ISRO to launch its first solar mission Aditya-L1 to study Sun. What is it?
Aditya-L1 is planned to be placed in a halo orbit around the Lagrange point 1 (L1), around 1.5 million km from the Earth, of the Sun-Earth system.
Aditya-L1, which will be the first space-based Indian mission to study the Sun, is getting ready for launch, the Indian Space Research Organisation (ISRO) said on Monday.
Taking to X, formerly known as Twitter, the ISRO said, “Aditya-L1, the first space-based Indian observatory to study the Sun, is getting ready for the launch. The satellite realised at the U R Rao Satellite Centre (URSC), Bengaluru has arrived at SDSC-SHAR, Sriharikota.”
What is the Aditya L1 mission?
The Aditya L1 mission will be the first space-based observatory Indian solar mission to study the Sun, the ISRO said. The spacecraft is planned to be placed in a halo orbit around the Lagrange point 1 (L1), around 1.5 million km from the Earth, of the Sun-Earth system.
As per the ISRO, the mission will be launched by PSLV rocket from the Sathish Dhawan Space Centre SHAR (SDSC SHAR) in Sriharikota. While the spacecraft will initially be placed in a low earth orbit. Further, as the orbit is made more elliptical, the spacecraft will then be launched towards the L1 point by using an on-board propulsion.
The ISRO said as the spacecraft moves towards L1, it will exit the Earth's gravitational Sphere of Influence (SOI), after which the cruise phase will begin. The spacecraft will then be injected into a huge halo orbit around L1.
The total time of travel from the launch to the L1 point would take around four months for Aditya-L1.
According to the ISRO, a satellite which will be placed around the L1 will have a significant advantage of continuously having the Sun's view without being obstructed by any occultation or eclipses.
The mission will also provide another advantage of observing solar activities and witnessing their impact on space weather in real-time.
The spacecraft will be carrying seven payloads in order to observe the photosphere, chromosphere and the topmost layers of the Sun (the corona) by using electromagnetic and particle and magnetic field detectors.
It will use the L1 special vantage point to directly view the sun with four payloads and three payloads will study the particles and fields at the L1 point, “thus providing important scientific studies of the propagatory effect of solar dynamics in the interplanetary medium”, ISRO's website states.
Aditya L1 payloads are expected to deliver crucial information related to problems of coronal heating, coronal mass ejection, pre-flare and flare activities and their characteristics, dynamics of space weather, propagation of particles and fields, among other things.
What are the major objectives of the mission?
The mission will focus on study of the Solar upper atmospheric (chromosphere and corona) dynamics. It will also study the chromospheric and coronal heating, physics of the partially ionized plasma, initiation of the coronal mass ejections, and flares.
The mission will observe the particle and plasma environment which will be providing the data for the study of particle dynamics from the Sun. The mission will also focus on understanding the physics of solar corona and its heating mechanism.
It will dive deeper into the temperature, velocity and density of coronal and coronal loops plasma. It will also research the development, dynamics and origin of CMEs.
The mission will identify the chronology of processes that take place in Sun's multiple layers — chromosphere, base and extended corona — which often eventually leads to solar eruptive events.
In the solar corona, the mission aims to find out the magnetic field topology and measurements.
It will also identify what drives space weather, along with the origin, composition and dynamics of the solar wind.
As per ISRO, “The instruments of Aditya-L1 are tuned to observe the solar atmosphere mainly the chromosphere and corona. In-situ instruments will observe the local environment at L1. There are a total of seven payloads on-board with four of them carrying out remote sensing of the Sun and three of them carrying in-situ observation.”
What are the seven payloads?
The Aditya-L1 mission will be carrying seven scientific payloads to “carry out systematic study of the Sun”.
The payloads are:
The Visible Emission Line Coronagraph (VELC) will study the Corona, imaging and spectroscopy, and Coronal mass ejections.
The Solar Ultraviolet Imaging Telescope (SUIT) will focus upon the Photosphere and Chromosphere imaging- narrow and broadband. It will also measure the solar irradiance variations. t
The Solar Low Energy X-ray Spectrometer (SoLEXS) and High Energy L1 Orbiting X-ray Spectrometer (HEL1OS) will study the soft and hard X-ray flares form the Sun over wide X-ray energy range.
The Aditya Solar wind Particle Experiment (ASPEX) and Plasma Analyser Package For Aditya (PAPA) will analyse the electrons and protons in the Solar wind or particles. It will also study the energetic ions.
The Advanced Tri-axial High Resolution Digital Magnetometers will study the interplanetary magnetic field at L1 point.