Aditya-L1 Mission: India’s First Solar Observatory, Objectives and Key Facts

Aditya-L1 Enters Sun’s Final Orbit

ISRO achieved another milestone on January 6, 2024, by successfully executing the last manoeuvre to position the Aditya-L1 spacecraft into its designated orbit, marking India’s accomplishment in deploying its inaugural solar observatory. This observatory, designed to study the Sun, has now reached its final destination approximately 1.5 million kilometres away from Earth. India celebrates the successful establishment of Aditya-L1, reinforcing its capabilities in space exploration.

Aditya L1 Mission Launch Date and Time

For further information about the Aditya L1 Solar Mission Details, see the Points below. You should be aware that this is ISRO’s first solar mission, and that it will be launched on September 2, 2023. Check the details on ISRO Aditya L1 Mission Launch Date below in the table:

Launch Vehicle of Aditya L1 Mission

The Aditya L1 Solar Mission was launched by the Indian Space & Research Organisation on September 2, 2023. The spacecraft is transported by PSLV-XL, the Aditya L1 Launch Vehicle. Aditya L1 will split from the spacecraft after the launch vehicle has sent it into orbit. After the launch of Chandrayaan 3, ISRO’s Aditya L-1 mission is the organisation’s second straight mission.

Payloads of Aditya L1 Mission

• Visible Emission Line Coronagraph (VELC): VELC is the prime payload designed as a reflective coronagraph with a multi-slit spectrograph.
• Solar Low Energy X-ray Spectrometer (SoLEXS): SoLEXS is a soft X-ray spectrometer designed to measure the solar soft X-ray flux to study solar flares.
• Plasma Analyser Package for Aditya (PAPA): PAPA is designed to understand solar winds and their composition and perform mass analysis of solar wind ions.
• High Energy L1 Orbiting X-Ray Spectrometer (HEL1OS): HEL1OS is a hard X-Ray spectrometer designed to study solar flares in the high-energy X-rays.
• Solar Ultra-violet Imaging Telescope (SUIT): SUIT is a UV telescope to image the solar disk in the near UV wavelength range.
• Aditya Solar wind Particle EXperiment (ASPEX): ASPEX payload comprises 2 sub-systems: SWIS & STEPS.
  • Solar Wind Ion Spectrometer (SWIS) is a low-energy spectrometer designed to measure the proton and alpha particles of the solar wind.
  • Supra-Thermal & Energetic Particle Spectrometer (STEPS) is a high-energy spectrometer designed to measure high-energy ions of the solar wind.
• Magnetometer: MAG will measure the low-intensity interplanetary magnetic field in space. It has two steps of Magnetic sensors.

Complete Details of Aditya-L1 Mission

Aditya L1 Mission is the first space-based observatory-class Indian solar mission to study the Sun. The spacecraft is planned to be placed in a halo orbit around the Lagrange Point 1 (L1) of the Sun-Earth system, which is about 1.5 million km from the Earth. A satellite placed in the halo orbit around the L1 point has the major advantage of continuously viewing the Sun without any occultation/eclipse.

This will provide a greater advantage in observing solar activities continuously. The spacecraft carries seven payloads to observe the photosphere, chromosphere, and the outermost layers of the Sun (the corona) using electromagnetic and particle detectors. Using the special vantage point of L1, four payloads directly view the Sun, and the remaining three payloads carry out in-situ studies of particles and fields at the Lagrange point L1.

The suite of Aditya L1 Mission payloads is expected to provide the most crucial information to understand the problems of coronal heating, Coronal Mass Ejection, pre-flare and flare activities, and their characteristics, dynamics of space weather, study of the propagation of particles, and fields in the interplanetary medium, etc.

Aditya L1 Solar Mission Uniqueness

• First time spatially resolved solar disk in the near UV band.
• CME dynamics close to the solar disk (~ from 1.05 solar radius), thereby providing information on the acceleration regime of CME, which is not observed consistently.
• On-board intelligence to detect CMEs and solar flares for optimised observations and data volume.
• Directional and energy anisotropy of solar wind using multi-directional observations.

Details of Aditya L1 Mission Payloads

The Aditya-L1 mission carries a suite of seven scientific payloads to carry out a systematic study of the Sun. All the payloads are developed with the close collaboration of various centres of the Indian Space Research Organization (ISRO). All seven Aditya L1 Mission Payloads have been discussed below:

Visible Emission Line Coronagraph (VELC)

The Visible Emission Line Coronagraph (VELC) studies the solar corona and dynamics of Coronal Mass Ejections. The VELC instrument was developed at the Indian Institute of Astrophysics, Bangalore.

Solar Ultra-violet Imaging Telescope

The Solar Ultra-violet Imaging Telescope (SUIT) payload images the Solar Photosphere and Chromosphere in near Ultra-violet (UV) and also measures the solar irradiance variations in near UV. The SUIT instrument at the Inter-University Centre for Astronomy & Astrophysics, Pune.

Aditya Solar Wind Particle Experiment & Plasma Analyser Package for Aditya

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 their energy distribution. The ASPEX instrument at the Physical Research Laboratory, Ahmedabad, the PAPA payload at Space Physics Laboratory, Vikram Sarabhai Space Centre, Thiruvananthapuram

Solar Low Energy X-ray Spectrometer & High Energy L1 Orbiting X-ray Spectrometer

The Solar Energy X-ray Spectrometer (SoLEXS) 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 SoLEXS and HEL1OS payloads at U R Rao Satellite Centre, Bangalore.

Magnetometer

The Magnetometer payload is capable of measuring interplanetary magnetic fields at the L1 point. The Magnetometer payload at the Laboratory for Electro-Optics Systems, Bangalore.

Where will the Aditya L1 be placed?

Aditya L1 spacecraft would originally be sent into low-Earth orbit (LEO). With the use of onboard propulsion, the spacecraft’s orbit will then be made more elliptical, and it will be launched towards the Lagrange Point L1 between the Sun and the Earth system.

The spaceship will leave the gravitational Sphere of Influence (SOI) of the Earth as it moves toward L1. The Sun-Earth Lagrange Point L1 will thereafter be the object of Aditya L1’s final orbit, which will be a wide halo orbit. This location in space is 1.5 million kilometres away from Earth. The gravitational pulls of the Sun and Earth are balanced at the L1 point, which is a stable place.

Why is Aditya L1 placed at the L1 point between Sun and Earth?

In layman’s terms, the Aditya L1 spacecraft will be put in the vast halo orbit around the Sun-Earth Lagrange Point L1, which will help to ensure that there are no occultations or eclipses that prevent a continuous view of the Sun. Let’s examine the Lagrange Points to provide a scientific explanation.

Lagrange Points

For a two-body gravitational system, the Lagrange Points are the positions in space where a small object tends to stay if put there. These points in space for a two-body system, such as the Sun and Earth, can be used by spacecraft to remain at these positions with reduced fuel consumption.

Technically, at the Lagrange point, the gravitational pull of the two large bodies equals the necessary centripetal force required for a small object to move with them. For two-body gravitational systems, there is a total of five Lagrange points denoted as L1, L2, L3, L4 and L5. The Lagrange points for the Sun-Earth system are shown in the figure. The Lagrange point L1 lies between the Sun-Earth line. The distance of L1 from Earth is approximately 1% of the Earth-Sun distance.

Benefits of Aditya L1 Solar Mission

• The spacecraft will have the advantage of continuously observing the Sun without any occultation or eclipse, thanks to its positioning in the unique vantage point of L1.
• This will enable us to comprehend the Sun and how it affects Earth better.
• The information acquired from the mission will help us better understand and predict space weather phenomena like solar flares, CMEs, solar wind, and other phenomena that have an impact on the operation of space technology near or on Earth, as well as other planets.
• When it comes to the Earth, a magnetic disturbance can occur when the Earth’s magnetic field interacts with the field delivered by the CME.
• Space weather events have the potential to significantly affect our satellites, communication networks, and power grids. We can better safeguard ourselves from these occurrences by comprehending the Sun.

Aditya L1 Launch Budget

The orbit of Aditya-L1 will be set in the Sun-Earth system’s L1, where the gravitational pull of both bodies is balanced out. For the Aditya-L1 mission in 2019, the Centre approved funding equivalent to around $46 million. Costs have not received an official update from the ISRO.

Aditya L1, a flagship project of ISRO, has a substantial budget in line with its complexity and significance. The budgeted amount will go toward designing, developing, launching, and operating spacecraft. The budget includes all research, development, and testing phases as well as the high-end equipment and expertise required for investigating the Sun’s corona.

The estimated 400 Crore budget includes funds for post-launch activities, operational costs, and contingencies. With this expenditure, India is demonstrating its dedication to enhancing its space capabilities and boosting global science.

Aditya-L1 Mission to use PSLV-C57 rocket for launch

The mission will launch with a PSLV-C57 rocket. Aditya-L1 is equipped with seven specialised payloads that can observe the photosphere, chromosphere, and corona of the Sun at various wavelengths. Earlier on August 14, ISRO provided an update on the preparations for the launch of mission Aditya-L1, the first Indian observatory to study the Sun from orbit.

Aditya-L1, the first Indian observatory to study the Sun from orbit, is getting ready for launch as part of the PSLV-C57 mission. The U R Rao Satellite Centre (URSC), Bengaluru-built satellite, has arrived at SDSC-SHAR, Sriharikota.

Other Solar Missions

Sharing is caring!