Washington: The space telescope IRIS researchers have found evidence of such short-lived heat pockets in the Sun and showed that the temperature distribution within the Sun's outer layers could occasionally turn topsy turvy.
Researchers with the lead of the Max Planck Institute for Solar System Research (MPS) in Germany have received the data from NASA's space telescope IRIS (Interface Region Imaging Spectrograph).
Scientists insisted that the Sun was an incredibly hot place, but even though in all its layers the temperatures were daunting, some were hotter than others. With a temperature of approximately 5,000 degrees, the Sun's visible surface, the photosphere for example, was comparatively cool. Going outward from there, the temperatures within the Sun's atmosphere rose gradually until they reach one million degrees.
The researchers believed that the strong magnetic fields in the photosphere provided the necessary energy for such explosions. In the area of the sunspots, the magnetic field lines protruded in a loop-like fashion from the Sun's surface and hot plasma would flow there. When these flows are short-circuited, the explosions occur.
Prof. Dr. Hardi Peter said that their analysis showed, that this temperature distribution was not the same everywhere and was constantly in motion.
The regions within the photosphere were characterized by high magnetic field strengths and were the "birth places" of the dark sunspots, which cover the Sun's surface and in these regions they found heat pockets as big as half of Germany. They were up to 20 times as hot as their surroundings.
The researchers discovered characteristic wavelengths that special highly ionized atoms within the solar plasma such as triply ionized silicon ions emit into space and only under such conditions could silicon lose three of its electrons.
Through the spectral data from IRIS they were able to infer the density of the solar plasma where the radiation originated and the new results have fundamentally changed the understanding of the Sun's outer buildup, said the lead researcher.
Their findings will be published in Science Magazine.