The Sun’s corona – the outermost layer, which can reach temperatures above one million degrees Celsius – is chemically very different from the rest of the star, although it is physically connected.
Astronomers have not been able to explain and prove this phenomenon for more than half a century, making it one of the enduring mysteries of astronomy.
Researchers have now discovered the first observations showing that magnetic waves in the chromosphere – the middle layer of the Sun – split the plasma, forcing only charged ions into the corona and leaving neutral particles.
A document released today by astronomers from University College London and the Italian Space Agency provides the first evidence to support this long-standing theory.
Researchers have discovered the first observations showing that magnetic waves in the chromosphere – the middle layer of the Sun – split the plasma, forcing only charged ions into the corona and leaving neutral particles.
Researchers analyzed data from telescopes in New Mexico as well as in space to observe the same part of the Sun at the same time in an attempt to find the waves.
The observed models were recreated using computer modeling, and the scientists found that the waves reflected in the chromosphere were magnetically linked to areas with abundant ionized particles in the corona.
“These results show a link between the chromospheric activity of sunspots and the observed changes in coronal plasma composition,” the researchers wrote in their study, published today in The Astrophysical Journal.
The theory of magnetic waves separating the plasma and forcing ions to the corona was first introduced in the 1960s.
What causes the waves remains unknown, but scientists believe they are generated in the volatile corona by millions of mini-explosions known as nanoflarers.
Dr Deborah Baker, lead author of the study, told MailOnline: “The different chemical compositions of the inner and outer layers of the sun were first observed more than 50 years ago.
“This discovery has raised one of the long-standing open questions in astrophysics.
“The difference in composition is surprising, given that the layers are physically connected and that the matter in the crown originates from the innermost layer, the photosphere.
“Now, thanks to a unique combination of terrestrial and cosmic observations of the solar atmosphere, conducted almost simultaneously, it was possible to finally detect magnetic waves in the chromosphere and connect with the abundance of elements in the corona that are not in the inner regions of the Sun. ‘
Dr Marco Stangalini of the Italian Space Agency in Rome says the findings are true for other stars as well as the sun.
“By observing our local laboratory, the Sun, we can improve our understanding of the universe far beyond,” he said.
The theory of magnetic waves separating the plasma and forcing ions to the corona was first introduced in the 1960s. What causes the waves remains unknown, but scientists believe they are generated in the volatile corona by millions of mini-explosions known as nanoflora. Pictured is the surface of the Sun.
Now astronomers are more interested in the Sun’s corona than ever because of its role in creating the solar wind.
The solar wind, which carries ions 92 miles from the Sun to Earth, creates the Northern Lights and Southern Lights.
As these charged particles reach the Earth’s magnetic field, which is the most powerful of the poles, they release energy, and this manifests itself as the mesmerizing celestial light show we see on Earth, visible at high and low latitudes.
However, when the constant flow of charged particles turns into a flood after a strong orig from the Sun’s surface, it can affect delicate electrical systems and satellite-dependent industries.
“Identifying the processes that make up the corona is crucial because we are trying to better understand the solar wind, the flow of charged particles leaking out of the sun that can disrupt and damage Earth’s satellites and infrastructure,” he said. Dr. Baker.
“Our new discoveries will help us analyze the solar wind and trace it back to where it comes from in the Sun’s atmosphere.”
Sun’s Campfires: Solar Orbiter Captures ‘Closest Photos’ of 47 Miles of the Sun
The UK-built European space agency Solar Orbiter captured the closest images ever taken to the Sun and did so while flying between the orbits of Venus and Mercury, according to the UK space agency.
The stunning images taken by the Solar Orbiter while 47 miles from the surface of our host star include signs of mini-solar flares, called “campfires” by scientists behind the probe.
Solar flares are short bursts of high-energy radiation from the Sun’s surface, and these “campfires” are millions of times smaller than normal star flares.
The images were taken in mid-June while the Solar Orbiter is still in the testing phase, so the team says the images will become higher resolution as the probe approaches the Sun.
As it approaches our star, the Solar Orbiter will be 26 million miles from the Sun’s surface – that’s closer than 37 million miles from Mercury’s Sun and will reach the end of next year.
The most important discovery is the presence of these “campfires”, also known as “nano-eruptions”, which are visible scattered on the surface of the Sun, astronomers explained – they are bright and dynamic eruptions.