The European Space Agency (ESA) has released a video based on data from its Solar Orbiter mission, illustrating the increase in solar activity over the past three years.
Solar activity is not constant; it undergoes cyclical changes, most notably an 11-year cycle characterized by a rapid increase in sunspots, accompanied by powerful solar flares and coronal mass ejections, followed by a slower decrease.
The ESA video demonstrates the Sun approaching the peak of its activity in the current cycle, as observed from the Solar Orbiter spacecraft. The orbiter follows an elongated orbit around the Sun, coming as close as 42 million kilometers and retreating to 136 million kilometers every six months, resulting in varying apparent sizes in the footage. The sharp changes in distance correlate with periods when the spacecraft was not actively observing.
The video combines ultraviolet images of the solar corona (yellow) captured by the EUI instrument with the sizes and locations of solar flares (blue circles) recorded by the STIX instrument. Data from the Solar Orbiter spans a three-year period.
The video is sonified, with the audio track based on the intensity of solar flares and the distance of the spacecraft from the Sun. This is represented by a low background hum that increases in volume as the Solar Orbiter approaches the Sun and decreases as it moves away.
Previously, research on annual rings revealed evidence of a superflare that occurred on the Sun 2,600 years ago.