Sector & corrotation

The upper chart (sector structure) is based on ACE MAG real time data of recent 27 days. The chart is divided into 27 pieces surrounded by the ideal Archimedes spirals. 1-day averages of the Bx and By components in the GSE coordinate system are used to color the chart. Every day around 0UT we rotate the chart by 1/27*360 degrees and color one piece of the chart based on yesterday's ACE data. We tried other averages (for example 1-hour, 3-hour, and ...) to make this chart, but we found it was best to use 1-day averages to recognize sector boundaries.

[ACE RTSW Sector & Corotation]