University of Sheffield researchers have made a major breakthrough to help scientists measure the size of stars planted outside our solar system more accurately.
Led by Dr Marco Stangalini of the Italian Space Agency and Dr Gary Verth and Prof Viktor Fredun from the University of Sheffield, the team of researchers have developed a new model to explain the waves detected from a large sunspot on the surface of the sun.
The sunspot in question is around three times larger than the diameter of the earth. Large sunspots such as this contain a wide variety of waves which can have both magnetic and acoustic characteristics, thus being known as magneto-acoustic waves. Data from the Dunn Solar Telescope in New Mexico has provided clear evidence of this, leading the team from the University of Sheffield to create a model to match this data.
The results of this study suggest improvements that can be made to models currently used to measure the size and structure of stars outside our solar system. At present these models only concern acoustic waves but adding in the effect of magneto-acoustic waves produced by large starspots can increase the accuracy of measurements.
Professor Viktor Fedun of the University of Sheffield’s Department of Automatic Control and Systems engineering said: “What we discovered through this research is that the frequency power spectrum of the rich variety of magneto-acoustic oscillations inside the sunspot have a completely different character to the spectrum of the Sun’s global acoustic oscillations. In fact, the structure of the frequency spectrum of the sunspot has a far more complex nature, creating challenging new questions to answer for solar researchers.
“Our findings also have important implications for astrophysicists who interpret the frequency power spectra of stars that are far more magnetically active than the Sun using purely acoustic models.”
