NASA's IRIS spacecraft, which was launched this summer in order to explore a not-well-observed part of the Sun known as the interface region, has produced some unprecedented images of the Sun, people involved with the project said Monday.
The Interface Region Imaging Spectrograph, or IRIS, spacecraft's mission is to document the layer of atmosphere between the Sun's surface and its corona. The latest data from IRIS reveal the interface region to be more violent than previously thought, with a high-velocity torrent of solar gases heated to hundreds of thousands of degrees while swirling around at high speeds.
"We are seeing rich and unprecedented images of violent events in which gases are accelerated to very high velocities while being rapidly heated to hundreds of thousands of degrees," said Bart De Pontieu, the IRIS science lead at Lockheed Martin Palo Alto, Calif. "These types of observations present significant challenges to current theoretical models."
IRIS scientists hope that by studying this region of the Sun they will gather data sufficient to determine the role it plays in heating the solar atmosphere.
Scientists said the region has always been known to be dynamic, but these latest images prove it to be even more violent and turbulent than imagined. They have turned their focus on two types of solar events revealed by the IRIS images: prominence and spicule.
Prominence is a solar event in which cooler zones within the interface region appear as giant loops of material rising up above the solar surface. When these prominences erupt, they lead to solar storms that can sometimes reach Earth. The IRIS images reveal what NASA called "highly dynamic and finely structured flows sweeping throughout the prominence."
Spicules are giant fountains of gas, which at their height can shoot as high in the solar atmosphere as Earth is around. These high-speed events zoom up from the Sun's surface at 150,000 mph.
"Spicules may play a role in distributing heat and energy up into the sun's atmosphere, the corona. IRIS imaging and spectral data allows us to see at high resolution, for the first time, how the spicules evolve," NASA said in a statement.
The direct observations of prominence and spicules by IRIS show that the solar events are more complex than what theoretical models predicted.
"We see discrepancies between these observations and the models and that is great news for advancing knowledge," said Mats Carlsson, an astrophysicist at the University of Oslo in Norway. "By seeing something we don't understand we have a chance of learning something new."
Rendering these solar images is not as simple as pressing a button and uploading the picture to the Internet. Powerful supercomputers are required to process the IRIS data. An hour of solar observations can take several months of computer time to render.
NASA said the IRIS project is helping to complete the picture of the Sun and provide a more complete understanding of they dynamics of our star.
"Now, IRIS provides unprecedented information about the crucial layer in between, to finally help us understand how energy moves through the lower levels of the solar atmosphere driving the solar wind and heating the corona," the space agency said in a statement.