‘Shooting Stars’ Discovered In The Sun’s Corona

SolO view in the EUV on 30 March 2022 showing a partial section of the Sun with gas at 1 million ... [+] degrees. The red paths correspond to some of the rain tracks analysed in this work. The Earth image has been overlaid to scale.

Images of meteor-like fireballs have been spotted in images of the sun’s corona—it’s mysteriously hotter outer atmosphere.

They were sent back by the European Space Agency’s Solar Orbiter spacecraft while it was a third of the way to the sun from Earth in spring 2022. Its images of the solar corona, which were taken from 30 million miles away, are the highest resolution ever taken.

The solar corona—which will be visible to the naked eye during the total solar eclipse on April 8, 2024 in North America—comprises million-degree gas. It’s much hotter than the sun’s surface, which remains a mystery to solar physicists.

The research, published in Astronomy & Astrophysics, observed spectacular magnetic displays in the corona called coronal rain—charged plasma cooling and condensing along magnetic fields.

SolO view in the EUV on 1 April 2022 showing a partial section of the Sun with gas at 1 million ... [+] degrees. The red paths correspond to some of the rain tracks analysed in this work. The Earth image has been overlaid to scale.

“The inner solar corona is so hot we may never be able to probe it in situ with a spacecraft,” said lead author Patrick Antolin, Assistant Professor at Northumbria University, talking today at the National Astronomy Meeting (NAM 2023) at Cardiff University in the U.K. “Just detecting coronal rain is a huge step forward for solar physics because it gives us important clues about the major solar mysteries, such as how it is heated to millions of degrees.”

Rapid drops in temperature within the corona produce fiery and dense balls of plasma hundreds of miles wide that heat up to a million degrees, then cool as they fall towards the sun.

“If humans were alien beings capable of living on the sun’s surface, we would constantly be rewarded with amazing views of shooting stars,” said Antolin. It appears that most of these ‘shooting stars’ make it to the solar surface intact.

Rain clump and fireball. Left panel: Section of the Sun seen with SolO. The gas is at 1 million ... [+] degrees. Middle panel: Zoomed-in region of the white rectangle in the left panel, showing the trajectories of the rain clumps in red. The black arrows indicate various rain clumps seen as darker patches. Right panel: Zoomed-in region of the cyan rectangle in the middle panel, showing a rain clump (black arrows), with a bright region underneath that corresponds to the fireball effect due to compression and heating.

Solar Orbiter—which was launched in early 2020—has been getting astronomers unique close-up images of the corona that reveal small-scale phenomena for the first time. It has twice the spatial resolution compared to NASA’s Solar Dynamic Observatory (SDO).

It has a suite if 10 different scientific instruments including the six ultraviolet imaging telescopes that are able to take the first telescope observations from close to the sun—as well as the first images of the north and south poles of the sun.

NASA’s Parker Solar Probe gets closer to the sun than Solar Orbiter, but it lacks telescopes so cannot directly image the sun.

Wishing you clear skies and wide eyes.