The European Space Agency’s (ESA) Solar Orbiter has captured the closest photos of the Sun to date, revealing a new feature that could provide clues about the mysterious phenomenon known as coronal heating.
Dubbed ‘campfires,’ what looks like miniature solar flares were spotted near our star’s surface and appear throughout the latest images. “The campfires are little relatives of the solar flares that we can observe from Earth, a million or billion times smaller,” explained David Berghmans, Principal Investigator of the instrument that captured the first image set of the mini flares, the Extreme Ultraviolet Imager (EUI).
The naming of these features is actually a bit ironic. Coronal heating is essentially the opposite effect of what’s experienced around a campfire on Earth – the fire’s heat is highest when near the flames and cools as one moves farther away. On the Sun, the opposite is true. While its surface is a 10,000° F inferno, the upper atmosphere (corona) is measured in the millions of degrees.
One of scientists’ preliminary theory about the new flares is that they may play a part in creating the excessive coronal heat. “These campfires are totally insignificant each by themselves, but summing up their effect all over the Sun, they might be the dominant contribution to the heating of the solar corona,” proposed Frédéric Auchère, Co-Principal Investigator of the EUI. As more observations are made by the Solar Orbiter’s other instruments, along with more images from the EUI, the project’s scientists hope to find those answers and more.
ESA’s Solar Orbiter was launched on February 10, 2020, aboard an Atlas V rocket. Its primary missions are studying the Sun up close, taking the first high-resolution images of the Sun’s poles, and understanding connections between the Sun and Earth. Along with the EUI, nine other instruments are aboard the orbiter including a Solar Wind Plasma Analyser and X-ray Spectrometer/Telescope.
These latest findings bode well for the Agency’s goals overall and add to the growing body of science surrounding our Sun. You can watch an animation of the campfires in the below video published by the ESA.