10 Jan 2014 coronal hole observation


For this observation I requested the large format EIS raster ISSI_jet_1 to be run on the coronal hole. My request to IRIS was to run a small format raster on a specific bright point.

Of additional interest is a filament eruption that came from the quiet Sun just adjacent to the coronal hole on the south east side of the EIS raster. It can be seen between about 22:00 and 23:30 in the AIA 193 movie. I don't see any high velocity features in the 22:18 and 23:17 EIS rasters, though.

EIS observation

Eleven repeats of ISSI_jet_1 were scheduled beginning at 18:24 and finishing at 05:09 UT. A movie showing intensity and velocity images from the sequence is available below (if the embedded movie doesn't work, try clicking on the link below it.

EIS intensity-velocity movie (0.9 MB)

There are no interesting velocity events in this sequence, but the image sequences show a nice jet structure in the 03:12 and 04:10 rasters, coming from a bright point at (190,660).

AIA observations

The movie below shows the evolution of the EIS FOV as seen in the AIA 193 filter, at 1min cadence. If the embedded movie does not work, try clicking on the link below it.

AIA 193 movie (log intensity, 1min cadence, 13 MB)

IRIS observations

I requested that IRIS point at the most intense bright point within the EIS FOV (see image below). I also asked for the bright point to be placed at the bottom of the slit.

The bright point was still present at the start of the observation although it was fainter. As with the 21-Dec-2013, the IRIS pointing drifted eastward during the observation period.

IRIS was in its eclipse season, so the observation consisted of six distinct observation periods. The following links go to Javascript movies for each of the five periods, showing 1400 slitjaw movies (these movies are held at LMSAL).

Movie 1, 18:19-19:04 UT
Movie 2, 20:00-20:44 UT
Movie 3, 21:34-22:19 UT
Movie 4, 23:10-23:54 UT
Movie 5, 00:50-01:34 UT
Movie 6, 02:24-03:13 UT

A jet can be seen in Movie 2 in the period 20:23 to 20:28 in the middle of the slit. There should be some spectra for this event. The jet is seen by AIA, about 40" north of the target IRIS BP. It's quite a faint jet. By comparing the slitjaw images with the spectra, it looks like the exposure at 20:28:02 contains the leg of the jet. A brightening is seen in Si IV, and the line seems to be broad and redshifted.

Another jet is seen in Movie 6 near the top of the slit. It occurs between 02:55 and 03:10. There are two parts: an initial helical shaped feature, followed by something that looks almost flare ribbons. Again there should be good spectra for this event. AIA sees this event at position (275,690) at 03:00,