Astronomers gazing at the sun caught a huge filament eruption on its surface.
NASA released a video of the phenomenon, which was captured with two coronagraphs, which are special instruments used to take close looks at the sun. Both the Large Angle Spectrometric Coronagraph (LASCO) and the Solar and Heliospheric Observatory (SOHO) are collaborations of NASA and the European Space Agency (ESA).
"An elongated solar filament that extended almost half the sun's visible hemisphere erupted into space on April 28-29, 2015, in a large burst of bright plasma," NASA said in a statement. "Filaments are unstable strands of solar material suspended above the sun by magnetic forces. Solar astronomers around the world had their eyes on this unusually large filament and kept track as it erupted. Both of the coronagraph instruments... show the coronal mass ejection associated with the eruption.
"LASCO... is able to take images of the solar corona by blocking the light coming directly from the Sun with an occulter disk, creating an artificial eclipse within the instrument itself. C2 images show the inner solar corona up to 8.4 million kilometers (5.25 million miles) away from the Sun. C3 images have a larger field of view: They encompass 32 diameters of the Sun. To put this in perspective, the diameter of the images is 45 million kilometers (about 30 million miles) at the distance of the Sun, or half of the diameter of the orbit of Mercury. The white circle in the center of the round disk represents the size of the sun, which is being blocked by the telescope in order to see the fainter material around it."
