CAA’s Articulate – Solar orbiter reveals sun’s tiny ‘campfires’


Context: 

  • A European Space Agency and NASA’s solar orbiter has delivered the closest photos ever taken of the sun’s surface.

More on the news:

  • The photos revealed a landscape rife with thousands of tiny solar flares that scientists dubbed “campfires”. 
    • It is offering clues about the extreme heat of the outermost part of its atmosphere.
  • The spacecraft has taken the images using the orbiter’s Extreme Ultraviolet Imager as it orbited nearly 77 million km from the sun’s surface.
    • The spacecraft also carries plasma-sampling instruments to offer researchers further data.
    • That combination will help in making links and connections between what is happening on the sun and what is happening at the spacecraft.

Importance of findings:

  • The campfires are believed to be tiny explosions, called nanoflare and could be helpful in explaining why the sun’s outer shield – the corona – is 300 times hotter than the star’s surface. 
  • Earlier, scientists have relied upon Earth-based telescopes for close-ups of the sun’s surface. 
    • But Earth’s atmosphere limits the amount of visible light needed for clearer views as intimate as those obtained by the Solar Orbiter.

Solar Flares: 

  • They are large explosions of magnetic energy in the Sun’s atmosphere which causes an intense burst of energy particles that results into increased brightness and occur in active regions around sunspots.
  • When these particles interact with Earth’s magnetosphere, they can cause magnetic storms that can disrupt telecommunication networks and power grids on the ground.

Source: astronomy.com


Corona: 

  • The outermost layer of the Sun’s atmosphere that extends millions of kilometres into outer space.
  • Its temperature is more than a million degrees Celsius, which is hotter than the surface of the Sun (5500 °C).

About Solar Orbiter Mission:

  • It is a space mission of international collaboration between European Space Agency (ESA) and NASA. The spacecraft was launched from Cape Canaveral, Florida in February 2020.
  • It was selected as the first medium-class mission of ESA’s Cosmic Vision 2015-2025 Programme.
  • Solar Orbiter follows the Ulysses spacecraft, another collaboration between ESA and NASA that launched in 1990.
  • Primary mission: The solar probe’s primary mission is to examine the sun’s polar regions.
  • This will help researchers understand the origins of the solar wind, charged particles that blast through the solar system and affect satellites and electronics on Earth.