What are Auroras?

May 2, 2023

The Indian Astronomical Observatory (IAO) above Mount Saraswati captured a rare phenomenon as a geomagnetic storm struck Earth's magnetic field, creating unique auroras.

Why in News?

  • The auroras are normally seen at higher altitudes in parts of Alaska, Norway, and other countries.
  • This was the first time that the aurora was captured on camera in India by the Indian Astronomical Observatory.
  • The 360-degree camera atop the IAO in Ladakh Hanle captured the mysterious phenomenon, which is triggered by an interaction between the plasma particles hurled by the Sun and Earth's magnetic field.

About Auroras:

  • How is it formed? The sun is ejecting charged particles from its corona, creating solar wind. When that wind slams into Earth's ionosphere, the aurora is born.
  • In the Northern Hemisphere, the phenomenon is called the northern lights (aurora borealis), while in the Southern Hemisphere, it's called the southern lights (aurora australis).
  • The hemispheric asymmetry of the aurora is due in part to the sun's magnetic field interfering with Earth's magnetic field.

STEVE

  • Another aurora-like occurrence on Earth is STEVE (Strong Thermal Emission Velocity Enhancement).
  • It is a glowing atmospheric phenomenon, but it looks slightly different from its undulating auroral counterparts.
  • Like the northern and southern lights, STEVE is also visible from lower latitudes, closer to the equator, than the auroras.