IHOP 267 observations of AR 12178 (Oct. 2014)

This AR had a small sunspot that passed the central meridian around 0 UT on 3-Oct-2015. Three observations were obtained as part of IHOP 267.

There was a problem with the EIS planning tool at this time which led to offsets between the requested pointing and the actual pointing. The pointings are about 30-40" north of where they should be so the sunspot appears at the bottom of the EIS rasters.

2 October

IRIS: 11:16-14:46, 21 rasters
EIS: 23:06-02:40, 31 rasters

There was a mix-up this day and EIS and IRIS ended up observing at different times!

3 October

Sunspot position: (+156,-132) at 23:11 UT
IRIS: 23:04-03:03, 24 rasters
EIS: 23:06-02:40, 30 rasters

This is a good observation for which the IRIS and EIS rasters have good overlap and the sunspot plumes are centered in the rasters. The movie below shows an AIA 171 image sequence for the duration of the observation. The broad plume on the right of the image remains stable for the observation

AIA 171 movie at 1 minute cadence. Logarithmic intensity scaling.

The images below are from the movie sequence, but showing snapshots from the beginning, middle and end of the sequence, showing how the large scale topology changes with time.

Below I show some IRIS and EIS quicklook images (obtained through the raster_browser routines) from 02:40 UT showing a good correspondence between the O IV features in the two instruments. The IRIS plot show continuum (left) and O IV 1401 (right). The EIS plot shows O IV 279.94 (left), Mg VI 269.0 (middle) and Fe IX 197.86 (right). All images are shown with a logarithmic scaling. Note that the EIS field-of-view is larger than IRIS and the left-hand brightening is not seen by IRIS.