- Mysteries of the Sun: ISRO’s ambitious Aditya-L1 mission will try and uncover the secrets behind the solar corona.
- This comprehensive solar and space environment observatory to be placed at the Lagrangian point
- The spacecraft carries seven payloads to observe the photosphere, chromosphere and the outermost layers of the Sun, the corona
Bangalore, June 17. The Indian Space Agency, Indian Space Research Organisation (ISRO), has announced big plans in the coming months to expand the scope of its activities above Earth’s atmosphere.
R Anil Kumar, India Strategic, takes a glimpse at what the Indian Space Agency has chalked out in the coming month’s, especially on its Maiden –Solar Mission – Aditya L1, where the Space Agency, ISRO, is taking a giant step to unveil secrets of the Sun.
From setting a date for Chandrayaan-3’s lift-off, ISRO Chief S Somanath announced a series of space programmes to cement India’s position in the International space fraternity.
But one ISRO project — which is as grand as Chandrayaan-3 and has a mission on the same lines as that of the Parker Solar Probe, of NASA, is India’s very own probe to study the Sun: the Aditya-L1.
Scheduled to be launched sometime in mid August this year, the Aditya-L1 mission was originally christened Aditya-1.
Aditya L1 shall be the first space based Indian mission to study the Sun. The spacecraft shall 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 or eclipses. This will provide a greater advantage of observing the solar activities and its effect on space weather in real time.
The spacecraft carries seven payloads to observe the photosphere, chromosphere and the outermost layers of the Sun (the corona) using electromagnetic and particle and magnetic field detectors.
Using the special vantage point 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, thus providing important scientific studies of the propagatory effect of solar dynamics in the interplanetary medium.
The suits of Aditya L1 payloads are expected to provide most crucial information to understand the problem of coronal heating, coronal mass ejection, pre-flare and flare activities and their characteristics, dynamics of space weather, propagation of particle and fields etc.
Science Objectives:
The major science objectives of Aditya-L1 mission are to Study the Solar upper atmospheric (chromosphere and corona) dynamics.
Study of chromospheric and coronal heating, physics of the partially ionized plasma, initiation of the coronal mass ejections, and flare, observe the in-situ particle and plasma environment providing data for the study of particle dynamics from the Sun.
Physics of solar corona and its heating mechanism, diagnostics of the coronal and coronal loops plasma: Temperature, velocity and density. Development, dynamics and origin of CMEs. Identify the sequence of processes that occur at multiple layers (chromosphere, base and extended corona) which eventually leads to solar eruptive events, Magnetic field topology and magnetic field measurements in the solar corona, drivers for space weather (origin, composition and dynamics of solar wind),study are also on the cards.
Aditya-L1 Payloads:
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 total seven payloads on-board with four of them carrying out remote sensing of the Sun and three of them carrying in-situ observation.
Visible Emission Line Coronagraph (VELC): The coronagraph creates an artificial total solar eclipse in space by blocking the sunlight by an occult. This telescope will have capabilities of spectral imaging of the corona in visible and infra-red wavelengths. To study the diagnostic parameters of solar corona and dynamics and origin of Coronal Mass Ejections (3 visible and 1 Infra-Red channels); magnetic field measurement of solar corona down to tens of Gauss – Indian Institute of Astrophysics (IIA)-Solar Ultraviolet Imaging Telescope (SUIT): The SUIT will observe the Sun between the 200-400 nm wavelength range and it will provide full disc images of the different layers of the solar atmosphere using 11 filters. The Sun has never been observed from space in this wavelength range. With the spacecraft being at the first Lagrangian point, the SUIT will observe the Sun continuously without interruption. The SUIT payload weighs nearly 35 kg- Inter-University Centre for Astronomy & Astrophysics (IUCAA)
Aditya Solar wind Particle Experiment (ASPEX): To study the variation of solar wind properties as well as its distribution and spectral characteristics – Physical Research Laboratory (PRL)
Plasma Analyser Package for Aditya (PAPA): To understand the composition of solar wind and its energy distribution – Space Physics Laboratory (SPL), VSSC
Solar Low Energy X-ray Spectrometer (SoLEXS) : To monitor the X-ray flares for studying the heating mechanism of the solar corona – ISRO Satellite Centre (ISAC)
High Energy L1 Orbiting X-ray Spectrometer (HEL1OS): To observe the dynamic events in the solar corona and provide an estimate of the energy used to accelerate the particles during the eruptive events – ISRO Satellite Centre (ISAC)and Udaipur Solar Observatory (USO), PRL
Magnetometer: To measure the magnitude and nature of the Interplanetary Magnetic Field– Laboratory for Electro-optic Systems (LEOS) and ISAC.
Importance:
Accurate knowledge of solar phenomena is important for understanding space weather.
To study the effects of variation in the solar weather system: changes in this weather can alter satellites’ orbits or shorten their lives, interfere with or damage on-board electronics, and cause power blackouts on earth etc.
The evolution of every planet, including Earth and exo-planets beyond the Solar System, is controlled by its parent star, the Sun in our case. Solar weather and the environment affect the weather of the entire system. Therefore it is necessary to study the Sun.
This project also provides an opportunity to solar scientists from multiple institutions within the country and the Scientific Fraternity the World over, to participate in space-based instrumentation and observations.
Thus, the enhanced Aditya-L1 project will enable a comprehensive understanding of the dynamical processes of the sun and address some of the outstanding problems in solar physics.
