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Images of the Sun taken by the
Transition Region and Coronal Explorer

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.
Spot group in AR9690 in white light
Active region 9690 contained an interesting cluster of spots and pores. This (QuickTime/JPEG; 13.6MB) movie in white light shows its evolution from 8 November 2001 at 01:46 UT through 13 November at 6:17 UT. Projection effects make the region appear to expand and shrink as it crosses the solar central meridian. There are multiple occurrences of emerging flux, both in the center of the region and at the edge of the trailing spot group, which contains flux of both polarities (see the MDI magnetogram at sohowww or bbso).
TRACE mosaic
Yohkoh image
These images, taken on 8 February 2001, show how different the corona looks when observing emission from gas at 1 million Kelvin (top, TRACE 171Å, combining several pointings that were part of a full-disk mosaic) or at 2-5 million Kelvin (bottom, Yokhoh/SXT). The field of view is 700,000 by 350,000 km. Courtesy Bart De Pontieu.
X1.5 flare in AR9906 in 195Å
On 21 April 2002, TRACE observed an X1.5 flare in Active Region 9906 at the solar limb. The observations, at a high cadance in 195Å (a mixture of Fe XII at 1.5 million degrees and Fe XXIV at some 10 million degrees) show some remarkable features that have never been seen before this close to the Sun; they can be seen in this (QuickTime/JPEG; 15.8MB) movie (with images rotated so that north is to the left). Between 00:50 and 01:05UT there is a faint brightening that rapidly expands upwards. Then, for about 25 minutes, there is an unusually hazy, striated, rapidly-evolving pattern of emission visible above the active region. Around 01:33UT another new phenomenon is seen: dark blobs move downward into the bright haze. Some look as one might expect for dark, cool material sinking through a hot, tenuous material underneath, with some sign of vortices. The rest of the evolution is more familiar: bright flare ribbons leaving a bright trail of ``prairie fire'', and arcades of cooling loops form, with dark, cooled material draining back towards the solar surface.

This running-difference LASCO movie shows what appear to be similar infalling clouds, albeit at much greater heights (from LASCO web pages at NRL).

Eruption in AR9885 in 195Å
The (QuickTime/JPEG; 11.7MB) movie shows an eruption which came from Active Region 9885 on 9 April 2002. The images are rotated so that North is to the right. The movie and image are in the 195\Aring; (1.5 million degree) pass band. As the eruption begins, one can see some dark material lifting off and being blow out. Courtesy: Dawn Myers.
M1.2 flare and oscillations in AR9601 in 171Å
On 7 September 2001, TRACE observed this M1.2 flare in Active Region 9601. The (QuickTime/JPEG; 3.9MB) movie in 171Å (1 million degrees) - rotated so that north is to the left - shows a filament eruption near the bottom of the frame, and a bright loop arcade limbward of that. These two events, starting at the same time in brightenings of the low flare ribbons, are clearly related. Note that the loops high over the bright arcade quiver briefly after the flare - another one of those loop oscillations. And if you look closely, there are more loops oscillating ...
AR9611 in 171Å
On 12 September 2001, TRACE observed Active Region 9611 and surroundings at the NW limb of the Sun. The image to the right, and the (QuickTime/JPEG; 6.3 MB) movie in 171Å (with a field of view of 230,000 by 170,000 km) were rotated over +90 degrees, so that north is to the left.
The movie shows a variety of events, all occurring within a timespan of 5 hrs (see the annotated version to see the labels): A a cusp between the two loops systems on either side of the field of view, perhaps indicating a coronal neutral (or X) point where the field strength goes to zero; B a set of loops oscillating around 14UT; C another set of loops oscillating around 15:40UT; D a filament around the active region with multiple sprays of chromospheric material flowing around and within it; E a set of whirling loops tops around 14:30UT (we have no idea what is actually happening here); and coronal rain around 14:50UT.
Draining loops in AR9866 in 195Å
On March 12 2002, TRACE observed these cooling loops in Active Region 9866. The (QuickTime/JPEG; 1.1MB) movie 195Å shows the loops appear as they cool into the temperature domain visible with the TRACE filter used (around 1.5 million Kelvin) . Some time around 03:10 UT, dark clumps begin to appear, that slide down the magnetic field: that material is at temperatures below about 20,000 Kelvin, and dense enough to absorb the extreme ultraviolet radiation emitted by hot gas behind it. These loops may be associated with a C3.9 flare listed to have occurred around 02:24 UT by NOAA without AR indication. The movie is shown at half the resolution, with a field of view of 290,000 km square. Courtesy: Dawn Myers.
Long cool loop in AR9871
On 19 March 2002, around 06 UT, TRACE observed long, cool loops in the interior of Active Region 9871. The structure persisted for several hours, although the movie suggests that not always the same field lines lit up. The distance between the footpoints of the long, thin thread is 230,000 km. The true loop length is hard to estimate, because we do not know its height.
Eruption in AR 9871
New magnetic field emerging onto the solar surface on 20 March 2002 near Active Region 9871 led to an interesting eruption. The newly emerged field interacts with the pre-existing field, mostly associated with a sunspot in AR9871. The result is an ejection of mass (and a spray or surge of cool, dark material somewhat later), that starts just before 14UT. Bright, hot material (seen in this Quicktime/JPEG; 3.6MB movie taken in the 171Å passband, mostly sensitive to emission from plasma around 1 million degrees) is thrown upward with projected speeds of some 500 km/s. What is interesting in this case, is that it appears that the field is twisting as it rearranges. But we see material move only in one direction relative to the ejection. We are still thinking about how to interpret this phenomenon. The field of view of is 240,000 by 280,000 km; the images were taken with 2x2 on-chip binning.
Filament eruption in AR9841
On 26 February 2002, TRACE observed a filament eruption in Active Region 9841 near the edge of the solar disk. The set of 6 images (rotated over +90 degrees) show the evolution of the cool, chromospheric material as it is being lifted up to a height of 60,000 km. Most of the material then slides back to the surface along the changing magnetic field. The process takes just over an hour, after which a set of cooling loops is seen to form over the site of the filament destabilization.

Other TRACE images in this collection: Set 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14.

See also a collection of images related to the Sun, other cool stars, and solar-terrestrial effects


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