Highest-ever resolution images of Sun reveal million-degree threads in dark spots

Science: Newly released images of the Sun are the highest-resolution pictures of our star ever taken and they reveal its atmosphere is much more complex than first thought 

Scientists from the University of Central Lancashire and NASA's Marshall Space Flight Center studied the images taken by the space-based NASA High-Resolution Coronal Imager telescope.

The pictures revealed that parts of the Sun's atmosphere, thought to be dark or mostly empty, are filled with strands of hot electrified gasses 311 miles wide. 

Each of those strands are up to 1.8 million degrees Fahrenheit and are larger than the distance between London and Belfast, according to researchers.

NASA's Hi-C telescope can pick out structures in the Sun's atmosphere as small as 43 miles in size - or about 0.01 per cent of the total size of the star.

It was able to capture the incredibly fine magnetic threads in the 'dark areas' and scientists say they are made of extremely hot, million-degree plasma.

What exactly created these strands remains unclear, according to the Lancashire research team, although it will now become a focus for astronomers.

The Hi-C, the telescope that captured the images, is a unique astronomical telescope carried into space on a sub-orbital rocket flight. 

The telescope launches to the edge of space where it then captures images of the star every second before returning to Earth after five minutes. 

The international team of researchers behind the discovery and the telescope are now working on plans to launch the Hi-C rocket mission again.

Next time overlapping their observations with two Sun-observing spacecraft currently gathering further data, NASA’s Parker Solar Probe and ESA’s Solar Orbiter.

Dr Amy Winebarger, Hi-C principal investigator at NASA MSFC stated: 'These new Hi-C images give us a remarkable insight into the Sun's atmosphere. 

'Along with ongoing missions such as Probe and SolO, this fleet of space-based instruments in the near future will reveal the Sun's dynamic outer layer in a completely new light.' 

Scientists will debate why they are formed and how their presence helps us understand the eruption of solar flares and solar storms.

Those are events from the Sun that could directly affect life on Earth.

Tom Williams, a postdoctoral researcher at UCLan who worked on the Hi-C data, said the images would help provide a greater understanding of how the Earth and Sun related to each other.

'This is a fascinating discovery that could better inform our understanding of the flow of energy through the layers of the Sun and eventually down to Earth itself.'

'This is so important if we are to model and predict the behaviour of our life-giving star', he added.

Robert Walsh, professor of solar physics at UCLan, said the images provided an 'ultra-high definition' glimpse of the Sun for the first time. 

'Until now, solar astronomers have effectively been viewing our closest star in 'standard definition', Walsh said.

'The exceptional quality of the data provided by the Hi-C telescope allows us to survey a patch of the Sun in 'ultra-high definition' for the first time.' 

The images show the outer layer is filled with previously unseen fine magnetic threats of hot plasma - giving a deeper insight into the make up of the star. 

'Think of it like this: if you are watching a football match on television in standard definition, the football pitch looks green and uniform,' said Walsh.

'Watch the same game in ultra-HD and the individual blades of grass can jump out at you – and that's what we're able to see with the Hi-C images. We are catching sight of the constituent parts that make up the atmosphere of the star.' 

The research has been published in the Astrophysical Journal.