(Week 34, 1998)
The SXT instrument is working well. Solar activity was pretty high towards the end of the week with a number of M-class flares and several X-class flares. The Whole Sun Fortnight campaign continued this week with coverage of a number of active regions (AR8303, AR8304 AR8307) and the southern extension of the north polar coronal hole. AR8303 is a small active region but bounded the coronal hole on its NE side. AR8307 rotated around the E limb during this reporting period and produced a number of large flares, including an X4 flare (see below). Details can be obtained from ISAS or GSFC. See the weekly operations report for details. The GOES level has been quite dynamic as AR8307 rotated around the E limb. As usual, the GOES time series for the week is shown below. Click it for enlargement.
In the display above (click to enlarge), the colored lines show the times of SXT images that currently are on-line at ISAS. The purple lines are flare mode. The gaps will be considerably reduced when the NASA telemetry arrives and gets reformatted. For a summary index listing of the weekly science reports, click here.
This week saw several X-flares from active region AR8307 as it rotated around the East limb. On eof the largest was an X4 flare which occurred on 16-Aug-98 at 22:20 UT. Yohkoh cuaght the rise phase, peak and much of the decay of this large flare.
Associated with this flare was a significant reconfiguration of the surrounding active region corona as demonstrated by the following movie.
