NASA spacecraft spots plasma 'bombs' on sun's surface

PALO ALTO, Calif., Oct. 17 (UPI) —

NASA’s Interface Region Imaging Spectrograph probe has captured new detailed images of several mysterious solar phenomena known as plasma "bombs," nanoflares, and supersonic jets that may generate solar winds.

Thanks to the IRIS space telescope and its newly captured images, astronomers are learning more and more about the little-understood transitional region between the sun’s surface, or its photosphere, and its outer atmosphere, the corona. This intermediary region is where said bombs, nanoflares and jets take shape.

"This region is believed to be where the solar wind originates, and these jets are the most prominent dynamic features in this region," Dr. Hui Tian, an astronomer at the Harvard-Smithsonian Center for Astrophysics, told Australia’s ABC Science.

"This unprecedented high resolution lets us examine various types of previously unseen features such as very small scale intermittent high speed jet-like structures in the interface region," Tian said of IRIS’s impressive imaging capabilities.

In addition to the unique jet-like propulsions of plasma particles, described by Tian, astronomers also observed a number of nanoflares, a dramatic reconnection and disconnection of magnetic field lines — the same process that generates solar flares, only on a smaller scale. But perhaps the most interesting of all the newly studied features is the sun’s so-called plasma bomb.

Plasma bombs, scientists explain, occur when the sun converts some of its magnetic energy into thermal energy. Cooler gas in the intermediary region is quickly heated, forming a pocket that eventually bursts like a highly pressurized balloon. Some of the exploded hot gas is ejected into the corona, creating an updraft, while some cools and falls back toward the photosphere, creating downdrafts.

"These unexpected results will likely lead to a reassessment of other phenomena in the low solar atmosphere," Alan Title, IRIS principal investigator, said in a press release.

"This set of research really delivers on the promise of IRIS, which has been looking at a region of the sun with a level of detail that has never been done before," added Bart De Pontieu, the project’s lead scientist. "The results focus on a lot of things that have been puzzling for a long time and they also offer some complete surprises."

The IRIS data inspired a total of five new scientific papers, all published in the journal Science this week, each detailing one of the various new solar phenomena.