The Indian Space Research Organisation (ISRO) has unveiled plans to launch the Aditya-L1 mission, a groundbreaking endeavor focused on studying the Sun from space. The announcement follows closely on the heels of the triumphant landing of ISRO’s Chandrayaan-3 lunar mission on the Moon’s surface.
Building upon the success of the AstroSat mission launched in 2015, Aditya-L1 will stand as ISRO’s second space-based astronomy initiative. Originally designated as Aditya 1, the mission has been rebranded as Aditya-L1, showcasing its primary objective of observing the solar corona.
Unlike its predecessor, AstroSat, which investigated celestial sources across X-ray, optical, and UV spectral bands simultaneously, Aditya-L1 will concentrate solely on the Sun, marking India’s pioneering foray into solar studies from space. The spacecraft is poised to be positioned within a halo orbit encircling the Lagrange point 1 (L1) within the Sun-Earth system, nestled approximately 1.5 million kilometers away from Earth. This strategic orbit offers the distinct advantage of providing continuous and unobstructed solar observations, eliminating any concerns of occultation or eclipses. This real-time vantage point is poised to revolutionize our understanding of solar activities and their cascading impacts on space weather. ISRO’s Twitter announcement on July 14 hinted at the impending launch readiness of Aditya-L1.
The launch vehicle designated for Aditya-L1 is the Polar Satellite Launch Vehicle (PSLV) XL, carrying a payload of seven instruments. The mission’s objectives encompass comprehensive studies of the Sun’s corona through visible and near-infrared rays, the Sun’s photosphere via soft and hard X-rays, the chromosphere utilizing ultraviolet wavelengths, solar emissions, solar winds, flares, and Coronal Mass Ejections (CMEs). The mission’s hallmark feature involves round-the-clock imaging of the Sun.
Despite the scientific promise, Aditya-L1 grapples with unique challenges. Unlike the relatively closer Moon, the Sun’s staggering distance—averaging around 150 million kilometers—presents a substantial hurdle. The mission innovatively addresses this hurdle by introducing moving components, which, while groundbreaking, introduce heightened risks of collision. Additionally, the mission must contend with the Sun’s intense temperatures and radiation in its atmosphere. However, given Aditya-L1’s significantly greater distance from the Sun, the heat challenge is expected to be manageable for the onboard instruments.
Understanding the evolution of planets, including our own Earth and exoplanets beyond our Solar System, hinges on comprehending the behavior of their parent star—the Sun. The Sun’s weather and environment cast a broad influence on the entire solar system’s dynamics, making its study imperative.
The ramifications of variations in solar weather are far-reaching, impacting satellite orbits, operational lifetimes, electronic systems, and even triggering disruptions such as power blackouts on Earth. Consequently, grasping solar events is pivotal in comprehending and predicting space weather phenomena. Notably, many instruments and components for the Aditya-L1 mission are being domestically manufactured for the first time, underscoring India’s strides in space technology.