STEVE Phenomenon


    In News 

    • The cosmic phenomenon known as “Strong Thermal Emission Velocity Enhancement (STEVE) made a surprise appearance after a huge solar storm hit Earth.

    About STEVE Phenomenon

    • STEVE first appeared in the sky in 2017 and has been appearing often since.
      • There is evidence to support the claim that the phenomenon has been visible in the sky since 1705
    • It is a rare, mysterious, glowing purple arc that runs east to west and occurs closer to the equator
    • How does it occur?
      • The phenomenon is believed to be caused by a 25 km wide ribbon of hot plasma moving at a speed of 6 km/s (compared to 10 m/s outside the ribbon) at an altitude of 450 km
      • It has been observed in New Zealand, Canada, Alaska and the United Kingdom during a specific time of the year – between October to February which lead NASA scientists to believe that its occurrence is related to seasons. 

    How is it different from Aurora Borealis?

    • Disturbances in the Earth’s magnetosphere due to solar wind cause Auroras.
      • These disturbances occur because of enhancements in the speed of the solar wind from coronal holes and coronal mass ejections. “
    • While the skylights, STEVE and the Auroras might seem similar, they are nothing alike. 
      • To begin with, the STEVE phenomenon is closer to the equator than the Auroras. 
      • STEVE is different from the usual aurora, but it is made of light and it is driven by the auroral system. 

    Source: LM