The TRACE images may be used without restrictions in publications of any kind. We appreciate an acknowledgement indicating that the Transition Region and Coronal Explorer, TRACE, is a mission of the Stanford-Lockheed Institute for Space Research, and part of the NASA Small Explorer program. More information on TRACE and other TRACE images can be found here.

	On 11-Nov-2008, TRACE was observing a small active region on the Sun, as you can see in this [3.1MB QT-mpeg4] movie. However, outside of the bright region, an even smaller structure provided some activity. Note the sudden "coronal dimming" as the small assemblage of magnetic arches rearranges its surroundings, reminiscent of much larger-scale dimmings associated with many coronal mass ejections. Courtesy of David McKenzie (MSU).
	This short movie, taken from TRACE observations on 2008/10/23 in the 171Å channel, shows two 'jets' inside the large coronal hole covering the solaar north-polar regions. Jets like these form when a small bipolar region emerges into a fairly uniform and nearly radial field inside the coronal hole - i.e., a sign of continued small-scale flux emergence at high latitudes even at times of cycle minimum. Courtesy of Steve Saar (SAO).
	With the Sun in a long-lasting sunspot minimum, only very few new-cycle regions show up. This region, AR 11005, was observed by TRACE in its 195Å (left) and visible-light (center) passbands on 2008/10/14 around 03 UT. The small spot and pores faded away by the end of 2008/10/16, although the coronal brightening endured. The 195Å image on the left is relatively dark on the southern side of the active region, particularly for the field emanating from the small spot group. This is consistent with a model field (based on the PFSS concept), shown in the image on the right: this image shows an open-field region (or coronal hole) associated with the spot group, with (black) field lines reaching into the solar ecliptic to form the interplanetary magnetic field. TRACE images courtesy of Aki Takeda and David McKenzie (MSU); full-Sun with PFSS ovelay from the LMSAL forecast site.
	Deep in its cycle minimum, the Sun still displays low-latitude coronal holes. This one, observed on 2008/09/30 at 05:45:01 UT in TRACE's 171Å channel, even touches on the equator in its northernmost reaches. Assimilation models show this region to be the result of several near-equatorial flux emergences near the equator early in 2008- some of that flux still remains near the equator because the meridional flow away from it is very slow. This coronal hole is likely associated with a fast wind stream in a period of otherwise unusually slow solar wind.
	Filaments involved in large coronal mass ejections can be a million kilometers long. And then there are the 'tiny' ones: this TRACE movie shows a short sequence of 12 frames (showing only 1/4 of the instrument's field of view) taken in the 171Å passband on 2008/07/21 from 15:20 UT to 15:36 UT (rotated counterclockwise by 90 degrees, with north to the left). Just to the left of the bright ephemeral region on the limb is a small filament eruption, showing as a rising dark loop. The separation of its footpoints as measured against the sky is a 'mere' 13000 km, i.e. about the diameter of the Earth, but some 75 times smaller than its largest cousins. Data set suggested by Paolo Grigis (SAO).
	With the Sun in a very low state of magnetic activity, there is ample opportunity to observe the quiet corona. This image, taken by TRACE on 2008/07/19 at 21:24:46 UT in its 195Å channel, shows the quiet solar limb. On the disk, we only see the coronal bright points overlying the ephemeral bipolar regions. High over the solar surface, the corona consists of a softly glowing haze, but above the limb, we see thin, nearly-vertical stalks. This reflects the fact that much of this field connects to distant regions on the Sun, if not to the heliosphere proper (compare with this PFSS field model, showing the magnetic field lines - white, closed; green, open to the heliosphere).
	The Sun has a cavity. This cavity, however, is not a sign of decay but of a region under a filament/prominence whose magnetic field is isolated from the rest of the corona. These regions may look like coronal holes when they are observed on the Solar disk, but the similarities are mostly superficial. Both coronal holes and cavities appear dim in comparison to the rest of the corona due to a density decrease in both regions. However, it has been shown that cavities are consistently 2-5 times denser than their coronal hole counterparts. Coronal holes are regions where magnetic field lines extend out into space allowing for plasma to stream away from the Sun. The, cool, dense, filaments that typically lie above cavities make the magnetic field in these regions quite complex and not well understood. The magnetic field and temperature structure of cavity regions may hold clues to the production and eruption of filaments. The TRACE observations (including this 171Å image taken on 2008/07/03 at 21:27:18 UT) are a part of a coordinated campaign that includes spectrometers, polarimeters used to measure magnetic fields, and other imagers. Each instrument provides different clues that help scientists understand how these features form and evolve. Courtesy of Henry (Trae) Winter, Montana State University, Solar Physics Group.
	Long after the discovery of the outflow of particles from the Sun, or solar wind, there is still much debate over its source. The solar wind is known to have regions of different speed and density, the so-called slow and fast solar wind. Data from the Ulysses spacecraft showed that the slow solar wind emanates from equatorial, closed magnetic field regions while the fast solar wind appears to emerge from the open magnetic field regions of coronal holes. The source and acceleration of the fast solar wind from these regions is still unclear. Polar plumes (long lived steady streams of plasma extending away from the Sun in the image) were initially thought to contribute to the fast solar wind, but it was discovered that the inter-plume boundaries are a more likely source, and the plumes themselves may contribute to the slow solar wind. Activity at coronal hole boundaries (bright regions around the coronal hole) is another candidate source for the fast wind. In these regions open field meets the closed field of the quiet Sun creating an environment for multiple areas of reconnection that could dump accelerated plasma out along the open magnetic field lines. Yet another possibility pointed to by recent observations is that jets (eruptions of fast, hot plasma triggered by reconnection -- one is seen as a bright dot just to the right and below the center of the image) are the source of fast solar wind. Their abundance in number, amount of mass and energy deposited, and location in open magnetic fields make them good candidates for fast solar wind production. Sorting among these possibilities will require more theoretical modeling and observations (e.g. with the soon to be launched Solar Dynamics Observatory). This image of the Sun's southern polar regions was taken by TRACE on 2008/06/28 at 00:00 UT in its 171Å channel. Courtesy Samaiyah Farid and Jonathan Slavin (SAO).
	By mid-summer of 2008, the Sun continues its rather long quiet state, characteristic of cycle minimum. In the absence of real active regions, the thousands of small, so-called ephemeral bipolar regions continue to maintain a minimal solar activity. These regions are everywhere embedded within the diffuse glow of the quiet corona, except over the polar caps, where they stand out brightly within the large coronal holes that cover these regions in this phase of the solar cycle. This image shows the ephemeral regions and their coronae over the solar North Pole on 2008/07709 at 04:58 UT observed by TRACE with its 195Å pass band. Image courtesy of Dawn Myers (at GSFC).
	With the Sun stubbornly remaining in a state of minimal activity, it offers ample opportunity to study the continued evolution of fields on the scale of ephemeral regions (upperleft) and the surrounding so-called quiet Sun. The quiet Sun regions contain a multitude of small magnetic bipoles and randomly walking flux concentrations, with loops off all lenght scales threading the corona above it. This image, taken by TRACE at 2008/06/05 18:05:29 UT in its 171Å channel, shows an area of quiet-Sun corona, full of small faint loops and darker areas where there is either little field, or where the field is more of one polarity leading to longer, fainter connections in the corona above it. Courtesy Dawn Myers (GSFC).