These observations may have unravelled why the Sun’s atmosphere is hotter than its surface. It starts increasing outside the photosphere, reaching a value of about one million degrees or more in the corona. Spicules in the SunThe key to the puzzle lies in geyser-like jets known as solar spicules that emanate from the interface of the corona and the photosphere. While in a photograph these look like tiny hairlike projections, they are in fact 200-500 kilometres wide and shoot up to heights of about 5,000 km above the solar surface. The researchers also matched these observations with simultaneous observations form the Atmospheric Imaging Assembly in NASA’s Solar Dynamic Observatory spacecraft.

Source: The Hindu November 16, 2019 14:14 UTC