India's Aditya-L1 Mission to Observe Solar Maximum in 2026
India's first solar observation mission, Aditya-L1, is scheduled to monitor the Sun during its peak activity cycle in 2026. The observatory, launched last year, will observe the Sun as it transitions to a period of increased activity, a phenomenon that occurs approximately every 11 years. This cycle involves the reversal of the Sun's magnetic poles and is characterized by a rise in solar storms and coronal mass expulsions (CMEs).
Coronal Mass Expulsions (CMEs)
CMEs are significant expulsions of plasma and magnetic fields from the Sun's outermost atmospheric layer, the corona. These events can involve up to a trillion kilograms of charged particles and can achieve speeds of up to 3,000 kilometers per second (1,864 miles per second). At maximum velocity, a CME could travel the 150 million kilometer distance between the Sun and Earth in approximately 15 hours.
Prof. R Ramesh, principal investigator for the Visible Emission Line Coronagraph (Velc) on Aditya-L1 and affiliated with the Indian Institute of Astrophysics (IIA), stated that during periods of low solar activity, the Sun typically produces two to three CMEs daily. This rate is projected to increase to 10 or more CMEs daily during the 2026 solar maximum.
Scientific Objectives and Terrestrial Impact
A primary scientific objective of the Aditya-L1 mission is the study of CMEs. This research contributes to understanding the Sun and provides data regarding potential impacts on Earth-based and orbital infrastructure.
CMEs can induce geomagnetic storms, which affect the space environment where an estimated 11,000 satellites, including 136 Indian satellites, are currently operating. While CMEs are not typically a direct threat to human life, geomagnetic storms can cause:
- Malfunctions in satellite electronics.
- Disruption of power grids.
- Impacts on weather and communication satellites.
Auroras, such as the aurora borealis, are a visible result of charged particles from the Sun interacting with Earth's atmosphere.
Historical Context and Predictive Capacity
Historical records include the Carrington Event of 1859, a powerful solar storm that disrupted telegraph lines globally. More recent events include:
- A 1989 incident that caused a nine-hour power outage affecting six million people in Quebec.
- Solar activity in November 2015 that disrupted air traffic control in Sweden and other European airports.
- The reported loss of 38 commercial satellites due to a CME in February 2022.
Prof. Ramesh indicated that real-time observation of solar storms and CMEs from the Sun's corona, including data on their origin temperature and trajectory, could provide advance warning. Such a system would enable measures like switching off power grids and satellites or relocating them to mitigate potential damage.