HELIOS no. 60        02.May. 2000

This Helios Newsletter continues a series newsletters under the same name as above and that were issued as the newsletter of the Solar Section of the Norwegian Astronomical Society.  Helios no. 1 was issued on 2nd May 1979 and ended almost simultaneously as I resigned as the leader of that section, i.e. in August 1989.   Now I bring it to life again, started where I left it. 
Comments?   Post them!

Quiet Geomagnetic Conditions

From SESC/PRF 1286

Prepared by the U.S. Dept. of Commerce, NOAA, Space Environment Center


Solar Proton Events Affecting the Earth Environment

January 1976 - February 18, 2000
================================================================================================
-------------PARTICLE EVENT---------- ASSOCIATED ---------FLARE AND ACTIVE REGION---------
Start Maximum Proton Flux CME Flare Max. Importance Location Region#
(Day/UT) (pfu @ >10 MeV) (Loc./ Day UT)(Xray/Opt.) (SWO)
-----------------------------------------------------------------------------------------------

1976
Apr 30/2120 May 01/1700 12 Apr 30/2114 X2/2B S09W47 700

1977
Sep 19/1430 Sep 19/2130 200 Sep 19/1054 X2/3B N08W58 889
Nov 22/1400 Nov 22/1800 160 Nov 22/1006 X1/2N N24W38 939

1978
Feb 13/0930 Feb 14/1000 850 Feb 13/0255 M7/0B N22W13 1001
Apr 11/1530 Apr 11/1630 65 Apr 11/1353 X2/2B N19W54 1057
Apr 29/0445 Apr 30/2000 1,000 Apr 28/1306 X5/4B N22E41 1092
May 07/0420 May 07/0420 100 May 07/0330 X2/2B N22W64 1095
Jun 02/0730 Jun 02/0935 19 May 31/1009 M5/2B N23W50 1129
Jun 24/0900 Jun 25/0230 25 Jun 22/1709 M2/3B N19E18 1164
Jul 13/0300 Jul 13/1000 20

Sep 23/1035 Sep 24/0400 2,200 Sep 23/1023 X1/3B N35W50 1294
Nov 10/2130 Nov 10/2140 38 Nov 10/0042 M1/2N N17E02 1385

1979
Feb 17/2020 Feb 17/2205 31 Feb 16/0200 X2/2B N15E48 1574
Apr 03/1600 Apr 03/2310 45
Jun 06/1850 Jun 07/0005 950 Jun 05/0529 X2/1N N20E16 1781
Jul 07/0015 Jul 07/1010 50
Aug 19/0850 Aug 21/0740 500 Aug 18/1416 X6/1B N10E90 1943
Sep 15/1500 Sep 16/1200 60 Sep 14/0802 X2/ N10E90 1994
Nov 16/0430 Nov 16/1300 75 Nov 15/1639 M1/0B N34W25 2110

1980
Feb 06/1340 Feb 06/1850 12
Jul 17/2300 Jul 19/1930 100 Jul 17/0603 M3/1B S12E06 2562

1981
Mar 30/0900 Mar 30/2115 30 Mar 30/0049 M3/2N N13W74 2993
Apr 10/1745 Apr 11/1400 50 Apr 10/1655 X2/3B N09W40 3025
Apr 24/1515 Apr 24/2330 160 Apr 24/1400 X5/2B N18W50 3049
May 09/1200 May 10/2130 150 May 08/2252 M7/2B N09E37 3099
May 15/0300 May 16/1950 130 May 13/0425 X1/3B N11E58 3106
Jul 20/1430 Jul 20/1825 100 Jul 20/1329 M5/1B S26W75 3204
Jul 25/0600 Jul 25/1320 18
Aug 10/0115 Aug/10 0435 57 Aug 07/1916 M4/2B S10E24 3257
Oct 08/1235 Oct 13/2247 2,000 Oct 07/2308 X3/1B S19E88 3390
Dec 10/0545 Dec 11/0900 65 Dec 09/1854 M5/3B N12W16 3496

1982
Jan 31/0055 Jan 31/1630 830 Jan 30/2358 X1/3B S13E19 3576
Jun 06/0245 Jun 06/0245 10 Jun 03/1146 X8/2B S09E72 3763
Jun 09/0040 Jun 09/0510 30 Jun 06/1637 X12/3B S11E26 3763
Jul 11/0700 Jul 13/1615 2,900 Jul 09/0742 X9/3B N17E73 3804
Jul 22/2030 Jul 23/0220 240 Jul 22/1734 M4/0F N29W86 3804
Sep 05/2205 Sep 06/0100 66 Sep 04/0400 M4/3N N11E30 3886
Nov 22/1940 Nov 22/2140 40 Nov 22/1828 M7/1N S11W43 3994
Nov 26/0605 Nov 26/1500 25 Nov 26/0253 X4/2B S11W87 3994
Dec 08/0010 Dec 08/1000 1,000 Dec 07/2354 X2/0B S14W81 4007
Dec 17/1845 Dec 18/0945 130 Dec 15/0202 X12/2B S10E24 4026
Dec 19/1920 Dec 20/0515 85 Dec 19/1624 M9/2B N10W75 4022
Dec 27/0600 Dec 27/1345 190 Dec 25/0752 X2/1B S14E31 4033

1983
Feb 03/1200 Feb 04/1620 340 Feb 03/0619 X4/3B S19W08 4077
Jun 15/0435 Jun 15/1800 18 Jun 14 S09W90 4201

1984
Feb 16/0915 Feb 16/1005 660 Feb 16 S12W90 4408
Feb 19/1310 Feb 21/1415 55 Feb 17/2301 X2/2B
N16E82 4421
Mar 13/1440 Mar 13/1450 10
Mar 14/0405 Mar 14/0505 100 Mar 14/0334 M2/2B S12W42 4433
Apr 25/1330 Apr 26/1420 2,500 Apr 25/0005 X13/3B S12E43 4474
May 24/1045 May 24/1140 31 May 22/1503 M6/2B S09E24 4492
May 31/1315 May 31/1415 15 May 31/1142 M1 S09W90 4492

1985
Jan 22/0415 Jan 22/0550 14 Jan 21/2350 X4/2B S08W38 4617
Apr 25/1430 Apr 26/0600 160 Apr 24/0935 X1/3B N06E27 4647
Jul 09/0235 Jul 09/0325 140 Jul 09/0204 M2/1B S16W36 4671

1986
Feb 06/0925 Feb 07/1730 130 Feb 06/0625 X1/3B S04W06 4711
Feb 14/1155 Feb 15/0400 130 Feb 14/0929 M6/1B N01W76 4713
Mar 06/1835 Mar 06/1930 21 Mar 06/1703 C4/1F N02E01 4717
May 04/1255 May 04/1320 16 May 04/1007 M1 N06W90 4717

1987
Nov 08/0200 Nov 08/0940 120 Nov 07/2014 M1 N31W90 4875

1988
Jan 02/2325 Jan 03/0835 92 Jan 02/2145 X1/3B S34W18 4912
Mar 25/2225 Mar 25/2330 58 Mar 25/2145 EPL N22W90 4965
Jun 30/1055 Jun 30/1140 21 Jun 30/0906 M9/2B S16E22 5060
Aug 26/0000 Aug 26/0045 42 Aug 23/1804 M2/EPL N24E90 5125
Oct 12/0920 Oct 12/0930 12 Oct 12/0511 X2/2N S20W66 5175
Nov 08/2225 Nov 09/0635 13 Nov 07/1105 M3/1N S17W47 5212
Nov 14/0130 Nov 14/0235 13 Nov 13/2309 M3/1N S23W27 5227
Dec 17/0610 Dec 17/0855 18 Dec 15/0505 X1/1N N27E59 5278
Dec 17/2000 Dec 18/0150 29 Dec 16/0841 X4/1B N26E37 5278

1989
Jan 04/2305 Jan 05/0130 28 Jan 04/1753 M4/1N S20W60 5303
Mar 08/1735 Mar 13/0645 3,500 Mar 06/1405 X15/3B N35E69 5395
Mar 17/1855 Mar 18/0920 2,000 Mar 17/1744 X6/2B N33W60 5395
Mar 23/2040 Mar 24/0110 53 Mar 23/1948 X1/3B N18W28 5409
Apr 11/1435 Apr 12/0125 450 Apr 09/0105 X3/4B N35E29 5441
May 05/0905 May 05/1000 27 May 04/1115 M5/2N S20W36 5464
May 06/0235 May 06/1045 110 May 05/0737 X2/3B N30E01 5470
May 23/1135 May 23/1350 68
May 24/0730 May 24/0905 15 May 22/0037 M5/2B S21E16 5497
Jun 18/1650 Jun 18/1910 18 Jun 18/1447 C4/0F N12W31 5534
Jun 30/0655 Jun 30/0710 17 Jun 29/2127 M3/2B N26W60 5555
Jul 01/0655 Jul 01/0720 17
Jul 25/0900 Jul 25/1225 54 Jul 25/0844 X2/2N N25W84 5603
Aug 12/1600 Aug 13/0710 9,200 Aug 12/1427 X2/2B S16W37 5629
Sep 04/0120 Sep 04/0510 44 Sep 03/1432 X1/1B S18E16 5669
Sep 12/1935 Sep 13/0825 57 Sep 12/0814 M5/EPL S18W79 5669
Sep 29/1205 Sep 30/0210 4,500 Sep 29/1133 X9/EPL S26W90 5698
Oct 06/0050 Oct 06/0825 22
Oct 19/1305 Oct 20/1600 40,000 Oct 19/1258 X13/4B S27E10 5747
Nov 09/0240 Nov 09/0610 43
Nov 15/0735 Nov 15/0910 71 Nov 15/0659 X3/3B N11W26 5786
Nov 27/2000 Nov 28/1105 380 Nov 25/2355 X1/2N N30E05 5800
Nov 30/1345 Dec 01/1340 7,300 Nov 30/1229 X2/3B N26W59 5800

1990
Mar 19/0705 Mar 19/2315 950 Mar 19/0508 X1/2B N31W43 5969
Mar 29/0915 Mar 29/1005 16 Mar 28/0751 M4/2N S04W37 5988
Apr 07/2240 Apr 08/1330 18 Apr 04/1338 M7/0N N22E72 6007
Apr 11/2120 Apr 11/2130 13
Apr 17/0500 Apr 17/0655 12 Apr 15/0302 X1/2B N32E57 6022
Apr 28/1005 Apr 28/1735 150
May 21/2355 May 22/0750 410 May 21/2219 X5/2B N35W36 6063
May 24/2125 May 25/0115 180 May 24/2051 X9/1B N33W78 6063
May 28/0715 May 29/0100 45
Jun 12/1140 Jun 12/1700 79 Jun 12/0541 M6/2B N10W33 6089
Jul 26/1720 Jul 26/2315 21
Aug 01/0005 Aug 01/2015 230 Jul 30/0736 M4/2B N20E45 6180

1991
Jan 31/1130 Jan 31/1620 240 Jan 31/0230 X1/2B S17W35 6469
Feb 25/1210 Feb 25/1305 13 Feb 25/0819 X1/2N S16W80 6497
Mar 23/0820 Mar 24/0350 43,000 Mar 22/2247 X9/3B S26E28 6555
Mar 29/2120 Mar 30/0330 20
Apr 03/0815 Apr 04/1000 52 Apr 02/2327 M6/3B N14W00 6562
May 13/0300 May 13/0910 350 May 13/0144 M8 S09W90 6615
May 31/1225 Jun 01/0445 22
Jun 04/0820 Jun 11/1420 3,000 Jun 04/0352 X12/3B N30E70 6659
Jun 14/2340 Jun 15/1950 1,400 Jun 15/0821 X12/3B N33W69 6659
Jun 30/0755 Jul 02/1010 110 Jun 28/0626 M6 N30E85 6703
Jul 07/0455 Jul 08/1645 2,300 Jul 07/0223 X1/2B N26E03 6703
Jul 11/0240 Jul 11/0450 30 Jul 10/1228 M3/2N S22E34 6718
Jul 11/2255 Jul 12/0205 14
Aug 26/1740 Aug 27/1830 240 Aug 25/0115 X2/2B N25E64 6805
Oct 01/1740 Oct 01/1810 12 Sep 29/1533 M7/4B S21E32 6853
Oct 28/1300 Oct 28/1440 40 Oct 27/0548 X6/3B S13E15 6891
Oct 30/0745 Oct 30/0810 94 Oct 30/0634 X2/3B S08W25 6891

1992
Feb 07/0645 Feb 07/1115 78 Feb 06/1048 M4/2B S13W10 7042
Mar 16/0840 Mar 16/0840 10 Mar 15/0154 M7/3B S14E29 7100
May 09/1005 May 09/2100 4,600 May 08/1546 M7/4B S26E08 7154
Jun 25/2045 Jun 26/0610 390 Jun 25/2014 X3/2B N09W67 7205
Aug 06/1145 Aug 06/1210 14 Aug 03/0706 M4/1N S09E68 7248
Oct 30/1920 Oct 31/0710 2,700 Oct 30/1816 X1/2B S22W61 7321

1993
Mar 04/1505 Mar 04/1735 17 Mar 04/1240 C8/2N S14W56 7434
Mar 12/2010 Mar 13/0155 44 Mar 12/1815 M7/3B S00W51 7440

1994
Feb 20/0300 Feb 21/0900 10,000 Feb 20/0141 M4/3B N09W02 7671
Oct 20/0030 Oct 20/0340 35 Oct 19/2127 M3/1F N12W24 7790

1995
Oct 20/0825 Oct 20/1210 63 Oct 20/0607 M1/0F S09W55 7912
1996

1997
Nov 04/0830 Nov 04/1120 72 W/04 0610 Nov 04/0558 X2/2B S14W33 8100
Nov 06/1305 Nov 07/0255 490 W/06 >1300 Nov 06/1155 X9/2B S18W63 8100

1998
Apr 20/1400 Apr 21/1205 1,700 W/20 1007 Apr 20/1021 M1/EPL S43W90 8194
May 02/1420 May 02/1650 150 Halo/02 1406 May 02/1342 X1/3B S15W15 8210
May 06/0845 May 06/0945 210 W/06 0829 May 06/0809 X2/1N S11W65 8210
Aug 24/2355 Aug 26/1055 670 NA Aug 24/2212 X1/3B N30E07 8307
Sep 25/0010 Sep 25/0130 44 NA Sep 23/0713 M7/3B N18E09 8340
Sep 30/1520 Oct 01/0025 1,200 NA Sep 30/1350 M2/2N N23W81 8340
Nov 08/0245 Nov 08/0300 11 ?

Nov 14/0810 Nov 14/1240 310 NA Nov 14/0518 C1/BSL N28W90 8375?

1999
Jan 23/1105 Jan 23/1135 14 NA Jan 20/2004 M5 N27E90
Apr 24/1804 Apr 25/0055 32 Halo/24 1331 NW limb 8517?
May 05/1820 May 05/1955 14 Halo/ 03 0606 May 03/0602 M4/2N N15E32 8525
Jun 02/0245 Jun 02/1010 48 Halo/ 01 <1937 Jun 01/~1930
Jun 04/0925 Jun 04/1055 64 NW/ 04 0726 Jun 04/0703 M3/2B N17W69 8552

2000
Feb 18/1130 Feb 18/1215 13 W/ 18 0954 Feb 17/2035 M1/2N S29E07 8872
===============================================================================================

Text Box: Please Note: Proton fluxes are integral 5-minute averages for
energies > 10 MeV, given in Particle Flux Units (pfu), measured by GOES
spacecraft at Geosynchronous orbit: 1 pfu = 1 p/sq. cm-s-sr. SWO defines the
start of a proton event to be the first of 3 consecutive data points with
fluxes greater than or equal to 10 pfu. The end of an event is the last time
the flux was greater than or equal to 10 pfu. This definition, motivated by
SWO customer needs, allows multiple proton flares and/or interplanetary
shock proton increases to occur within one SWO proton event. Additional data
may be necessary to more completely resolve any individual proton event.

Different detectors, onboard various GOES spacecraft, have taken the data
since 1976. These proton data were processed using various algorithms. To
date, no attempt has been made to cross-normalize the resulting proton
fluxes. Flare associations are given, although data about individual Coronal
Mass Ejections (CMEs), available from SOHO since 1996 on

***

Solar Proton Events Affecting the Earth Environment

January 1976 - February 18, 2000


    SUM     4     55      66

                C      M     X
    1976     0    0    1
    1977    0    0    2
    1978     0    4    4
    1979     0    1      4
    1980     0    1      0
    1981     0    5      4
    1982     0    4      8
    1983     0    0    1
    1984     0    3      2
    1985     0    1      2
    1986     1     2      1
    1987     0    1      0
    1988     0    4      4
    1989     1     5      13
    1990     0    4      4
    1991     0    5      9
    1992     0    4      2
    1993     1     1      0
    1994     0    2      0
    1995     0    1      0
    1996     0    0    0
    1997     0    0    2
    1998     1     3      3
    1999     0    3    0
    2000     0    1      0

Extracts from Preliminary Report and Forecast, SEL, Boulder, CO. USA:


SWO PRF 1277 22 February 2000
14 - 20 Feb 2000
Solar activity ranged from low to moderate levels. Region 8869 (S20, L = 118, class/area Eai/300 on
20 February), was the most active region, producing multiple C and M-class events. The largest being
an M2/1B accompanied by a Type II radio sweep on 17/1852UT. Region 8872 (S29, L = 093,
class/area Bxo/020 on 17 February) produced a long duration M1/1N on 17/2035UT. This event also
produced a Type II radio sweep, a 200 SFU Tenflare, and a Full-halo CME. This was thought to be a
sympathetic flare due to its close proximity to Region 8896. The rest of the regions during the period
were mostly quiet and of simple magnetic classification.

***

SWO PRF 1278 29 February 2000
21 - 27 February 2000
Solar activity varied from low to moderate levels. Region 8869 (S23, L = 116, class/area Fai/520 on 21
February) produced isolated, low-level M-class flares on 21 - 22 February during a period of gradual
growth. This region departed the visible disk on 23 February. Activity decreased to mostly low levels
during 23 - 25 February with an optically uncorrelated M1 X-ray flare at 24/0111UT. Activity
increased to moderate levels on 26 February with an M1/2F parallel-ribbon flare at 26/2352UT from
Region 8889 (N21, L = 290, class/area Fso/370 on 26 February). Activity dropped to low levels on the
final day of the period as Region 8882 (S15, L = 328, class/area Ekc/800 on 27 February) produced
numerous C-class subflares.

***

SWO PRF 1279 07 March 2000
28 February - 05 March 2000
Solar activity varied from low to high levels. Activity was low during 28 February - 01March with
occasional C-class flares. Activity rose to high levels on 02 March due to a pair of major flares from
Region 8882 (S16, L = 328, class/area Ekc/1100 on 02 March). The first was an impulsive X1/2B at
02/0828UT with associated Type II and IV radio sweeps. The second was an impulsive M6/SN at
02/1343UT with an associated Type II sweep and a 290 SFU Tenflare. Region 8882 showed increased
magnetic complexity prior to the major flare occurrences, but began to slowly decay thereafter. Region
8886 (S14, L = 344, class/area Dso/070 on 29 February) produced an isolated M1/1F flare at
2/0841UT during a period of minor growth. Activity declined to moderate levels on 03 March as
Region 8882 (which continued to slowly decay) produced an M3/1B flare at 03/0214UT accompanied
by a 240 SFU Tenflare and a Type IV radio sweep. Region 8886 produced an M4/SN flare at
03/1046UT as it crossed the west limb. Activity decreased to low levels during the remainder of the
period.

***

SWO PRF 1280 14 March 2000
06 - 12 March 2000
Solar activity varied from low to moderate levels. Activity was low during 06, 09, and 10 March with
occasional C-class flares. Activity was moderate on 07 March due to an M1/1F event at 07/1950UT
from an unnumbered region near S22 on the east limb. An optically uncorrelated M1 flare also
occurred at 07/1607UT. Activity was again moderate on 08 March due to an impulsive, optically
uncorrelated M1 flare that occurred at 08/0200UT. On 11 March, activity was moderate due to an
M1/1N event at 11/0927UT from Region 8906 (S16, L = 122, class/area Dkc/800 on 11 March).
Activity was also moderate on 12 March with an M3/1B event occurring at 12/2338UT from region
8906. Region 8906 was the most impressive region during the period. The region showed rapid growth
and increased activity toward the end of the period becoming an Fkc group with 41 spots, measuring
850 millionths, and a beta-delta magnetic classification by March 12th.

***

SWO PRF 1281 21 March 2000
13 - 19 March 2000
Solar activity was predominantly moderate for the week. A total of seven low-level M-class events
was observed. Region 8906 (S16, L=122, class area EKC/900 on 14 March) was responsible for six
of those M-class flares. This region exhibited significant magnetic complexity, including several delta
configurations, during the period. Region 8910 (N12, L=071, class/area EKC/590 on 19 March) was
responsible for the other M-class event. This region grew at a moderate pace during the period and
developed a delta configuration at the end of the period. Many coronal mass ejections occurred during
the week. None appeared to be Earth directed.

***

SWO PRF 1282 28 March 2000
14-20 March 2000
Solar activity ranged from low to high levels. Region 8910 (N11, L = 069, class/area Ekc/810 on 22
March) produced two impulsive major flares during the period: an X1/2N at 22/1848UT with
associated Type II and IV radio sweeps and a 500 SFU Tenflare, and an X1/2B at 24/0752UT with
associated Type II and IV radio sweeps and a 570 SFU Tenflare. Region 8910 was large and
magnetically complex, but gradually decaying at the time these flares occurred. This region crossed the
west limb on 25 March. Solar activity was at moderate levels during most of the rest of the period due
to isolated low-level M-class flares (see the Energetic Event Summary for event times and associated
phenomena). M-flare contributors included Regions 8910, 8926 (S10, L = 013, class/area
Dso/090 on 26 March) and 8928 (N19, L = 282, class/area Cso/060 on 26 March).

***

SWO PRF 1283 04 April 2000
27 March - 02 April 2000
Solar activity ranged from low to high levels. The period began with activity at moderate levels as
Region 8926 (S10, L = 013, class/area Dai/090 on 24 March) produced isolated M-class flares which
included an M1/1N at 27/0518UT and an M3/SF at 28/0137UT. An optically uncorrelated Type II
radio sweep occurred at 27/0646UT. Activity dropped to low levels on 29 March with occasional C-class
x-ray flares, most of which were optically uncorrelated. Activity returned to moderate levels on
30 March as Region 8936 (S15, L = 202, class/area Dai/360 on 02 April) produced multiple low-level
M-class flares, which included an M1/SF at 30/1245UT, an M3/1N at 30/1606UT, and an M2/2B at
30/2325UT. Activity rose to high levels on 31 March due to numerous M-class flares from several
regions. The most flare productive of these was Region 8939 (N23, L = 194, class/area Dao/120 on 02
April), a small, compact region with a strong degree of magnetic mixing. It produced an M4/SF at
31/1019UT associated with a Type IV radio sweep, as well as M1/SF flares at 31/0755UT,
31/1318UT, and 31/1655UT. Region 8936, a compact, mixed-polarity group, showed moderate
growth during 31 March and produced an M1/SN at 31/0652UT. Region 8925 (S18, L = 283,
class/area Dki/270 on 27 March) added to the 31 March M-class total with an M2/1N at 31/1901UT.
Activity decreased to low levels during the last two days of the period with most regions either
stabilized or decaying.

***

SWO PRF 1284 11 April 2000
03 - 09 April 2000
Solar activity ranged from low to moderate levels. The period began with activity at low levels on 03
April. Region 8948 (S15, L = 130, class/area Eai/160 on 09 April) produced isolated M-class flares
which included an optically uncorrelated M1 flare on 04 April. The location was verified by using EIT
images from the SOHO spacecraft. Region 8933 (N17, L = 267, class/area Eko/420 on 04 April)
produced a C9/2F event on 04/1541UT. This event was accompanied by a Disappearing Solar
Filament (DSF) and a Coronal Mass Ejection (CME) that produced geomagnetic storming later in the
period. Solar activity was low on 05 April and moderate on 06 April due to an M1/2B event at
06/0229UT from Region 8948. Activity was low on 07 April and moderate for the last two days of
the period. Region 8948 produced isolated M-class events during that time, an M2/1B on 08/0240UT,
an M1/1N on 08/2046UT and an M1/1N on 09/0416UT. Region 8948 was by far the most active
region during the period, becoming 52-spot Eai group with a Gamma-Delta magnetic classification on
09 April.

***

SWO PRF 1285 18 April 2000
10 - 16 April 2000
Solar activity ranged from low to moderate levels. The period began with activity at low levels then
increased to moderate levels from 11-12 April. Region 8948 (S15, L = 129, class/area Eai/110 on 11
April) produced three M1-class flares during this period. Region 8948 showed steady decline in activity
after 12 April. Activity was low 13-14 April. Region 8948 did produce a C7, long duration, parallel-ribbon
flare, with a small filament disappearance on 13/2130UT. Activity level returned to moderate on
15 April as Region 8955 (S22, L = 031, class/area Eao/350 on 15 April) began to show a gradual
increase in magnetic complexity. Region 8955 produced an M4/SF on 15/1018UT, with an associated
570 SFU Tenflare and a partial-halo Coronal Mass Ejection (CME). Region 8955 also produced an
M2/1N on 15/1448UT and a C7/1N with a small filament disappearance on 15/1905UT. Solar activity
was low for the remainder of the period. Region 8955 had appeared to stabilize by the end of the
period.

***

************************************************************************************

There are 5 New members since 01. Feb. 2000:

We wish you all welcome!

Helios no. 61 will be issued 01. Aug. 2000

CV-Helios Network 02 mai 2000