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Each month a summary of sunspot activity is written and forms part of a report sent to the Solar Section of the British Astronomical Association (BAA) and to The Astronomer. Follow the links below to read a page summary of sunspot activity. The McIntosh Sunspot Group Classification is used for sunspot group descriptions.
On the 1st and 2nd only 4 groups were seen. One of these was a high latitude F type group at 37°N/11° that had an area of 160 millionths on the 1st. Another group, at 9°N/307°, was the return of a Fkc group seen between the 2nd and 10th December; now it had decayed into a Dsc group with a much reduced area of 110 millionths when seen on the 2nd. 3 additional groups had developed on the disk by the 4th but all were small in size. The most interesting and largest group of the month was seen close to the eastern limb on the 9th as an Ehc group. On the 10th, the following spot was seen to be quite asymmetrical and was the largest spot of the group - two smaller symmetrical spots were seen leading this spot. By the 14th, the group, at 12°S/175°, had developed into a collection of following asymmetrical penumbral spots spread out in latitude together with a single asymmetrical spot leading. On this date, the longitudinal extent of the group was such that it was classified as type Dac when the total area was estimated at 360 millionths. The appearance of the penumbral spots had changed by the 15th and again by the 16th together with a reduction in area. By the 17th, the penumbral spots had again reduced in size but not in number. This group had been seen on the previous two rotations; between the 18th and 28th November and between the 19th and 23rd December. On the 14th, a total of 12 groups were seen when R had a value of 195. One of these groups was an Hsx spot near the eastern limb at 19°N/117°; this spot was all that remained of the impressive Fhc group seen between the 19th and 28th December. During the period between the 14th and 24th its largest area was only 190 millionths on the 16th. On the 17th and 21st some accompanying spots were seen. Another group at 17°S/131° and near the eastern limb on the 14th was also seen during the previous rotation; then it was a single Hho spot while it was now a smaller Dso group. When seen on the 17th, the group had developed to become type Eac and then into type Esc on the 21st with an area of 210 millionths. As the group neared the western limb on the 23rd and 24th, only an Hsx spot was seen. The number of groups seen peaked at 13 on the 16th and then gradually decreased to 6 on the last observation of the month on the 29th when only one group was seen in the northern hemisphere.
The modest activity seen during January continued into February. On the 2nd the largest of the 7 groups seen was a Dsc group at 27° N/291° with an area of 100 millionths. The southern hemisphere included high and low latitude groups at -35°/223° and -8°/311° (both Hsx spots). The next two observations on the 5th and 11th showed increased activity with 9 and 10 groups respectively but the size of all the groups remained small. On the 12th, 13th and 16th activity in the southern hemisphere continued to dominate. With excellent seeing conditions on the 16th, a total of 14 groups were seen; all but two of these were in the southern hemisphere and half of these were either of type Axx or Bxo. Also on the 16th a Dso group at 21°S/118° was seen near the meridian - it comprised of several small penumbral spots and other spots. When this group was next seen on the 20th, it had developed into a Fac group with 6 irregularly shaped penumbral spots arranged in no obvious east-west orientation. The total area of the group had grown from 60 to 560 millionths between the 16th and 20th. By the 21st the apparent size of the group had reduced since it was nearing the western limb but the following spot had grown in size to give the group a Fkc classification. The group was last seen on the 22nd. The observation made on the 20th showed a single Hhx spot at 22°N/20° with an area of 260 millionths. The appearance of this group remained the same on the 21st and 22nd but by the 25th it had developed a following penumbral spot together with other smaller following spots. This following penumbral spot was seen to decay by the 26th and it had disappeared completely by the 28th when the group was near the western limb. The 21st saw a small Cso group near the eastern limb. By the following day, several penumbral spots had developed. By the 25th the group had grown again into a Dkc group with asymmetrical leading and following penumbral spots together with small penumbral and other spots between. Now the group had an area of 520 millionths as it was at a mean location of 15°S/331°. On the 26th, the following spot had increased in size again and it had engulfed two penumbral spots seen the previous day to give a group with just the leading and following penumbral spots. A light bridge was seen within the following spot. On the 28th, the following spot had increased in size further and it appeared to be joined to the leading spot. The total area of the group was now 910 millionths although the group remained type Dkc. A light bridge was again seen in the following part of the group. On the 25th and 26th a large irregularly shaped group of type Ekc was seen close to the eastern limb at 15°S/278°. It covered some 8° in latitude and it comprised of one main irregular penumbral spot with several umbra embedded within it and a few following small penumbral spots. By the 28th, the effects of foreshortening had reduced to show the group better; it had an area of 890 millionths. This group and the previously mentioned Dkc group were both easily visible with the protected naked eye on this date.
The two moderately sized groups seen at the end of February were still prominent during the early part of the month. The western of these groups, at 16°S/329° and of type Dkc, had reduced slightly in size on the 1st to 830 millionths. It still comprised one main irregular penumbral spot with several umbra within it. This group was also seen on the 3rd and 4th as it neared the western limb. On the 3rd, the main penumbral spot appeared to split into two spots and into several penumbral spots by the 4th. The other modest spot, at 13° S/277° and type Ekc, had grown to just over 1000 millionths by the 1st where the majority of the growth had been in the dominant leading penumbral spot. The spot was irregular and its latitude and longitude extents were similar. A number of smaller penumbral spots were seen following and to the south of the main spot. The appearance of the main spot changed again by the 3rd (when the group had just passed the central meridian). The area of the group has reduced to 780 millionths on the 4th when the northern part of the main spot began to separate from the rest of the spot. This separation had occurred by the 5th when the longitudinal extent of the group had reduced such that the group was now of type Dkc. The group had disappeared around the limb by the time of the next observation on the 12th. On the 12th, the majority of the activity was in the southern hemisphere with 9 groups compared to just 2 in the north. One of these southern groups was of type Dki at 15°S/123° with an area of 970 millionths; it comprised one main irregular elongated spot of 8° extent in longitude which included several penumbra and a light bridge towards the northern part of the spot. By the 15th the main spot had split into an irregular leading penumbra spot and two following penumbral spots; the total area had reduced to 790 millionths. The decay of this group continued as it neared the western limb and the group was last seen on the 19th. From the 18th, activity in the northern hemisphere began to increase. One of the 3 groups seen was a collection of numerous small penumbral spots in the form of a Dac group at 13° N/70° (this group had been seen on the 15th as a two penumbral spot group of type Dai). The size of the some of the penumbral spots had increased by the following day, the 19th, and the group became type Ekc. On the 21st, the leading penumbral spot had become the largest of the group. Although the number of spots within the group had reduced, its total area had increased to 820 millionths. By the 22nd, this group, now nearing the western limb, comprised two irregular penumbral spots and a small number of surrounding spots. The number of groups seen on the 25th and 26th had increased substantially compared to other March observations. Although no group was especially large (the largest being a Dkc group at 17° S/320° with an area of 370 millionths), the groups were spread out in longitude across the disk and there were almost equal in number between the northern and southern hemispheres. The appearance of the Sun on these two dates was fairly typical of solar maximum activity.
The observation on the 1st showed a total of 16 groups with an almost equal number in the northern and southern hemispheres and across the disk. None of these groups were particularly large but included were a Dsc group at 16°N/267° with an area of 60 millionths and a Dac group at 13°S/267° with an area of 90 millionths. Both of these groups were seen again towards the end of the month, as described below, when they had developed into much larger groups. On the 6th, the number of groups seen had reduced to 11 with just 3 in the northern hemisphere. Up to the 10th, southern hemisphere continued to dominate activity. During this period, one of the most interesting groups was of type Dac at 14°S/130°. This comprised, on the 8th for example, of 6 small penumbral spots with no obvious east-west alignment together with numerous spots. The total group area on this date was 160 millionths. The appearance of this group was similar on the 9th and 10th although the number of penumbral spots had reduced slightly. The observations on the 18th and 19th showed a mixture of group types amongst the 9 groups seen on each date. These ranged from single Axx spots to an Eao group at 21°S/32° with an area of 310 millionths. The 21st showed two large groups on the eastern limb, with one in each hemisphere. The northern of these, at 18°N/265°, comprised primarily of a pair of penumbral spots with the following spot being the larger and irregular and the leading spot being fairly symmetrical. This group was classified as type Eko. By the 23rd, it became more obvious that the following penumbral spot was quite irregular which included a light bridge. The area of the group on this date was estimated to be 780 millionths while it was re-classified as type Ekc due to the presence of other penumbral spots. On the following day, the 24th, more small penumbral spots were seen surrounding the following spots and the total area of the group had increased to 930 millionths. Subsequent observations on the 27th and 29th showed a slightly smaller group with fewer spots between the leading spot (which changed little throughout) and the more symmetrical following spot. The other large group seen on the 21st, at 14°S/263°, was first seen as an irregular leading spot containing a prominent umbra and a collection of following penumbral spots. The appearance of this leading spot changed from observation to observation in terms of its exact shape and arrangement of umbra within it. In addition, the following spots changed shape and number during the group's passage across the disk. The total area of the group was estimated to be 1050 millionths on the 23rd, 1170 millionths on the 24th, 1080 millionths on the 27th before it reduced to 740 millionths on the 29th - this group was probably the largest seen so far this solar cycle. Activity on the last observation of the month, on the 29th, was concentrated on the western portion of the disk with 7 groups seen: only a small Hsx spot was seen in the eastern hemisphere.
The two moderately sized groups seen at the end of April were seen nearing the western limb on the 1st. The northern group, at 18°N/261°, was of type Ekc with an area of 740 millionths while the southern group, at 13°S/263° was of type Dkc with an area of 660 millionths. Of the 7 groups seen on this date, only two were in the eastern hemisphere. Daily observations between the 4th and 8th showed considerably reduced activity in terms of the number of groups and more particularly of the size of the groups seen. For example, on the 6th four groups were seen where the largest, at 24°N/100° and type Cao, had an area of only 50 millionths. The western of three groups seen in the north east quadrant on the 8th had increased in size from 90 to 220 millionths by the following day. This group, at 17°N/82° and of type Dkc, grow further by the 11th (330 millionths) and 13th (470 millionths) when it was seen as an irregularly shaped leading spot with several smaller penumbral spots following and to the south of the main spot. Another of the north eastern groups from the 8th, at 14°N/63°, had also increased in size by the 11th when it was also of type Dkc and comprised a slightly asymmetric leading spot and several following penumbral spots. By the 14th, the total area of this group was 400 millionths; the leading spot had increased in size to become asymmetric in the east-west direction. Both of these groups decayed as they progressed towards the western limb. The largest group of the month was first seen near the eastern limb on the 11th as three highly foreshortened penumbral spots. By the 13th, the group, at 20°S/345° and type Eko, was seen to comprise two equally sized irregular spots. On the 14th, these two spots appeared to merge which included many umbra, the largest being in the leading part of the group. The area of the group on this date was estimated to be 1310 millionths. When seen on the 15th and 16th, the group consisted of several penumbral irregular spots without significantly reducing in size and being classified as type Ekc. The next observation, on the 20th, showed a more compact and symmetrical group with a reduced total area of 1050 millionths. The group continued to decay as it neared the western limb such that it had an area of only 310 millionths when seen on the 22nd. During its passage across the disk this group had another smaller group following and slightly to the north at 12°S/333° . This group was at its largest on the 20th with an area of 480 millionths when it was of type Dac. On the 14th, a single penumbral spot was seen on the eastern limb at 19°N/308°. When it had rotated more onto the disk on the 15th it could be seen to be of type Ekc. By the 20th when the group was nearing the central meridian the leading spot was quite symmetric with smaller penumbral spots following together with many other spots between to give a total area of 700 millionths. To the south of this group was a Dko group at 11°N/316° which consisted primarily as an elongated irregular spot with an almost north/south orientation and an area of 460 millionths. On this date, the 20th, a total of 4 spots were seen with the protected naked eye. By the 22nd both groups had reduced in size with the penumbra of the Dko group splitting into two. These groups were last seen on the 27th and 25th respectively. Activity reduced again during the latter part of the month when all but one of the groups was small in size. The exception was first seen on the limb on the 25th at 12°S/175° and of type Eko. When seen on the 29th, it comprised two slightly asymmetric spots at either end of the group together with a string of spots between. The leading spot was the larger of the two penumbral spots and the total area was estimated to be 630 millionths on this date. The group straddled the central meridian on the 31st when only a total of 6 groups were seen. Interestingly, activity between the 27th and 31st included three groups with latitudes within 5° of the equator.
The Eko group at 12°S/170° seen at the end of May was still the most prominent group on the 1st; the leading spot was quite asymmetrical with a reasonably large umbra and the total area was 500 millionths. As this group neared the western limb the number of intermediate spots decreased and the following spots decayed such that on the 4th, the group just consisted of the leading penumbral spot and a few other spots. A single Hsx spot was seen near the limb on the 6th. Also on the 1st, an Eko group was seen near the eastern limb. On the 3rd and 4th, it could be seen that it consisted of a leading irregular penumbral spot and a following symmetrical spot with other smaller penumbral spots between. By the 6th, this group, at 21°N/75° had increased in area to 700 millionths caused by the increase in area of both the leading and following spots. The main spot was still quite irregular with many umbra within. By the 8th, the main spot had decayed into four smaller penumbral spots with the following spot now being the largest in the group and the total group area had dropped to 370 millionths. As this group progressed towards the western limb, the leading set of penumbral spots reduced in number and size; on the 12th only the following penumbral spot remained. This Hsx spot was seen returning to the visible disk on the 30th. The next significant group was first seen on the 6th and was again in the northern hemisphere. On the 7th, with the group at 23°N/17°, it was seen as type Eao but on the following day it had extended to become type Fkc with an irregular leading spot. This spot increased in size over the next couple of days to dominate the group when seen on the 10th. On the following day, the leading spot became more symmetrical and numerous other spots, some of which included small penumbral spots, followed it. The total group area was 480 millionths. The leading spot became smaller on the 12th and this continued as the group neared the western limb. Just 2 small penumbral spots were seen on the 17th. Two other moderately sized groups were towards the eastern limb on the 15th at 21°N/284° and 20°N/254°. The first of these reached maximum area on the 16th and 17th at 520 millionths when the group had a classification of Ekc. It appearance was of an irregularly shaped leading spot and two close by following penumbral spots with, especially on the 17th, many spots between. When the group straddled the central meridian on the 19th, the leading spot was still dominant while the following spot had decayed. When the group was last seen on the 21st it was of type Dac with an area of 280 millionths. The other eastern group from the 15th was much more compact and consisted of larger individual penumbral spots and it was of type Dkc. On the 18th, when the total area was at its greatest at 600 millionths, there were two penumbral spots with the leading being the largest. The following part of this spot had separated when seen on the 19th. On the 20th and 21st, the following spots decayed slightly to leave a group dominated by the still asymmetrical leading spot. Only a single Hsx spot was seen near the western limb on the 27th.
The observation on the 2nd showed an equal distribution of groups between the northern and southern hemispheres with 6 each. The largest of these was a Cai group at 14°S/119° with an area of 180 millionths. The next observation on the 7th showed a complex Eac group at 18°N/32° that was near the central meridian with an area of 370 millionths. Four southern groups were seen at similar latitudes and approximately evenly separated in longitude. These were at 19°S/63° (type Hax), 17°S/47° (Dac), 16°S/30° (Csi) and 18°S/15° (Dac). By the 11th, the western most group was near the limb and the other three groups appeared to give the impression of a string of spots stretching for some 60° in longitude. The 11th also showed two northern Fkc type groups. One was at 18°N/34° with an area of 500 millionths while the other was at 19°N/314° with an area of 740 millionths. The latter group was the more impressive with a large symmetrical following spot with several small leading penumbral spots. When this group was seen on the 13th, the following spot had decayed while the number of spots within the group had increased substantially; its area was now 500 millionths. By the 17th, the group had decayed further such that its total area was only 270 millionths and it was of type Dac. Observations made each day between the 17th and 22nd inclusive showed very high levels of activity that were the highest seen during this cycle so far. The highest activity day was the 19th when 17 groups were seen almost equally distributed between the northern and southern hemispheres, the sunspot number was 279 and the quality parameter, Q, was 54! The largest group on this date was an Eac group at 10°S/235° with 530 millionths. This group was particularly interesting as it had no obvious bipolar structure - it consisted of many penumbral and other spots spread over almost 15° in longitude and unusually over 11° in latitude. Even more spots were seen within this group on the 20th. Some of the penumbral spots appeared slightly larger on the 21st although the number of spots had reduced slightly. The group had a similar appearance on the 22nd. Another interesting group during this period was first seen on the 19th having just rotated onto the disk as a Dhc group at the low latitude of 7°N/170° . On the 20th, it comprised a single very elongated asymmetrical penumbral spot with a couple of adjacent spots. When seen on the 21st, the main spot had split into three and its total area was 610 millionths and it was of type Ekc. By the 22nd, four penumbral spots were now seen with the leading one still being the largest.
The first observation of the month, on the 9th, showed an Eac group just passed the central meridian at 9°N/334° . The largest spot of this group was an asymmetrical penumbral spot located towards the centre of the group. When seen on the 11th, the group appeared more compact as some of the following small penumbral spots had disappeared, while 4 small penumbral spots had appeared just to the south. The group had a similar appearance on the 12th when its total area was 420 millionths - this was the largest group seen during the month. The group was last seen on the 13th as it neared the western limb. Between the 9th and 13th, a high latitude Dso group was seen at 32°S/325° which consisted of just two equally sized penumbral spots with a total area of 90 millionths. Another high latitude group was first seen on the 11th at the even higher latitude of 37°S/270° as a Dso group. On the 12th, this group had decayed to type Cso and it was not seen on the 13th. However, unusually the group reappeared on the 15th as a Dao group with an area of 110 millionth. By the 19th, just a single Hsx spot was seen. Several low latitude groups were also seen. For example, between the 13th and 24th, a Hax spot was seen at 4°S/205° which attained a maximum area of 150 millionths on the 21st. On the 11th, a small Dso group was seen at 25°N/237°. By the following day, the number of spots within this group increased substantially and by the 13th, a number of these had developed into small penumbral spots. When the group was seen on the 15th, the penumbral spots had increased in area to give a total area of 210 millionths and a classification of type Dac. Subsequent observations between the 19th and 22nd showed the group gradually decaying such that on the 22nd only a Bxo group was seen near the western limb. Activity between the 15th and 19th decreased from 12 to 9 groups and the majority of these were in the western hemisphere. This meant that activity continued to reduce with only 5 group being seen on the 22nd. The largest group seen on this date was a Dai group at 8°S/150° with an area of 150 millionths. Activity then increased slowly. By the 28th, for example, 10 groups were seen and the largest 2 groups were both of type Eac at 26°N/90° with an area of 220 millionths and at 17°S/47° with an area of 210 millionths.
The moderate activity seen at the end of August continued into the early part of the month. On the 2nd, the largest of the 12 groups seen was an Ekc type at 14°N/357° and near the central meridian with an area of 370 millionths. The size of the leading spot had reduced on the 3rd so the group became type Eac with a reduced area of 260 millionths. When seen on the 6th, the group consisted of a collection of penumbral spots surrounding the main near symmetrical leading spot. The only other moderate group seen during this early part of the month was first seen on the 4th at 17°S/329° as a Dac group with an area of 130 millionths (no group was seen at this location on the previous day). The group had many small spots and pores following a quite asymmetrical leading penumbral spot. When next seen on the 6th a string of penumbral spots were seen following an enlarged and symmetrical leading spot. The total area was now 330 millionths. By the 9th, the group neared the western limb with a similar appearance and it was last seen on the 10th. The number and size of all groups seen in the eastern part of the disk on the 6th were small. As the disk rotated no further moderately sized groups appeared - indeed the number of groups reduced such that on the 11th only one Hsx spot was seen. On the 12th 3 groups were seen, all having formed on the disk since the previous day while on the 14th, 4 groups were seen with 3 having small penumbral spots. The next observation on the 20th showed a marked change in activity with the appearance of a large Fkc group at 11°N/81° and towards the eastern limb. It comprised of one irregular main spot with many umbra within it and many following small penumbral spots. The group had a total area was 2040 millionths to make it the largest group of this solar cycle so far. This group was first seen at the same position on the disk one rotation earlier as an Hrx spot on the 23rd August. On the 21st, the total area remained almost the same while the shape of the main spot changed slightly. By the 22nd, the size of the umbra within the main spot had increased and regions of photosphere could be seen within the main spot. A finger of penumbra had appeared stretching from the leading part of the main spot. As the group neared the central meridian on the 23rd and 24th, it appeared larger although the total area had reduced slightly to 1960 millionths on both dates. When seen on the 23rd, a larger region of photosphere could be seen just following the leading umbra spot together with a string of photosphere across the following part of the main spot. There were still many surrounding small penumbral and other spots around the main spot, especially in the following direction. By the 24th, the finger of penumbra seen on the previous 2 days had separated to form two penumbral spots. Also on this date, the size of the photosphere regions in the following part of the main spot had increased. Indeed on the 25th, this part of the main spot started to split and it was completely separate on the 26th. The total area of the group reduced to 1460 millionths on the 25th and further to 1310 millionths on the 26th; the number of surrounding spots had also reduced on these two dates. Another spot was seen with the protected naked eye on the 20th; this being a Dkc group at 12°S/126° . On the 21st it obtained its maximum area of 730 millionths when it comprised of an irregular main spot which had an extent of almost 7° in both latitude and longitude. By the next day this spot had decayed into two such that they were at almost the same longitude. Further decay could be seen on the 23rd and 24th when there were many penumbral spots but now the total area had reduced to 400 millionths. This group was seen nearing the western limb on the 25th and 26th.
The largest of the 8 groups seen on the 1st was of type Ehc at 8°S/322° with an area of 360 millionths. The leading spot of this group dominated as all the following spots were small. When next seen on the 5th, the group had reduced in size to 200 millionths and it had lost all the following penumbral spots to become type Csi. It had a similar appearance on the 6th but by the 8th several penumbral spots could be seen near the western limb. The group with the longest longitudinal extent on the 1st was also in the southern hemisphere. This was of type Eac at 11°S/353° with an area of 270 millionths. By the 5th, the group was seen approaching the western limb and it was last seen on the 6th. The only other moderately sized group from the 1st was a Dac group with an area of 150 millionths at 20°S/315° and thus to the south of the Ehc group. By the 5th, the group had grown into an Eac group with an area of 240 millionths before decaying such that on the 8th only a single penumbral spot near the western limb was seen. On the 5th a low latitude Eso group was seen at 3°N/247° with an area of 200 millionths. By the 6th, the following penumbral spot had disappeared while the number of spots following had increased to form a Csi group with a reduced area of 130 millionths. When last seen on the 8th, it had lost some of the following spots to become type Cso with an area of 110 millionths. The next observation on the 15th had a predominance of southern hemisphere groups but all were small in size; the largest was a Dac group at 10°S/130° with an area of 130 millionths. Near the eastern limb a Hsx spot was seen at 13°N/87° surrounded by an extensive area of faculae - this was the remnant of the large group seen in September. On the 26th all but one of the 6 group seen was in the eastern hemisphere but, once again, none were particularly large. One of these groups was the return of the Dac group seen on the 1st, now being type Dsc at 22°S/308°. On the 29th and 31st this group had an area of 180 and 190 millionths respectively and was of type Dac on both dates. Another low latitude group was seen on the 29th and 31st at 3°N/272° of type Hax and Hkx respectively and with an area of 210 millionths on the 31st.
There was an almost even distribution of groups between the northern and southern hemispheres on the 1st and 2nd. Included amongst these was the low latitude Hkx spot at 4°N/273° seen during the latter part of October. On the 2nd it had an area of 210 millionths which reduced slightly to 180 millionths on the 4th. Also seen on the 1st was a Dac group at 21°N/250° with an area of 120 millionths. By the 2nd, it had almost doubled in size to 220 millionths through the leading and following penumbral spots. These spots continued to grow as did the longitudinal extent of the group to become type Eao with an area of 270 millionths on the 4th. When next seen on the 10th, only a single Hsx spot was visible near the eastern limb. From the 10th to 13th, the number of groups dropped from 11 to just 6. The largest of these was of type Eac at 11°S/145° with an area of 200 millionths on the 10th. By the 12th, the leading spot appeared larger while the following penumbral spot reduced in size. Indeed, when seen on the 13th, no following penumbral spot was seen to make the group of type Cki; the leading spot had grown and had become asymmetrical with a total area of 240 millionths. By the next day, a small following penumbral spot could be seen once again. On the 15th, the number of following spot reduced while the leading spot was still quite asymmetric. This group was last seen on the 17th and 18th as an Hsx spot towards the western limb. On the 13th, a Dao group was seen on the eastern limb at 22°S/62°. When this had rotated further onto the disk on the 14th and 15th, many spots could be seen within the group. By the 17th, the group was of type Fac with a total area of 330 millionths; the group was seen to comprise of 24 spots in all with many small penumbral spots in the leading and following portions of the group. On the 18th, the leading part of the group was on the central meridian and the longitudinal extent was some 18° with 30 spots seen. On the 24th, the group was close to the western limb with a much reduced spot count. A Dso group seen on the eastern limb on the 18th had developed into an Hkx group at 21°N/359° by the 24th with an area of 490 millionths. It was now near the central meridian and there were many umbra within the spot including three at the leading edge of the penumbra, a main central umbra with a string of umbra following it. Several spots were seen surrounding the main spot, especially towards the north. The appearance of this group had changed again by the 26th when it was of type Dko with a slightly larger area of 540 millionths. Now the main penumbral spot was quite irregular and it had a different distribution of umbra within it. One of the now fewer accompanying spots had a small penumbra.
On the 3rd, the majority of the 13 groups seen were in the western hemisphere with an almost equal split between the north and south. The largest of the groups seen was of type Dao at 20°N/281° with an area of 400 millionths. This group consisted of a leading slightly asymmetrical penumbral spot with several small following penumbral spots. Only two other groups had moderately sized penumbral spots - a Hsx spot at 10°N/301° and a Cai group at 10°S/253° which had an area of 90 millionths. All the remaining groups either had small penumbral spots or were of type Axx or Bxo. The next observation on the 9th showed a reduced number of groups. Amongst these was a Csi group at 11°N/165° with an area of 60 millionths (which was an Axx spot on the 3rd) and an Eac group near the eastern limb at 14°N/88°. The region around this latter group had developed substantially by the 14th as 3 groups could be seen; these were of types Bxo at 17°N/84°, Dai at 14°N/91° with an area of 60 millionths and Dac at 8°N/85° with an area of 170 millionths. Thus, it was the southern most of these that was the largest and it comprised an asymmetric leading penumbral spot which had several umbra and it was followed by a collection of small penumbral and other spots. When seen on the 15th, the number of spots had reduced but the size of the following penumbral spots had increased to give a total area of 260 millionths. However, by the 16th, the group reduced in size to 120 millionths through a reduction in the size of all the penumbral spots. Another moderately sized group seen on the 14th was of type Dac at 21°S/67°. It consisted of an irregular arrangement of penumbral spots spread out both in latitude and longitude but none were especially large as the total group area was just 260 millionths. On the subsequent 2 days, the number of penumbral spots reduced to 3 and consequently the area reduced to 150 millionths on the 16th. The next observation was not until the 28th. The most impressive of the 10 groups seen was near the eastern limb at 7°S/202° and type Ekc. It comprised a slightly asymmetrical leading penumbral spot which appeared some 4° in latitude and included several umbra together with a string of small following penumbral spots. By the 29th, the leading penumbral spot became quite asymmetric with several spots now appearing around it; the following penumbral spots had coalesced into two irregular spots. The corrected total group area was estimated to be 1010 millionths on this date. When this group was last seen on the 30th, the leading spot had changed shape again while the following spots had increased to 3 and each of these included several umbra. The number of smaller spots within the group had also increased. The group area was a slightly reduced 970 millionths.
Last updated on 08 February 2004. |
