Coronal Mass Ejections (CMEs)

 Coronal Mass Ejections (CMEs) : Recently, scientists at the Indian Institute of Astrophysics traced the rare auroras over Ladakh in May 2024 to a unique sequence of six interacting Coronal Mass Ejections (CMEs).

o Together, these CMEs caused one of the most intense geomagnetic storms in the past two decades.

• About CMEs : Are massive ejections of magnetized plasma from the Sun’s outer atmosphere, the corona.

o They are caused by magnetic reconnection—the realignment of tangled magnetic field lines on the Sun.

o When magnetic field lines snap and reconnect, they release energy that can propel CMEs into space.

o CMEs often originate near sunspot groups and may occur alongside solar flares, although not always.

o Their speeds range from below 250 km/s to over 3000 km/s; the fastest Earth-directed CMEs can reach Earth in 15–18 hours.

o CMEs expand as they travel, with large ones filling up to a quarter of the Sun–Earth distance.

o They are most frequent during the solar maximum, the peak of the Sun’s 11-year activity cycle.

• Impact on Earth: Disrupt satellite operations.

o Interfere with communication and GPS systems.

o Damage power grids and critical infrastructure.

o They also produce auroras when charged particles interact with Earth’s magnetic field.