- The Indian Astronomical Observatory located over Mount Saraswati in Hanle, Ladakh, India, captured aurora lights on its camera.
- An intense geomagnetic storm that hit Earth resulted in mesmerising auroras in several regions of Earth, including Ladakh.
- It is extremely rare to see auroras at latitudes as low as those of Ladakh.
- Auroras are seen only in high-latitude regions, near the Arctic and Antarctic circles, which are situated about 66.5 degrees north and south of the equator.
What are ‘Auroras’?
- Auroras are a natural phenomenon caused by magnetic storms initiated by the Sun’s activity such as solar flares and coronal mass ejections.
- They are visible as bright lights in the sky and are known as aurora borealis or northern lights near the North Pole and aurora australis or southern lights near the South Pole.
- Typically, auroras are seen in regions closer to the Earth’s poles due to weaker magnetosphere, but during strong solar storms, they can be visible further away from the poles.
How ‘aurora’ forms?
- The Sun constantly emits a solar wind, which is composed of charged particles and flows outward into the solar system.
- When the solar wind encounters the Earth’s magnetic field, it can trigger a process called magnetic reconnection.
- This explosive process allows charged particles from space to be accelerated into the atmosphere.
- The charged particles from the solar wind are guided around the Earth’s magnetosphere and eventually become trapped in the magnetosphere’s long tail.
- When magnetic reconnection occurs, these particles are accelerated towards the Earth’s poles.
- Along the way, particles may collide with atoms and molecules in Earth’s upper atmosphere, providing the atoms with extra energy that is released as a burst of light.
- When we see the glowing aurora, we are witnessing a billion individual collisions that light up Earth’s magnetic field lines.
Why are northern lights visible only in winters?
- During the winter, the northern regions have long periods of darkness, making it easier to see the Northern Lights.
- In the summer, the polar regions have nearly continuous daylight, making observation difficult.
- Solar phenomena which caused auroras in Ladakh
- The Sun released a coronal mass ejection towards Earth.
- The coronal mass ejection was linked with an M1 solar flare.
- A coronal mass ejection is a large expulsion of plasma and magnetic field from the Sun’s corona, and travels outward from the Sun.
- Solar flares are flashes of light that occur on the Sun in various wavelengths.
- When magnetic energy is released from sunspots, intense bursts of radiation, or solar flares occur.
- The auroras were observed in lower-than-usual latitudes.
- The last time such a severe geomagnetic storm occurred was in 2015, and that the event resulted in rare sightings of auroras in Europe, China and Ladakh.
SOURCE: THE HINDU, THE ECONOMIC TIMES, PIB