ISRO’s Chandrayaan 2: Outstanding outcomes on the solar corona and heliophysics have been received by the Indian Space Research Organisation (ISRO) from an instrument placed aboard the Chandrayaan 2 mission. ISRO mentioned that although scientists understood the aspect concerning the origin of power of the Sun relatively properly, along with numerous other individuals of its features, there was nevertheless a great deal to be identified about the Sun, like some mysterious phenomena that could potentially adjust what we know so far. Some of these unknowns are the outer atmosphere of the Sun, known as corona, as this is exactly where emission of electromagnetic spectrum in ultraviolet and X-ray wavelengths requires spot, according to a report in PTI.
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Scientists are conscious of the reality that the solar corona has temperatures that exceed one million Kelvin due to the in depth presence of ionised gas. What’s more is the reality that the photospheric temperature of the Sun, that is the temperature of the surface of the Sun, is a mere fraction of this – 6,000 Kelvin. What has scientists stumped is that this is contrary to the organic expectation of temperature reduction as the distance from the supply of power increases. This phenomenon is referred to as the coronal heating trouble.
ISRO mentioned that based on the observations of active regions above the dark patches on the Sun getting stronger magnetic fields, known as Sunspots, professionals are of the view that the magnetic fields have an significant part to play in coronal heating. Many diverse theories have been devised to clarify what could be basically taking place, and the occurrence of a big quantity of compact solar flares (or nanoflares) is the basis of one of these theories.
Scientists have also observed that particular components in the corona are 3 to 4 instances abundant in active regions as compared to the photosphere. This happens in these components that ionise simpler or in lesser power, i.e., components getting First Ionisation Potential (FIP) reduce than 10 eV. This is the explanation why the phenomenon is referred to as FIP bias. However, although the phenomenon is identified, the explanation behind its occurrence or its origin continue to stay a mystery.
Now, a group at Department of Space’s Physical Research Laboratory (PRL) in Ahmedabad employed the Solar X-ray Monitor (XSR) onboard Chandrayaan 2 and its observations of the Sun in soft X-rays captured throughout the deepest solar minimum in the previous century to comprehend new and thrilling facts of the corona of the Sun.
ISRO mentioned that in the quiet solar corona, absolute abundances of elemental Al, Si and Mg have been derived for the initially time, and the group located and characterised about one hundred sub-A class microflares in quiet regions of the solar corona. This, ISRO mentioned, would provide new insight concerning the trouble of coronal heating.
The 98 microflares that have been observed have an intensity so low that they can’t match in the regular scale to classify them. Currently, there are 5 classes of solar flares, with every one becoming 10 instances more intense than the preceding. These classes are A, B, C, M and X. This is why these microflares have been classified as sub-A class microflares.
ISRO mentioned that this marked the initially observation as properly as statistical study of microflares in such a big quantity in the quiet portion of the Sun. This, the agency mentioned, could assistance the theory that even smaller sized flares could be present everywhere in the corona of the Sun, and that these could be the explanation behind the coronal heating.
The observation by XSM also helped in offering measurements of the abundance of many components, enabling the estimation of the abundance of low FIP components Si, Al and Mg. It was located that these abundances have been reduce in quiet corona as compared to the active regions in corona, but have been larger than the abundances in the photosphere. ISRO shared that this also marked the initially report on measurement of abundances and the lowered FIP bias in the quieter regions of the Sun.