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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.
The two northern hemisphere E type groups seen on 28th December were still on the disk on the 1st although one of the groups was just a single Hsx spot very close to the western limb. The other group had increased in size to 880 millionths and was of type Ekc (at 26°N/172°). The leading spot of this group was symmetrical in shape and was followed by several irregularly shaped penumbral spots. This group had decayed slightly when seen on the 2nd and it was last seen on the 4th when very near the western limb. The number of spots within the southern Dai type group seen on 28th December had reduced by the 1st such that the group was of type Cso (at 22°S/158°). Although the leading symmetrical leading spot remained the same size, the following spots had disappeared by the 4th. The next penumbral group was first seen as an Axx spot on the 1st, a Bxo group on the 2nd and then a Dao group on the 4th at 15°N/91° and with an area of 90 millionths. By the 5th, when the group was near the central meridian, the following penumbral spot became the largest of the group. The longitudinal extent of the group then extended such that on the 6th the group was of type Eso. It now had an area of 150 millionths. This group was last seen on the 8th when it was still of the same type even though the number of spots seen between the leading and following spots had reduced to only 1. The observation made on the 11th showed reduced activity with only 4 groups and of these only 2 had penumbra (both small Hsx spots). By the 17th activity had increased to give an R of 130 and a total of 6 groups. The most significant of these were a Fac group at 20°N/266° and an Eao group at 22°S/272°. The northern of these groups comprised of two equally sized leading and following penumbral spots together with a large number of penumbral and non-penumbral spots between. The total area of the group was only 200 millionths. This increased to 340 millionths by the 22nd when the group was of type Fkc. The southern group was quite small on the 17th at 130 millionths but this had increased to 500 millionths on the 22nd when the group was of type Eac. The leading spot of this group was quite asymmetrical and most of the following spots had penumbra. Both of these groups were last seen on the 23rd as they approached the western limb. The other groups seen on the 17th were a Hsx spot at 11°N/306° (area 60 millionths), a Dao group at 25°N/297° (area also 60 millionths) and two Bxo groups at 36°S/358° and 31°S/313°. Both of the penumbral spots groups were close to the western limb on the 21st. Only the Hsx spot was seen on the 22nd. The two Bxo groups were only seen on the 17th. On the 21st, a Dso group was seen near the central meridian having formed on the disk some time after the 17th. Its largest area was seen on the 21st at 80 millionths. It was still on the disk on the 23rd, the last observation of the month.
The first observation of the month, on the 7th, showed only 4 small groups. However, the next observation on the 13th showed a total of 10 groups and an R value of 177. Two of these groups were of naked eye size - these were at 15ºN/277º and 22ºS/272º and just to the east of the central meridian. The northern of these groups was a fine bipolar group of type Ekc with a total area of 580 millionths split almost equally between leading and following penumbral spots. The southern group also had an area of 580 millionths but almost of this was in the form of one large penumbral spot. An adjacent penumbral spot determined that the group was of type Dko. Both of these groups were seen during the pervious solar rotation in the third week of January. All but one of the other groups seen on the 13th contained penumbral spots but the largest of these was only 110 millionths. By the 20th, the large northern group was close to the western limb and consisted of just the leading and following penumbral spots. The large southern group changed slightly into a Hkx penumbral spot and was also near the western limb. The other 6 groups seen on this date were all small in size. The number of groups seen had reduced further by the 23rd when only 5 small group were seen. One of these, a small Cso group, was seen at the relatively high latitude of 30ºN/99º. By the 27th, this group had evolved into a Dao group with an area of 110 millionths. Also on the date, two other groups were seen at a similar high latitude: 30ºN/76º and 33ºN/61º but both were of types Bxo and Axx respectively. By the next day, both of these groups were of type Cso. All the other groups seen on this date were small in size.
The observation on the 10th, the first of the month, showed just 4 modestly sized groups. The only northern group, at 22ºN/275º and near the eastern limb, was of type Eac with the following spot being the largest. The total area of the group on this date was 140 millionths. The two small leading penumbral spots seen on the 12th had formed a single asymmetrical penumbral spot by the 13th - this spot contained several umbra and it was of similar size to the following spot (also asymmetric). This leading spot had grown further by the 14th - this together with the formation of several penumbral spots between the leading and following penumbral spots gave the group a classification of Fkc and an area of 580 millionths. On subsequent days the intermediate penumbral spots grew in size and were quite asymmetrical. When last seen on the 18th, the group was of type Fhc and very close to the western limb. The second largest group seen during the month was first seen on the 12th at 16ºN/239º and was of type Cao and near the eastern limb. By the 14th, the group was of type Dsc with an area of 200 millionths - the leading spot was symmetrical and was followed by several smaller penumbral spots. The group was slightly longer in longitude by the 16th to become type Esc with an area of 210 millionths (it was also near the central meridian on this date). Subsequent observations showed the group decaying such that it was of type Hax on the 20th and it was last seen near the western limb on the 22nd of type Hsx. The only other group seen with an area greater than 100 millionths was in the southern hemisphere at 26ºS/229º on the 18th when it has an area of 120 millionths. This group was first seen as type Bxo on the 14th, type Cso on the 16th, 17th and 20th before being of type Hax on the 21st and an Axx group on the 22nd. The highest number of groups seen on any day was 8 on the 20th, but all of these were small in area. After this date, the number of groups seen reduced to only 3 on the 23rd and 25th and then to just 2 on the 27th before increasing again to 6 on the 31st. Surprisingly for this stage in the solar cycle, the various indices of white light activity indicate that activity has been fairly constant since last October.
The two southern groups seen on the 1st were at similar latitudes and were separated by almost 20º in longitude. These groups were of types Hrx at 26ºS/10º and Cso at 27ºS/352º. Although the westward of these groups was not seen on the 2nd, a small Dai group had developed by the 4th. By the 6th, this group was of type Esc with a total area of 310 millionths - this was the largest group seen during the month. The leading spot of this group was symmetrical in shape and only this spot was seen on the 9th when it was very close to the western limb. The eastward group was of type Dso on the 4th when it had an area of 100 millionths before it decayed into type Csi on the 6th - it was not seen on the 8th. On the 4th a small Dso group was seen near the eastern limb at 18ºN/287º. By the 6th the largest spot had become asymmetrical in shape but by the 8th an irregularly shaped following spot had developed which had a latitude extent of some 4º. The group on this date was of type Ekc and it had an area of 190 millionths. By the 19th, this following penumbral spot had decayed such that both the leading and following spots were of similar size and both were asymmetrical. When next seen on the 12th, the group had decayed into type Dsi with an area of only 40 millionths. Only an Axx spot was visible on the 14th. Between the 12th and 16th, four small groups were seen reasonably close together: at 26ºS/245º, 33ºS/232º, 17ºS/234º and 18ºS/222º. The largest area measured for any of these groups was only 90 millionths. By the 17th a Hhx spot had appeared around the eastern limb at 14ºS/109º. It was still of type H on the 18th but by the 19th, following penumbral spots had appeared to change the group into type Dac when it had an area of 120 millionths. The following spots had reduced in number by the 22nd and this decay continued such that only a group of type Hax was seen on the 27th. On the 25th a Dso group was seen at 22ºN/33º while a Dao group was seen nearby at 18ºN/35º. The northern of these was of type Eac on the 27th and it had an area of 190 millionths. The southern group was of type Dso and smaller with an area of 50 millionths. By the time of the next observation on the 30th, both groups appear to have merged to give a group with a latitude extent of 8º and longitude extent of 14º. A string of spots was seen between the leading spot and the southern most penumbral spot. The largest spot was an asymmetrical following spot. The total area of the group was now 290 millionths.
The largest of the 4 groups seen on the 1st was of type Fsc at 18ºN/301º which, on the 2nd, had an area of 310 millionths. The appearance of this group changed little over the next two days but it then lost most of the following spots by the 6th and all of them by the 8th. In the period up to the 8th all the southern groups seen during this period were either Axx or Bxo types. The number of groups than increased, especially in the eastern part of the disk such that by the 8th a total of 12 groups were seen with R having a value of 181. On the 6th a Hho spot was seen near the eastern limb at 20ºN/217º. As this group progressed across the disk it was of type Hkx with a main spot and a few accompanying small spots. It obtained a maximum area of 370 millionths on the 15th. The group was last seen near the western limb on the 17th. Some 25º following was, on the 8th, an Esc group at 20ºN/193º. By the 12th the number of penumbral spots had increased and on the 15th and 16th the group became type Fac. However, the maximum area seen was only 210 millionths on the 16th. On the 14th another isolated H type group appeared around the eastern limb - this time at the moderately high latitude of 35ºN/102º. As the group progressed towards the central meridian it became asymmetrical in shape and it was accompanied by a few small spots. On the last observation of the month, on the 22nd, it had just past the central meridian. During the month 2 low latitude groups were seen. The first of these was seen during the period 6th to 11th at 3ºN/227º. On the 8th, this group was of type Dso but it then decayed into type Axx on the 9th. The second group was seen between the 12th and 16th at 6ºN/150º and it was of type Axx.
On the 1st, 3 of the 10 groups seen were of moderate size: an Esi group at 19ºN/343º with an area of 410 millionths which comprised of similarly sized leading and following penumbral spots with a few small spots between; a Dac group at 16ºS/291º with an area of 300 millionths which comprised an asymmetrical leading spot and numerous small following penumbral spots; a Dsc group at 14ºN/284º with an area of 550 millionths which comprised a leading symmetrical spot, two similar sized following spots together with other smaller penumbral spots. By the 5th only the following spot of the first group was seen - this being close to the western limb. The second group had developed a larger following spot while the leading spot had become quite asymmetrical - also the number of penumbral spots had reduced considerably although the total area had increased to 420 millionths. The third group almost halved in size while being of a similar structure. The later two groups were last seen on the 8th and 9th respectively. Also on the 5th, 3 small northern hemisphere groups were seen near the eastern limb. The number of groups in this general area increased to 4 on the 6th and to 5 by the 8th. The northern most of these was of type Dai at 30ºN/208º with an area of 200 millionths. Just to the south was an Axx spot at 20ºN/204º and a Cso group at 19ºN/191º (area 40 millionths). All of these groups had developed by the 10th such that they were of types Eac (still with an area of 200 millionths), Dsc (area 70 millionths) and Eai (area 190 millionths). By the 13th, the northern group had decayed into a Dai group with an area of 110 millionths, while, the other two above mentioned groups appeared to merge into a Fac group (mean location at 20ºN/193º) with a total area of 350 millionths. These groups were close to the western limb on the 14th and the Fac group was last seen on the 16th. On the 6th, 3 southern hemisphere groups were seen near the eastern limb at similar longitudes: an Hsx group at 12ºS/188º (area 50 millionths), a Dao group at 18ºS/188º (area 120 millionths) and a Bxo group at 28ºS/184º. By the 8th, the Dao group developed into type Dsi with an increased area of 270 millionths. On the 9th, a higher latitude group appeared (at 38ºS/186º). This was not seen on the 11th but the 3 other groups were still visible as they progressed towards the western limb on the 15th and 16th. A single Hsx spot appeared around the eastern limb on the 9th (at 22ºS/126º). As this group progressed across the disk, it became slightly asymmetrical on the 13th when it had an area of 140 millionths. By the 15th, a few accompanying small spots were seen surrounding the Hkx spot. These had disappeared by the 17th when the spot became symmetrical again. It was last seen on the 21st when it was on the western limb. During the period 1st to 16th, more than 10 groups were seen for each of 10 observations made, with a peak of 14 groups on the 9th when R had a value of 208. By the 17th, the number of groups reduced to 7 and then to 5 on the 20th. On the 21st a Fac group and an Hkx spot were seen near the eastern limb. These were at 22ºN/344º and 14ºN/331º respectively. On the 22nd, these had areas of 380 and 290 millionths respectively. By the 24th, the F type group appeared to separate into a leading Hsx spot at 23ºN/352º and an Eac group at 23ºN/332º. The Hkx spot had decayed into a Dac group with an area of 130 millionths. Following these groups were 4 other groups at similar latitudes. Also 2 southern hemisphere groups had appeared around the eastern limb, one of which was a Fac group at 14ºS/290º. This increase in activity meant that a total of 13 groups were seen on the 24th (the last observation of the month).
The largest 2 of the 7 groups seen on the 8th were an Eao group at 19ºN/196º with an area of 220 millionths and an Hax spot at 27ºS/186º with an area of 200 millionths. As the E type group progressed towards the western limb, it comprised symmetrical leading and following spots together with small spots in between. It was last seen on the 12th. A few small spots accompanied the Hax spot on the 9th through to the 12th. Only a small penumbral spot was seen on the 13th when the group was also close to the western limb. The number of groups seen was quite high between the 9th and 12th with either 9 or 10 seen. This decreased to 8 on the 13th and to 6 on the 14th. On this latter date, all the groups seen were small in size, the largest being an Eac group at 18ºN/114º with an area of 130 millionths. On the 17th, the number of groups was still low at 5 but the first of three moderately large groups appeared near the eastern limb. Initially this was a single Hsx spot which became type Dao on the 18th and then type Ehc on the 19th with an area of 370 millionths at 21ºN/336º. It then, on the 19th, comprised of moderately sized symmetrical leading and following spots with a few small penumbral and other spots. When next seen on the 23rd, the group was near the central meridian and was of type Fkc with an increased area of 430 millionths. Now the leading spot was quite asymmetric and irregular while the following spot had also become asymmetric. Several small penumbral spots were seen between the leading and following penumbral spots while a few spots were seen to the east of the following spot. On the 24th, both of the leading and following spots had split into two and indeed by the 25th a further splitting of the leading spot had occurred. By the 26th, further activity around the leading spot meant that its area had increased appreciably such that the total area of the group was 780 millionths. On each of the following 3 days (27th to 29th), the appearance of the leading spot changed significantly. Only the following penumbral spot was seen on the 30th when it was close to the western limb. On the 24th, a small Dso group was seen on the eastern limb. On the 25th, this group was classified as type Fsc with the following spot being the largest of the group. As the group, at 26ºS/245º, moved away from the limb, it could be seen, on the 27th and 28th, that the following spot contained a light bridge towards the groups centre (the group now had the classification of Fkc). On the 29th, the following spot became more asymmetric while the leading spot increased in size. The longitudinal extent of the group was 18º. Several small penumbral spots and other spots were seen slightly to the north of the leading spot. On the 30th, the total group area was at its greatest - 600 millionths. When the group was seen on the 31st, the following spot had become more symmetric while the number of spots within the group had reduced. The third moderately sized group of the month first appeared close the eastern limb as a small Hsx spot on the 27th. It was seen as a Cso group on the 28th. By the 29th, several penumbral spots had developed to make to group, at 25ºN/206º, of type Eac. The leading part of the group comprised of three penumbral spots while following were several smaller penumbral spots. By the 30th, these three spots had joined together to form one large asymmetric leading spot that had several umbra within it. The following part of the group was similar to that seen on the 29th; indeed the area of 360 millionths on the 30th was similar to that of the 29th. By the 31st, the total area almost trebled to 940 millionths and the group was of type Ekc. Both the leading and following spots had increased in size, especially the leading spot which was now quite irregular and had a longitudinal extent of 7º (the group itself was 13º in longitude). Four other penumbral spots were seen on the 31st together with a few other spots.
The rapidly developing northern hemisphere group seen at the end of July (at 25ºN/206º) continued to grow during the first few days of August. On the 1st, it was still of type Ekc with the largest spot being the leading one - this was quite elongated and it contained many umbra. The following spot was also asymmetrical but not to such as extent as the leading spot. When seen on the 2nd, the leading spot had increased in size while the following part of the group consisted of 3 adjacent asymmetrical spots spread out in latitude. The group was now near the central meridian and its area was measured to be 1030 millionths. By the 4th, the longitudinal extent of the group had increased such that the group was classified as type Fkc. The leading spot had split into two and had reduced in size while there was still 3 following spots. The overall structure of the group changed little on the 5th and 6th. By the 7th, the group was nearing the western limb and thus its size appeared to reduce. It was last seen near the limb on the 8th. The other moderately sized group from the end of July, at 26ºS/245º and type Fkc, was of similar appearance on the 1st although the following spot, the largest of the group, had become more asymmetrical. On the 2nd, the leading part of the group had developed many small penumbral spots while the following spot had become even more asymmetrical. On this date, the total area was 680 millionths. When seen on the 4th, the number of spots within the group had reduced as it was close to the western limb. On the 5th, only 4 penumbral spots were seen and on the 6th only the following spot was seen close to the limb. By the 10th, the number of groups on the disk had reduced from between 5 to 9 since the start of the month, to only 3. These were of type Axx at 14ºN/180º, type Cso at 29ºS/130º with area 50 millionths and type Eac at 14ºS/89º with area 180 millionths. The next observation on the 12th (the 11th being extremely cloudy at Truro, Cornwall!) also showed 3 groups: now the groups were of type Hsx at 30ºS/125º with area 60 millionths, type Esc at 15ºS/87º with area 190 millionths and type Cso at 23ºN/359º. The sunspot number for both dates was calculated to be 64 and 51 respectively. On the 14th, the number of groups increased again to 6. One of these was a Hax spot near the eastern limb at 22ºN/335º. When seen on the 15th and 16th the appearance of the group was of 1 main slightly elongated penumbra spot surrounded by a few small spots. By the 18th, a penumbral spot had appeared following close behind the main spot to give a total area of 420 millionths. The group was near the central meridian on the 20th. Subsequent observations showed the group slowly reducing in size such that only a single Hsx spot was seen on the 26th very close to the western limb. On the 20th, 2 groups appeared on the southeast limb. One was a Hkx spot at 18ºS/259º and the other a Dao group slightly further south at 24ºS/256º. As these moved away from the limb, more penumbral spots in the southern most group appeared to make the group of type Fac with a mean location of 25ºS/248º - this being the same location as the Fkc group seen at the start of the month. As the Hkx spot progressed across the disk, it obtained a maximum area of 340 millionths on the 23rd. By the 27th, it had become more symmetrical and then it reduced in size to become type Hsx close to the western limb on the 31st. The number of spots within the Fac group increased in both number and size such that the group became type Fkc on the 27th. On the 28th it had a total area of 690 millionths on the 28th. The latitudinal extent of the group was quite high at almost 10º - the northern limit being at the latitude of the Hkx spot. When seen on the 30th, the number of spots had decreased and on the 31st only a few spots were seen as it was nearing the western limb.
On the 1st, the largest of the 7 groups seen was a Dac group at 21°N/207° that had a total area of 320 millionths. All the other groups on this date were either nearing the western limb or small in size. Up to the 6th, no groups appeared around the eastern limb and those groups that were on the disk were very small in size (types Axx, Bxo or Hsx on the 5th) even though the number of groups on each day remained at 7. On the 6th, an Axx group was seen on the eastern limb. By the 8th, this group had developed into type Dsi that consisted of a compact collection of four small penumbral spots at 14°N/26° . By the 10th, the group had spread out further in both latitude and longitude. On the 111th, one of the penumbral spots had increased in size while the others had decreased. When seen on the 13th, the appearance of the group had changed considerably to become type Dac with a more conventional spread of spots in longitude. The group now had an area of 190 millionths. This group was next seen on the 17th of type Esc and nearing the western limb - it was last seen on the 18th. The largest group seen during the month was first seen on the 8th of type Esi near the eastern limb at 27°S/8° . When seen on the 10th, the leading spot appeared as a slightly distorted symmetrical penumbral spot while the following spot was a quite elongated asymmetrical spot; the total area was estimated at 330 millionths. By the following day, the two main spots had become more symmetrical. The group had a similar appearance on the 13th but when seen on the 17th the number of spots between the leading and following spots had reduced. On the 18th, only the leading penumbral spot remained. On the 17th and 18th a curious group was seen at 13°N/293° . On the 17th the group consisted of several small asymmetrical group and other spots within an area of about 5° by 5° . By the 18th all the penumbral spots had decayed to leave an area of 22 small spots. By the 24th, the group was not on the disk. Observations on the 24th, 25th and 26th showed only 3 groups. The only northern group was a Hsx spot at 21°N/210° with an area of 120 millionths; this was the return of the Dac group seen on the 1st. The other groups were, on the 24th, of type Cso at 20°S/247° with an area of 120 millionths and of type Bxo at 9°S/191° . On the 28th, the Bxo group had decayed and three new groups were seen but all these were small in size.
The observation on the 2nd showed a total of 8 groups, but all were small in size and all were seen consisting of one spot (of type Hsx or Axx). The number of groups and number of spots per group increased over the next 3 days such that on the 5th, 11 groups were seen with R being 157. One of the longest lasting of these groups was initially seen as an Hsx spot near the eastern limb on the 2nd at 22° N/47°. Between the 3rd and 5th it was of type Cso; the group obtained an area of 270 millionths on the 4th. All the accompanying spots surrounding the main penumbral spot had appeared by the 6th and the penumbral spot had become asymmetrical. When next seen on the 10th, it was still of type Hax. The group was last seen on the 14th near the western limb. The most active portion of the Sun seen during the month first appeared near the eastern limb on the 10th. This consisted of an Eac group at 23°N/318° and a collection of small spots some 10° to the south. By the next day, the southern spots appeared to separate into two Bxo groups. In addition, a Dac group had appeared around the limb at 11°N/294°. On the 12th, the E type group had changed to become type Ekc with an area of 460 millionths. The eastern Bxo group had developed into type Dsi (area 80 millionths). Another group, at 22°N/301° and of type Csi appeared on the disk close by to make a collection of 5 groups. By the 13th, the group that had changed to most was the eastern most; this was now type Ekc with an area of 450 millionths. The overall structure of this group was of a main asymmetrical penumbral spot, a smaller following spot with a few smaller penumbral spots between. On the 14th, the northern most group remained of type Ekc but it now had a reduced area of 80 millionths. The Csi group from the 12th was now of type Dai (area 130 millionths). As on the 13th, the most active group was the eastern most as it now had an area of 630 millionths due to the joining together of several penumbra spots into a large following spot that contained several umbra and a light bridge. When this group was seen near the central meridian on the 16th both the leading and following spots had become strongly asymmetrical and much larger in size; the total area was 960 millionths with the following spot still the larger. The group has also become type Fkc. The Dsi group from the 12th had decayed to become type Bxo again. This group and its adjacent Bxo group had decayed on the disk by the 16th. On the 17th, the 3 remaining groups from the active portion of the disk still dominated white light activity. The northern most group was now type Eac with a total area of 250 millionths. The group at 22°N/301° had increased in longitudinal extent to become type Fac but it had an area of only 130 millionths. It was the southern most group that was still the most spectacular. Its area had increased slightly to 1020 millionths due to an increase in the size of the leading spot. Now both the 2 main penumbral spots were of similar size, had irregular shapes and contained many umbra spots of a variety of sizes. On the 18th, the longitudinal extent of this group reduced to become type Ekc but the leading spot had increased in size again although the total area was slightly smaller than on the previous day. When this group was seen on the 19th, it was still of type Ekc but it now had a reduced total area of 780 millionths due to the decaying following spot. The next observation, on the 31st, showed a total of 10 groups spread across the disk and in both hemispheres. The largest group was of type Eac at 25°S/145° with an area of 180 millionths.
The observation on the 6th showed a total of 12 groups. The largest of these was a Dsi group at 19°S/73° with an area of 130 millionths. One of these groups included, on the eastern limb, the return of the large October Fkc group at 11°N/294° which now appeared as two highly foreshortened penumbral spots. Further spots within this group had appeared around the limb on the 7th to make an Ekc group with a mean location of 10°N/291°. By the time of the next observation on the 13th, the now 20° long group straddled the central meridian. It consisted of many moderately sized penumbral spots together with numerous other spots. Even so, the total area was only 350 millionths. When seen on the 16th, this group had decayed into 3 portions. Further decay had occurred by the 18th as only a small Dsi group was seen. Between the 6th and 7th observations, a Bxo group had developed on the disk at 14°N/325° that consisted of 7 small spots. When this group was seen on the 13th it had developed into a Fkc group with a total area of 610 millionths. The largest spot of the group was the leading spot asymmetrical penumbral spot; a collection of smaller penumbral spots followed. The group had passed around the western limb by the observation on the 18th. One of the two southern hemisphere groups seen on the 13th was of type Ekc at 13°S/235° that comprised of a collection of nearby penumbral spots. The largest of these was markedly asymmetrical. The total area of the group was 450 millionths. This group was also seen in October (type Csi when seen on 19th October). By the 16th, all the penumbral spots had merged and substantially increased in size to consist mainly of a single large complex penumbral spot. This contained many umbral spots, the largest being at the leading part of the penumbral spot. At the following part of the group, a spiral penumbral region could be seen. The total area was estimated at 1100 millionths and it was an easy naked eye spot. Two days later, on the 18th, the group now mainly consisted of two penumbral spots; a leading spot had separated from the rest of the spot. Many umbral spots were still present in the now 1400 millionths area group (the largest seen so far this solar cycle). One small penumbral spot was seen just to the north of the leading spot (this spot was also seen on the 16th) while a few other spots were seen near the much larger following penumbral spot. When this group was last seen on the 21st, it had halved in size to 680 millionths due to the following spot reducing in size. Now the leading and following penumbral spots appeared approximately equal in size. The last two observations of the month, on the 27th and 28th, shows a moderate number of groups (9 and 6 respectively) but all were reasonably small in size.
The largest of the 6 groups seen on the 1st were an Eac group at 19° N/100° and a Dac group at 12°S/61° ; the area of these was 220 and 230 millionths. Both groups were still on the disk on the 2nd although the Eac group was approaching the western limb. Over on the eastern limb, a very foreshortened penumbral spot was seen. By the 4th this appeared as a Fhc group at 10°N/309° . On the following day intermediate penumbral spots had decayed to leave penumbral spots at the ends of the group and a small number of spots between. The area of this group was an estimated 580 millionths. When seen on the 9th, the group looked larger as it had just passed the central meridian even though its area had slightly reduced and the following spot appeared to be in the process of splitting into two. The group had a similar appearance when last seen on the 10th. On the 5th, an Axx spot was seen at 8°N/289° and close to the eastern limb. By the 9th, a collection of small penumbral spots and other spots had developed within an area of approximately 5° square. On the 10th, the penumbral spots had all disappeared to leave a collection of 14 spots with no organised distribution. The next observation on the 19th showed only 5 groups but three of these were of moderate size. The first, a Fkc group at 13°S/176°, was seen straddling the central meridian. It comprised a main irregular following spot and a string of small leading penumbral spots. Its area was estimated at 460 millionths. By the next day, the size of the main spot had decreased as well as a reduction in the number of other penumbral spots. By the 23rd the group had become type Ekc where again the largest spot was the following one. The group had passed around the limb by the 26th. The second moderate group from the 19th was a Hho spot at 16°S/126° which had an area of 270 millionths. This group reduced in size slightly as it progressed across the disk; it was near the western limb on the 28th. The third group from the 19th was of type Fhc at 20°N/115° with an area of 910 millionths. It comprised a symmetrical leading spot followed by an irregular penumbral spot and a couple of smaller symmetrical penumbral spots. By the 23rd, the group was some 18° in longitude and it had a pronounced latitude spread of some 8° with the leading spot being closer to the equator. When seen on the 26th this group had decayed slightly and by the 28th, just three penumbral spots were seen. On the 26th and 28th a Fkc spot was seen close to the eastern limb at the high latitude location of 38°N/18° . This group also had a larger following penumbral spot but the total area was only 370 millionths. On the 28th just 4 groups were seen on the Sun.
Last updated on 08 February 2004. |
