-bound manoeuvre accomplishes the target orbit of 256 km x 121973 km.

September 18: Aditya-L1 initiates the collection of scientific data.

September 30: The spacecraft exits Earth's sphere of influence and proceeds towards the Sun-Earth Lagrange Point 1 (L1).

October 6: A planned Trajectory Correction Manoeuvre (TCM), lasting approximately 16 seconds, corrects the spacecraft's trajectory post the Trans-Lagrangean Point 1 Insertion (TL1I) manoeuvre on September 19, 2023. The TCM ensures alignment with the intended path for the Halo orbit insertion around L1.

November 7: HEL1OS payload captures its first High-Energy X-ray glimpse of Solar Flares.

December 1: The Solar wind Ion Spectrometer (SWIS) within the Aditya Solar wind Particle Experiment (ASPEX) payload becomes operational.

December 10: The SUIT payload successfully captures full-disk images of the Sun in near ultraviolet wavelengths.

January 6, 2024: Aditya-L1, the solar observatory, achieves successful insertion into the Halo-Orbit around Sun-Earth L1, initiating the data collection essential for analysing the solar environment.

Major objectives of Aditya-L1 mission:

-Study the dynamics of the upper solar atmosphere, specifically the chromosphere and corona.

-Examine the mechanisms behind the heating of the chromosphere and corona, study the physics of partially ionised plasma, and explore the initiation of coronal mass ejections and solar flares.

-Observation of the in-situ particle and plasma environment to gather data crucial for understanding particle dynamics originating from the Sun.

-Explore the physics involved in heating the solar corona and understand its mechanisms.

-Analyse the plasma in the coronal and coronal loops, focusing on temperature, velocity, and density.

-Research into the development, dynamics, and origins of Coronal Mass Ejections (CMEs).

-Identify the sequential processes occurring across various solar layers (chromosphere, base, and extended corona) that contribute to solar eruptive events.

-Study the magnetic field topology and measurements in the solar corona.

-Examine the drivers behind space weather, including the origin, composition, and dynamics of solar wind.