14 DAY TRIAL // For many years, astrophysicists have believed that the Sun is an invariable star. This was supported by the fact that the star appeared not to change in brightness too much over many years. However, with the advent of modern technologies, the scientific community began looking at the Sun in wavelengths other than visible light. While peering at it in the extreme ultraviolet (EUV) portion of the electromagnetic spectrum, researchers noticed that it was actually a very variable star, so to speak.
The Hinode satellite was launched by an international group in 2006, and has been conducting scientific surveys of the Sun ever since. Not constrained by the atmosphere that surrounds Earth, it can pick up the slight variations in the temperatures of the coronal surface, and that of the actual surface of the star, that regular, ground-based telescopes simply cannot. The primary instrument on the satellite is made up of a variety of detectors that can analyze the photons emitted by the Sun, and determine a large number of their physical traits based on that. A group of astrophysicists was able to use the new data to create a fresh way of looking at why the corona is millions of degree warmer than the surface.
“Among the regions observed by Hinode is the solar chromosphere, the area separating the Sun's surface – the photosphere – from its extended atmosphere, the corona,” explains High Altitude Observatory astrophysics expert Scott McIntosh. The telescope belongs to the National Center for Atmospheric Research (NCAR), an organization that is funded by the US National Science Foundation (NSF). Scientists Bart De Pontieu, Viggo Hansteen and Karel Schrijver are also a part of the team that elaborated the new view on our star.
“Evidence indicates that radices may play an important role in supplying and replenishing the hot mass of the solar corona and wind, explaining the temperature differential between corona and photosphere. Our calculations indicate that radices can fill the corona with hot plasma even if only one to five percent of the radices reach coronal temperatures,” says McIntosh. Radices are jets of dense plasma that move very fast, are incredibly hot, and endure for very short amounts of time, LiveScience reports.