Solar Terrestrial Activity Report [Image] Last update June 17, 2001 at 05:55 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update June 3, 2001)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update June 4, 2001)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update June 4, 2001)] [Historical solar and geomagnetic data charts 1954-2001 (last update April 8, 2001)] Recent development The geomagnetic field was quiet to unsettled on June 16. Solar wind speed ranged between 283 and 347 km/sec. Solar flare activity was low. Solar flux was 207.6, the planetary A index was 7 (3-hour K indices: 2222 2332, Boulder K indices: 2221 2221). Regions 9491, 9492 and 9493 all decayed slowly and were quiet. Region 9495 was mostly unchanged. A minor M class flare is still possible. Region 9497 was spotless in all available images. Region 9498 decayed further and could become spotless within a couple of days. Region 9499 was quiet and stable, as was region 9500. Region 9501 appears to be developing and could soon become capable of producing C and minor M class flares. Region 9502 added a few more spots and still has M class flare potential. Region 9503 developed further and is capable of generating major flares. Region 9504 developed slowly and was quiet. An M class flare is possible. Region 9506 developed slowly and is a complex region capable of major flare production. Region 9507 emerged in the northeast quadrant. New region 9508 emerged near the southwest limb. Flares and CMEs A total of 8 C class events were recorded on June 16. Region 9495 produced a C1.9 flare at 07:08 UTC. Region 9505 generated a C3.9 flare at 19:!3 UTC, while region 9502 managed a C5.1 flare at 20:10 UTC. June 15: A full halo CME was observed beginning just before 16h UTC in LASCO C3 images. The source of this CME was most probably behind the southwest limb and may have been the source of the halo CME observed on June 14 as well. A moderate type II radio sweep was recorded coincident with the observation of the CME and a weak proton event began shortly afterwards. June 14: A full halo CME was observed in LASCO C3 images. The front of the CME first appeared at the west limb in LASCO C2 images at 10:30 UTC, fairly coincident with the above long duration C6.5 event in region 9489. LASCO EIT images are not conclusive as to whether the LDE was the source of the CME, however, there appears to be too little movement for what would have been a wide CME. The source of the CME may have been a backside event. The background x-ray flux is at the class C1 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to unsettled on June 17-18, possibly with isolated active intervals. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is fair to poor. Coronal holes (1) Coronal mass M and X class flares (3) ejections (2) [Coronal hole indicator][CME indicator] [M and X class flare indicator] 1) Effects from a coronal hole could reach earth within the next 5 days. 2) Material from a CME is likely to impact earth within 96 hours. 3) There is a possibility of either M or X class flares within the next 48 hours. Green: 0-20% probability, Yellow: 20-60% probability, Red: 60-100% probability. Active solar regions (Recent map) Solar Date Actual no. Location region numbered sunspots at Area Classification Comment midnight 9491 2001.06.05 1 N28W66 0110 HSX 9492 2001.06.06 1 N23W70 0020 AXX 9493 2001.06.06 1 N07W64 0080 HSX 9495 2001.06.08 9 N06W73 0290 DAO beta-gamma 9497 2001.06.10 2 S10W49 0020 BXO now spotless 9498 2001.06.10 4 N24W22 0040 CSO 9499 2001.06.11 1 N20W58 0060 HSX 9500 2001.06.11 7 N10E04 0040 CAO 9501 2001.06.11 7 S13E02 0090 CAO 9502 2001.06.12 19 S25E19 0110 DAO beta-gamma 9503 2001.06.13 35 N13E33 0420 FKC beta-gamma 9504 2001.06.13 7 N07E37 0410 CKO 9505 2001.06.14 2 N21E46 0100 DSO 9506 2001.06.14 17 N17E61 0720 FKI beta-gamma 9507 2001.06.15 2 N12E11 0030 CSO 9508 2001.06.16 1 S20W60 0010 AXX Total number of sunspots: 116 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 2000.03 208.2 138.5 119.9 (+3.1) 2000.04 184.2 125.5 120.8 (+0.9) cycle 23 sunspot max. 2000.05 184.9 121.6 119.0 (-1.8) 2000.06 179.8 124.9 118.7 (-0.3) 2000.07 202.3 170.1 119.7 (+1.0) 2000.08 163.0 130.5 118.6 (-1.1) 2000.09 182.1 109.7 116.2 (-2.4) 2000.10 167.4 99.4 114.5 (-1.7) 2000.11 178.8 106.8 112.8 (-1.7) 2000.12 173.6 104.4 (111.1 predicted, -1.7) 2001.01 166.6 95.6 (107.6 predicted, -3.5) 2001.02 146.6 80.6 (102.8 predicted, -4.8) 2001.03 177.7 113.5 (99.2 predicted, -3.6) 2001.04 177.7 108.2 (98.0 predicted, -1.2) 2001.05 147.1 97.3 (97.3 predicted, -0.7) 2001.06 167.0 (1) 104.8 (2) (94.6 predicted, -2.7) 1) Running average based on the daily 20:00 UT solar flux value at 2800 MHz. 2) Unofficial, accumulated value based on the Boulder (SEC/NOAA) sunspot number. The official international sunspot number is typically 25-40% less. This report has been prepared by Jan Alvestad. It is based partly on my own observations and interpretations, and partly on data from sources noted in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ Do you know about the survey which will be held this Summer among the listeners of WWV and WWVH? There is information about this survey at 16 minutes past the hour on WWV and at 47 minutes past the hour on WWVH. If you want to participate send an email with your name and address. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]