- Aditya-L1is the first space based observatory class Indian solar mission to study the Sun from a substantial distance of5 million kilometers. It will take approximately 125 days to reach the L1 point.
- Aditya-L1 is also ISRO’s second astronomy observatory-class mission after AstroSat (2015).
- The mission’s journey is notably shorter than India’s previous Mars orbiter mission, Mangalyaan.
- The spacecraft is planned to be placed in a halo orbitaround the Lagrangian point 1 (L1) of the Sun-Earth system.
- Indian Space Research Organisation (ISRO) successfully launched Aditya-L1, India’s first solar mission, from Satish Dhawan Space Centre in Andhra Pradesh’s Sriharikota on September 2, 2023.
- Aditya-L1 shall be the first space-based Indian observatory 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.
- The successful launch of India’s first solar mission came a week after the historic landing of Chandrayaan-3 on the south pole of the lunar surface.
- The Aditya-L1 mission carries a suite of seven scientific payloads to carry out systematic study of the photosphere, chromosphere and the outermost layers of the Sun (the corona) using electromagnetic and particle and magnetic field detectors:
- Visible Emission Line Coronagraph (VELC): shall study the solar corona and dynamics of Coronal Mass Ejections.
- Solar Ultraviolet Imaging Telescope (SUIT): payload shall image the Solar Photosphere and Chromosphere in near Ultraviolet (UV) and also measure the solar irradiance variations in near UV.
- Aditya Solar wind Particle EXperiment (ASPEX) and Plasma Analyser Package for Aditya (PAPA): payloads shall study the solar wind and energetic ions, as well as their energy distribution.
- The Solar Low Energy X-ray Spectrometer (SoLEXS) and The High Energy L1 Orbiting X-ray Spectrometer (HEL1OS): shall study the X-ray flares from the Sun over a wide X-ray energy range.
- Magnetometer payload: is capable of measuring interplanetary magnetic fields at the L1 point.
- Using the special vantage point L1, four payloads shall directly view the Sun and the remaining three payloads shall carry out in-situ studies of particles and fields at the L1, thus providing important scientific studies of the propagatory effect of solar dynamics in the interplanetary medium.
- The mission aims to provide valuable insights into the solar corona, photosphere, chromosphere, and solar wind.
- The primary objective of Aditya-L1 is to gain a deeper understanding of the Sun’s behavior, including its radiation, heat, particle flow, and magnetic fields, and how they impact Earth.
Why study the Sun?
- The Sun is the nearest star and therefore can be studied in much more detail as compared to other stars. By studying the Sun, the Indian space agency envisages to learn much more about stars in our Milky Way as well as about stars in various other galaxies.
- The Sun is a very dynamic star that shows several eruptive phenomena and releases immense amounts of energy in the solar system. ISRO states that if such explosive solar phenomenon is directed towards the earth, it could cause various types of disturbances in the near earth space environment.
- Various spacecraft and communication systems are prone to such disturbances and therefore an early warning of such events is important for taking corrective measures beforehand. In addition to these, if an astronaut is directly exposed to such explosive phenomena, he/she would be in danger. The various thermal and magnetic phenomena on the Sun are of extreme nature. Thus, the Sun also provides a good natural laboratory to understand those phenomena which cannot be directly studied in the lab.
What is the Significance of Exploring the Sun?
Understanding Our Solar System
- The Sun is the center of our solar system,and its characteristics greatly influence the behavior of all other celestial bodies.
- Studying the Sun enhances our understanding of the dynamics of our solar neighborhood.
Space Weather Prediction
- Solar activities, such as solar flaresand coronal mass ejections, can impact Earth’s space environment.
- Understanding these phenomena is crucial forpredicting and mitigating potential disruptions to communication systems, navigation, and power grids.
Advancing Solar Physics
- Exploring the Sun’s complex behavior, including its magnetic fields,heating mechanisms and plasma dynamics, contributes to advances in fundamental physics and astrophysics.
Enhancing Energy Research
- The Sun is a natural fusion reactor.Insights gained from studying its core and nuclear reactions can inform our pursuit of clean and sustainable fusion energy on Earth.
Improving Satellite Operations
- Solar radiation and solar wind affect the functioning of satellites and spacecraft.
- Understanding these solar interactions allows for better spacecraft design and operation.
What are Lagrange Points?
- Lagrange pointsare special positions in space where the gravitational forces of two large orbiting bodies, such as the Sun and the Earth, balance each other out.
- This means that a small object, such as aspacecraft, can stay at these points without using much fuel to maintain its orbit.
- There arefive Lagrange Points, each with distinct characteristics. These points enable a small mass to orbit in a stable pattern amid two larger masses.
- Lagrange Points in the Sun-Earth System:
- L1: is considered the most significant of the Lagrange points for solar observations. A satellite placed in the halo orbit around the L1 has the major advantage of continuously viewing the Sunwithout any occultation/ eclipses. It is currently home to the Solar and Heliospheric Observatory Satellite (SOHO).
- L2: Positioned directly ‘behind’ Earth as viewed from the Sun, L2 is excellent for observing the larger Universe without Earth’s shadow interference. The James Webb Space Telescopeorbits the Sun near L2.
- L3: Positioned behind the Sun, opposite Earth, and just beyond Earth’s orbit, it offerspotential observations of the far side of the Sun.
- L4 and L5: Objects at L4 and L5 maintain stable positions, forming an equilateral triangle with the two larger bodies. They are often used for space observatories, such as those studying asteroids.
Other Solar Missions by Different Countries
- Parker Solar Probe (August 2018):Touched the Sun’s upper atmosphere, sampled particles and magnetic fields in December 2021.
- Solar Orbiter (February 2020): Explores the Sun’s changing space environment.
- Hinotori (ASTRO-A, 1981):Studied solar flares using hard X-rays
- Yohkoh (SOLAR-A, 1991):Studied solar activity
- Hinode (SOLAR-B, 2006):Studied the Sun’s impact on Earth.
- Ulysses (October 1990):Studied space environment above and below the Sun’s poles
- Proba-2 (October 2001):Part of solar exploratory missions.
- Upcoming:Proba-3 (2024), Smile (2025)
- Advanced Space-based Solar Observatory (ASO-S, October 2022):Launched to observe the Sun.
- The Aditya-L1 mission by ISRO holds significant importance for India due to its focus on studying the Sun and the solar corona. This mission aims to achieve the following:
- Scientific Understanding:The mission’s primary objective is to deepen our understanding of the Sun, its radiation, magnetic fields, and the flow of particles.
- Space Weather Forecasting:By studying the Sun’s behaviour, the mission can contribute to predicting space weather events, such as solar flares, that can disrupt satellite communications and other technologies on Earth.
- Technological Advancement:Developing a space-based observatory to study the Sun demonstrates India’s technological prowess in space exploration and adds to its reputation in the global space community.
- International Collaboration:Participating in solar research aligns with international efforts to understand the Sun and its effects.
- Education and Inspiration:The mission inspires future scientists, engineers, and researchers by showcasing India’s achievements in space science and encouraging the pursuit of space-related careers.
- Data for Innovation:The collected data can lead to innovations in technology, materials science, and various other fields that can benefit India’s technological landscape.
The Aditya L1 Mission is an ambitious project by the ISRO. Its success is much awaited as it will add another feather to India’s cap and its great contributions to space technology.