It is one of the most mysterious phenomena of the sun. The Euro-American Solar Orbiter probe delivered this Thursday the closest images ever taken of our solar star, revealing miniature eruptions called "campfires", which could explain the heating of the solar corona.
The Solar Orbiter mission, in collaboration with the European Space Agency (ESA) and NASA, set off on February 10 towards the sun, with ten instruments on board, including six observation telescopes. The device gives the spacecraft a unique ability to take images of the solar surface.
77 million kilometers away
"The sun has never been seen so close!" ", Anne Pacros, mission and payload manager, welcomed AFP.
At 77 million kilometers from the star (about half of the earth-sun distance), the first close-up images have highlighted a new phenomenon: "campfires", omnipresent mini-solar flares close to the surface, detailed ESA at a press conference.
These "campfires", which until now were not visible in detail, "are small compared to the giant solar flares that we can observe from the earth, millions or billions of times smaller", explained David Berghmans , from the Royal Observatory of Belgium, principal investigator of the “Extreme Ultraviolet Imager” (EUI) remote sensing instrument, which took images in extreme ultraviolet radiation.
Hitherto unexplained phenomenon
Scientists still do not know whether these "campfires" are a simple miniature version of large eruptions, or the result of different mechanisms. But theories already claim that they "could contribute to the heating of the solar corona", a phenomenon so far unexplained, explains ESA.
The solar corona, the most extreme layer of the atmosphere of the sun which extends over millions of kilometers in space, in fact exceeds a million degrees while the surface of the sun reaches "only" 5,500 degrees: this gigantic gap defies the laws of nature, which would like that the more one moves away from a source of heat, the more the temperature drops.
Understanding these mechanisms is considered to be the “Grail” of solar physics, emphasizes ESA.
Sciences
What researchers are burning to know thanks to the Solar Orbiter probe
Sciences
Solar Orbiter has started its long journey towards the Sun to better understand its mysteries
- Nasa
- Sciences
- Photo
- Sun
- Astronomy
- Space
- ESA