Sun Boils with Earth- and Jupiter-Sized Clumps of Matter

Scientists at NASA's Solar Dynamics Observatory (SDO) have developed a new way of probing the inner depths of the Sun by collecting data from the star's atmosphere, learning there's more to the solar surface than meets the eye. 

By tracking bright points in the solar atmosphere and magnetic signatures on the Sun's surface, scientists can achieve a near-real-time map of the star's roiling interior, the SDO said Thursday.

Writing in The Astrophysical Journal Letters, a team of scientists led by the SDO's Scott McIntosh details their expedited methods for probing the depths of the Sun and the implications doing so may have on our understanding of the inner workings of the very object that fuels life on Earth.

"There are all sorts of things lurking below the surface," McIntosh said. "And we've found a marker for this deep rooted activity. This is kind of a gateway to the interior, and we don't need months of data to get there."

Previous methods for analyzing the interior of the Sun involved a technique known as helioseismology, which tracks the time it takes for waves on the solar surface to travel from one side of the Sun to another.

The solar surface is believed to be made up of matter called granules and supergranules, which are vigorously moving, much like water churning at a raging boil, but on an enormous scale.

"A granule is approximately the distance from Los Angeles to New York City; a super-granule is about twice the diameter of Earth," the SDO reported.

The new technique eschews tracking the Sun's seismic waves and instead maps the dynamic magnetic fields that form around the Sun.

By tracking differently sized, magnetically balanced areas of the Sun, the researchers can get a deeper understanding of what is going on within the star.

"Think of it like looking down at a city from above with a technology that observed people, but not walls, and recording areas that have an even number of men and women," the SDO said in a statement. "Even without seeing the buildings, you'd naturally get a sense for the size of rooms, houses, buildings, and whole city blocks -- the structures in which people naturally group."

The analysis revealed that the magnetic areas matched the size of granules and supergranules, as well as areas about the size of Jupiter.

"It's as if when searching for those pairs of men and women, one suddenly realized that the city itself and the sprawling suburbs was another scale worth paying attention to," the SDO said. "The scientists believe these areas correlate to even larger cells of flowing material inside the Sun."

These large areas, dubbed "g-nodes," also correspond to patches of intense ultraviolet and X-ray light known as brightspots.

"Imagine a bunch of helium balloons with weights on them," said study co-author Robert Leamon. "The weights get carried along by the motions at the bottom. We can track the motion of the helium balloons floating up high and that tells us what's happening down below."

The researchers said that this method could lead to a very straightforward way of mapping the Sun's interior and perhaps lead to better ways of predicting solar storms.