This week marks the celebration of Earth Day on April 22. On this occasion, I would like to share this amazing video, which gives a greater perspective of what is going on in our Sun. Solar flares are nothing but the ejection of superhot clouds of plasma from the Sun's corona at very high speeds even greater than 1 million miles per hour or simply put, Coronal Mass Ejection (CME). This intense radiation of plasma waves could pose threat to the on-board computer electronics of communication satellites and spacecrafts in its path and can affect the power infrastructure on the surface of these satellites and their navigation systems. It has been three years since NASA’s Solar Dynamics Observatory (SDO) orbiting our planet started sending the images of the Sun. We have witnessed several things during this period including intense solar flares, planets transiting the solar face and the amazing solar rain. This video compresses these three years of intense activity into little over 3 minutes. The spacecraft SDO captures the shot of the Sun every 12 seconds in 10 different wavelengths and the images shown in this video are based on a wavelength of 171 Angstroms, and then four synchronized wavelengths of 171, 304, 193, and 4500.
The subtle changes seen in apparent size of the Sun during the course of this video are due to the changes in orbiting distance of SDO from the Sun since SDO orbits the Earth at 6,876 miles per hour while the Earth orbits the Sun at 67,062 miles per hour. The four-wavelength view presented at the end of the video shows light at 4500 Angstroms, the visible light view of the Sun, which highlights the material at 6,000 K and reveal the Sun spots and the photosphere of the Sun; light at 193 Angstroms highlights the material at 1 million Kelvin and reveal the features in the corona, the flare plasma, and the dark areas called coronal holes, where the high-speed solar wind originates; light at 304 Angstroms highlights the material at 50,000 Kelvin and show the features in the chromosphere of the Sun; and light at 171 Angstroms highlights the material at 600,000 Kelvin and reveal the features of the quiet corona. Take a look! Credit: NASA's Goddard Space Flight Center/SDO
