NASA Administrator Daniel Goldin presented highly detailed, enlightening images of the sun at a press conference Tuesday morning. Taken by NASAs Transition Region and Coronal Explorer (TRACE) satellite, the images bring solar physicists one step closer to answering many questions about the intricate mechanics of the solar surface and atmosphere.

According to Goldin, astronomers working with the new TRACE images have in fact solved a mini-mystery about hot electrified gas ejections from the sun called coronal loops. They found that these large loops of energy, which comprise the solar corona (the suns outermost gaseous layer), are heated to millions of degrees Fahrenheit directly at the loops bases a direct negation of a previous theory that proposed the loops are heated uniformly.

"Being able to understand how the sun works is very, very important," said Goldin, who presented the latest images at the American Museum of Natural Historys Rose Center for Earth and Space in New York. "We didnt understand where the energy was going into these coronal arcsbut with this data were finding the heating is going in right at their base. We hope that this will help our scientists better understand this [looping] phenomenon."

Scientists are particularly interested in studying the suns corona because it is in this layer that dangerous solar ejections of gas and charged particles are thought to originate. Called coronal mass ejections, these huge spurts of energy shoot out from the sun and quite often reach Earth, sometimes causing disruption of power stations, satellite systems and other technologies on which humans depend.

TRACEs newest observations show that coronal loops form when huge gas fountains are heated by a yet unknown energy source located near the loops bases, roughly 10,000 miles (16,000 kilometers) above the suns visible surface. Scientists have found that the suns coronal loops are heated to as much as 1,000 times the temperature of the suns visible surface, or about 3 million degrees Fahrenheit (1.7 million degrees Celsius).

"The mysterious energy source that makes the suns atmosphere so incredibly hot has been an enigma for more than 70 years," said Dr. Markus Aschwanden, a researcher at the Lockheed Martin Solar and Astrophysics Laboratory and the lead author of a paper on TRACEs newest data, which is pending publication in the Astrophysical Journal. "Locating the source of coronal heating is a key piece of this puzzle."

Coronal loops, which constantly emerge and disappear all over the suns surface, can span a length of about 250,000 miles (400,000 kilometers), or about 30 times the diameter of Earth. Every now and then, one or more of the loops (which is actually a composite of a bundle of smaller gas loops) somehow "snap open" in the form of a mass coronal ejection, releasing gas and particles out into space. Understanding exactly how and why these coronal mass ejections snap open may soon help researchers predict dangerous solar weather.

Being able to predict when major solar ejections will hit Earth is possible because although light from the sun reaches us in about 10 minutes, coronal flares take between one and four days to reach the planet. As a result, if we can detect these ejections shortly after they occur with space-based satellites, we can "begin to take action to prevent some of the problems we see here," said Goldin.

TRACE is one of two major space satellites currently studying our nearest star in great detail. The other, the joint European Space Agency/NASA Solar and Heliospheric Observatory (SOHO), has also been capturing some stunning images of the sun, though its emphasis has been on global solar phenomena as opposed to closeups of small sections of the solar surface. Observations from both TRACE and SOHO are also helping astronomers understand stellar dynamics in general, since other stars are too distant to study with this degree of detail.