![]() ![]() He is a research scholar at NCRA and the lead author of the study. “Since the solar surface is very bright in the optical wavelengths, they cannot be used to study the solar disc,” explained Mr Surajit Mondal. Visible light is only a tiny part of this broad spectrum. The study, by researchers from the National Centre for Radio Astrophysics (NCRA) in Pune, India, was published in the journal The Astrophysical Journal Letters, and funded by the Department of Atomic Energy, Government of India.Īstronomers study the universe in all wavelengths of the electromagnetic spectrum, ranging from X-ray and gamma rays that have a smaller wavelength, to the long-wavelength radio waves. A recent study has shown that the conversion of magnetic energy to heat is somewhat random. However, little is understood about the detailed mechanism of how this happens. Some earlier observations of the Sun have also shown that magnetic phenomena in the photosphere are ultimately responsible for heating the corona. Superflares, or sudden dumping of vast amounts of energy in the solar corona, have been observed since the dawn of astronomy. The coronal heating problem continues to baffle researchers studying the Sun as well as other stars, which also have scorching coronas. What makes it more difficult for astronomers to study the corona is that it is much dimmer than the photosphere. Solar physicists call this mystery the ‘coronal heating problem’. However, the corona is more than a hundred times hotter than the photosphere, unlike what one could imagine for a ball of fire. The solar corona is also the source of solar winds, which cause spectacular auroras, and can sometimes disrupt communication across the globe. © 2011- National Astronomical Observatory of Japan.The outermost layer of the Sun, known as the solar corona, extends far beyond the Sun’s surface, which astronomers refer to as the photosphere.Galaxy Clusters Depicted by X-ray Spectroscopy.Exploring Galaxies 12.8 Billion Light-years away with SDF.Exploring the Early Cosmos through the largest Explosions in the Universe.Exploring an Active Supermassive Black Hole Buried in Cosmic Dust Using Infrared Spectroscopic Observations.Exploring the Forest of Interstellar Molecular Emission Lines.Hearing the First Cries of Newly Born Stars.X-ray Search - Rare Metals in Supernova Debris."Peculiar" Supernova Results in New Discoveries.Stars in Globular Clusters - Compositions are actually not uniform.Extremely Metal-Poor Stars - to what extent can we measure small amounts of elements?.Spectrum of the First Low-Temperature Brown Dwarf.The spectrum of debris disk sample HD165014.Iodine molecules, G-type giant star spectra, and the search for extrasolar planets.Analysis of Spectra in Astrophysics - Visiting the Old, Learning of the New.Adaptive Optics, Powerful in Spectroscopic Observations, as Well.Echelle Spectrographs: instruments covering a Wide Wavelength Range with High Spectral Resolution.Bargain Observations “Multi Object Slits Spectroscopy”.Previous : Measurement of Solar Magnetic Field.Yukio Katsukawa Data Date OctoObject the Sun Instrument Extreme-ultraviolet Imaging Spectrometer (EIS) on Hinode Wavelength Extreme-ultraviolet Analysis of the emission lines of the ionized iron yields information on the temperature of the corona. In such a hot corona, a part of the electrons is removed from iron atoms, and more electrons are removed at higher temperature. Iron, with the symbol Fe, is atomic number 26 and will have 26 electrons. The most frequent lines are emission lines originating in ionized iron. We can find many spectral lines radiating from high temperature (higher than one million Kelvin) plasma. The extreme-ultraviolet is a wavelength range of the shorter wavelength region of ultraviolet radiation. The observational satellite Hinode's onboard instrument, called Extreme-ultraviolet Imaging Spectrometer (EIS), was designed for obtaining spectra of the solar corona. That is the reason why we need a space observatory. ![]() However, ultraviolet and X-ray radiation cannot penetrate the Earth's atmosphere. The high-temperature corona emits more radiation at shorter wavelength. Observations at shorter wavelength light such as ultraviolet and X-ray are appropriate to investigate the corona in detail. In visible light, the bright solar surface hampers observation of the faint corona. To observe the corona surrounding the Sun, we have to wait for an opportunity to view a total solar eclipse when the Moon fully blocks the solar disk. ![]()
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