New observations of the sun could help develop better solar thermometer

(Image: Pixabay CC0) A sophisticated new observation of a cool zone on the surface of the sun could help scientists develop a new kind of solar thermometer. A team of astrophysicists led by researchers from the University of Glasgow are the first to use observations from the ALMA observatory in Chile to estimate the temperature of a solar prominence. Solar prominences are zones of plasma on the surface of the sun which are contained by its powerful magnetic fields at a temperature much lower than neighbouring areas. While areas of the sun can exceed a million degrees Kelvin, the centres of solar prominences are usually between 5,000 and 8,000 degrees. They can last for weeks before becoming unstable and erupting outwards into space. In a paper published in the journal Monthly Notices of the Royal Astronomical Society: Letters , the researchers outline how they harnessed the ALMA observatory's ability to generate high-resolution images of the sun using data collected from across its array of radio antennas. This process, known as interferometry, allowed them to make a detailed examination of the temperature of a solar prominence which occurred on 19 April 2018.