|
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 Hax spot seen on 31st December containing a light bridge had almost separated into two penumbral spots on the 1st. By the 3rd, several penumbral spots were seen to form a Dso group. The group was now near the western limb (at 21°N/306°). The Eso group also seen on 31st December had decayed into type Cao by the 1st as it also approached the western limb (at 22°S/349°). The third group seen on the 31st December was similar in appearance on the 1st as a Dsi group near the central meridian (at 28°S/279°). The number of spots in this group had reduced by the 3rd. The next three observations on the 5th, 7th and 9th showed blank disks. On the 10th only a single Axx spot was seen at 25°S/132°. The next observation on the 14th showed a small Dai group just past the central meridian at 22°S/121°. The total area of the group was only 140 millionths. Also on this date, a small single Hsx spot was seen at 15°S/45° which had decayed into type Bxo by the 20th and was not seen on the 21st. Another Bxo spot was seen in the 20th and 21st at 27°N/346°. The last observation of the month, on the 26th, showed a marked increase in activity with 5 groups being seen. The three northern groups were all small (types Axx at 12°N/279°, Cro at 15°N/267° and Bxo at 28°N/266°). The two southern groups were of types Dso at 21°S/350° with an area of 170 millionths and Fso at 36°S/279° with an area of 270 millionths. Both the monthly averaged R and AA values have reduced compared to November and December 1997 but are similar to October 1997.
The high latitude Fso group seen at the end of January had decayed into a single Hsx spot by the 2nd (at 37°S/285° and near the western limb). This was the only group visible on this date. The next observation on the 7th showed a small Cso group approaching the western limb at 19°S/215°. It was seen on the 8th but it had passed around the limb by the following day. The other group seen on the 7th was a single Hsx spot at 22°S/119° which had an area of 50 millionths. This spot was the remains of the Dai group last seen on the 14th January. The Hsx spot remained until the 13th when it became type Hrx and then an Axx spot on the 14th and 15th before passing around the western limb. Also on the 8th a high latitude Bxo group was seen at 38°S/90°. It changed little for the next two days before becoming type Axx on the 11th. It decayed on the disk by the 13th. On the 9th and 10th only, a short lived Axx group was seen at 22°S/89° while on the 10th only a Bxo group was seen near the centre of the disk at 13°S/100°. The 11th saw the arrival, near the eastern limb, of what was to become the largest group of the month. When first seen it was of type Dso at 24°S/36°. By the 13th it had developed into type Eai with an area of 380 millionths. The group comprised a leading asymmetrical penumbral spot followed by several penumbral spots and other spots. The following penumbral spots had increased in size by the 15th and 17th before the size and number of following spots decreased by the 18th. Throughout this period, the leading spots changed little while the group as a whole had a maximum area of 420 millionths. By the 22nd, only the leading penumbral spot was seen very close to the western limb. On the 13th, the first two northern groups of the month were seen. Both were of type Axx at 26°N/22° and 32°N/8°. The first of these was only seen again on the 14th while the second developed into type Bxo on the 14th and 15th before decaying on the disk. The other new group seen on the 13th was a small Cso group at 20°S/14°. This group was still of this type on the 15th before decaying into type Bxo by the 22nd as it neared the western limb. Also on the 14th and 15th a Axx spot was seen at 23°N/2 which became type Dro by the 17th before decaying into type Bxo on the 18th. On the 22nd one additional group was seen at 21°S/333° and type Axx. By the 24th it had become type Dso with an area of 70 millionths. The number of groups increased to 5 on the 24th with the arrival of a Dso group, area 90 millionths, near the central meridian (at 16°N/278°). Three other small groups were seen on the 24th at 21°N/303° (type Axx), 28°N/239° (type Bxo) and 25°S/261° (type Bxo). By the 28th, the Dso group at 16°N/278° was unchanged in appearance while the southern Bxo group had changed into type Cso (area 50 millionths). These were joined by groups at 20°S/285° (type Cso) and at 23°S/236° (type Dso). The other Dso group seen on the 24th (at 21°S/333°) would have passed around the limb by the 28th. Although 18 groups were seen during the month, only one had an area greater than 100 millionths. The majority of the activity was in the southern hemisphere (12 southern and 6 northern groups), especially during the first half of the month. Both R and AA mdf's were approximately twice that of January and were at similar levels to last December.
Of the four groups seen on 28th February, only one had changed substantially by the 1st. This was the Dso group at 23°S/235°. A following penumbral spot had developed and there were additional small leading penumbral spots. This group enlarged again by the 2nd to become type Esi with an area of 200 millionths. When next seen on the 5th, it was of type Fko and close to the western limb. The group was now dominated by approximately equally sized leading and following penumbral spots. The group was not seen on the 7th as it had passed around the limb. The three other groups seen on 28th February were all small in size. These were at 21°S/286° (type Cso), 15°N/283° (type Dso) and at 26°S/255° (type Axx) and all were seen again on the 2nd before they all passed around the western limb by the time of the next observation on the 5th. Also on the 1st, a small Bxo group appeared on the disk at 22°N/208° - it developed into a small Dso group by the 5th before decayed into a Cso group by the 7th and passing around the limb. The 7th saw the arrival of 2 high latitude spots at almost the same longitude close to the eastern limb. These were at 46°N/65° and 41°S/63°. The northern of these was of type Hsx which had not changed type when seen on the 9th but it had decayed into an Axx spot when seen on the 14th. It was not seen on the 18th. The southern group developed from type Axx on the 7th to Bxo on the 9th and into a small Eao group by the 14th. It subsequently decayed on the disk as it was not seen on the 18th. The longitude of these two groups changed from observation to observation due to the differential rotation of the Sun. The synodic rotation period of these two groups was calculated as 30.9 days for the northern spot and 29.4 days for the southern group. The 7th also saw the arrival on the disk of a small Dso group at 18°S/97° which decayed into type Cso by the 9th and then into type Axx by the 14th. Also on the 14th three other groups were seen in the same region just to the east of the central meridian and in the southern hemisphere. One of these groups was an almost random collection of 30 small penumbral spots and other spots at 20°S/32°. The second group was an Hsx spot at 16°S/23° which had an area of 120 millionths. The third group was an Axx spot at 30°S/23° which was only seen on the 14th. By the 18th the collection of spots had developed into a bipolar group with the leading and following penumbral spots dominating. The Hsx spot seen on the 14th was now sufficiently close to the bipolar group to be part of the same active area. This together with a single spot leading the bipolar group lead to an overall classification of Fkc with an area of 670 millionths. By the following day (19th), the corrected area of the group had increased to 860 millionths. The 18th saw two Axx groups at 41°S/52° (perhaps part of the southern high latitude group seen earlier in the month) and at 22°N/293°. The southern group was not seen on the 19th. The northern group developed into type Cso by the 19th and was still on the disk by the time of the next observations on the 27th and 28th. It was then of type Dso and close to the western limb. The only other group seen on the 27th was an impressive Fhi group at 24°S/235° which had one large following penumbral spot together with a string of leading small penumbral spots and other spots. The longitudinal extent of the group was 27° which spanned the central meridian. The area of the group was 500 millionths. This group was the return of the Fko group last seen on the 5th. By the following day, the 29th, there was more than 10° between the following penumbral spot and the other spots so that they were classified as two active areas (one of type Hhx at 24°S/221° and the other type Fsi at 24°S/241°). Two other small groups were seen on the 29th - a Bxo group at 31°N/199° and an Hsx spot very close to the eastern limb at 21°S/138°.
The F type group with the unusual dominant following penumbral spot from the end of March at 24°S/241° had changed into two equally sized penumbral spots when it was seen near the western limb on the 2nd (at 25°S/235° and 23°S/222°). The group was not seen on the 5th. On the 2nd another F type group was seen nearing the central meridian at 21°S/138°. This group had the classification Fsi but its penumbral spots were all small in size and hence the group had a total area of only 80 millionths. When next seen on the 5th, the following penumbral spot had decayed to make the group of type Cso. In addition, many of the other spots had decayed. On the 6th only a Hsx spot and an Axx spot were seen at either ends of the earlier group. Only the Hsx spot remained on the 7th. On the 5th a compact Dso group was seen at 22°S/85° with an area of 180 millionths. This group developed into type Eao by the 7th with an area of 270 millionths before decaying into type Cso and then Hsx types as it approached the western limb. The Fkc group last seen on 19th March reappeared near the eastern limb on the 5th as type Dso at 17°S/38°. By the 7th this group changed into type Eso which had an area of 390 millionths. By the 16th, it had decayed into type Hsx and it was then near the western limb. When this group was near the eastern limb (on the 6th and 7th) a Hsx spot was seen just to the south (at 27°S/36°). On the 7th a small Hsx spot was seen very close to the eastern limb. By the 12th this region had decayed into two Bxo groups at 27°S/8° and 24°S/2° which together covered an area of 10° in both latitude and longitude. The number of spots within these groups peaked at 16 on the 14th. The northern of these groups was still seen on the 16th but the southern group was last seen on the 14th. The 12th saw a Cso group at 25°S/52° with an area of 60 millionths. This was still visible on the 16th but only as an Axx spot. The first significant northern group of the month was seen on the 16th at 28°N/4°. This was a Dso group with an area of 110 millionths. It was not seen on the 19th when another northern Dso group was seen at 21°N/313°. This group was of type Eso on the 20th and 22nd. It then decayed into type Cso by the 23rd as it approached the western limb. At its peak, this group had an area of only 120 millionths. The 27th saw a Hsx group at 16°S/138° which had an area of 200 millionths. The penumbral spot was accompanied by several close by spots when seen on the 28th and 29th. During the month 10 other smaller group of types Axx and Bxo were seen. As with the other groups seen during the month, the majority of these were in the southern hemisphere.
The Hax spot seen on 29th April at 16°S/135° had increased in size to 420 millionths by May 2nd when it was near the central meridian. Several umbral spots were seen within the penumbral region of the now Hkx spot. There were also several spots surrounding the penumbral spot. As this group progressed towards the western limb, the shape of the penumbral spot changed slightly each day while the number of accompanying spots reduced in number. On the 2nd, a small Eai group was seen at 27°N/97° approaching the central meridian. The number of spots within the group increased rapidly (to 39 on the 5th) and the size of the leading spot also increased. By the 8th, the group had become type Fki with a corrected area of 660 millionths. This group was seen were close to the western limb as an Hsx spot on the 10th. Also on the 2nd an Hsx spot was on the eastern limb. This was the remnant of the Eso group last seen in the middle of April. The appearance of the single spot (at 16°S/41°) did not change as it progressed across the disk and was last seen on the 14th. The next group to appear was a Dsi group at 19°S/349° on the 8th. This had developed into type Eai by the following day but its maximum area was only 270 millionths (on the 10th when it was of type Esi). More penumbral spots appeared within the group as it approached the western limb on the 19th. Yet another small Esi group appeared around the eastern limb on the 11th (maximum area 100 millionths). By the 16th it had decayed into a Csi group at 26°S/285° and then into type Bxo on the 18th. The number of spots continued to reduce such that only one Axx spot was seen on the 21st when it was seen within a band of faculae. Also on the 11th an Axx spot was seen near the eastern limb surrounded by an area of faculae. For the next three days it was of type Cai at 22°N/285° with the penumbral spot following. It then developed into type Eai when a small leading penumbral spot appeared. By the 16th, the longitudinal extent of the group increased to become type Fai but with an area of only 160 millionths. The number of spots reduced after the 19th and the group become Dso and it was last seen on the 22nd. By the 24th, a Dsi group had developed on the disk at 18°N/209°. It had an area of 280 millionths on the 25th. It was at the western limb on the 28th. The 25th saw the return of the group last seen on the 10th. This was in the form of an Hax spot. When seen on the 28th, 29th and 30th this group consisted of just two fairly small adjacent penumbral spots at 26°N/98°. On the 30th two Bxo groups were also seen at 21°S/132° and 18°S/45°. During the month 8 Axx groups were also seen - these were on the 8th at 28°N/358, on the 11that 8°S/41°, on the 19th and 20th at 16°S/304°, on the 19th at 31°S/251°, on the 22nd at 23°N/265° and on the 24th and 25th at 18°S/135°, on the 28th and 29th at 18°S/106° and on the 30th at 21°S/73°.
The first observation of the month, on the 7th, showed a Chi group approaching the central meridian at 20°S/351°. This group comprised a moderately size penumbral spot (area 370 millionths) with 12 small following spots. By the next day, the number of following spots had reduced to 10 and only to 5 by the 10th when the group became type Hhx. The penumbral spot then reduced in size slightly as it neared the western limb and it was last seen on the 14th. Also on the 7th a small Csi group was seen at 21°N/23° (area 50 millionths) and a small Dai group at 20°S/41° (area 90 millionths). The number of spots in the Csi group reduced slightly by the 8th and only a single Axx spot was seen on the 10th. The Dai group had decayed into type Cso by the 8th. It was not seen on the 10th as it would have been near the limb. On the 10th, two small Cso groups were seen at 22°S/15° and 25°S/316°. On the 12th, the western of these groups had grown into type Eso but was very close to the western limb. Meanwhile, the other group had decayed into a Bxo group on the 12th and it had decayed on the disk by the 14th. A Hsx spot was seen near the eastern limb on the 12th at 20°S/238°. This spot was of type Hax with an area of 90 millionths on the 14th. By the 14th it had decayed into a Bxo group and then into an Axx spot on the 17th and 19th. This spot was not seen on the 20th but a single spot was seen again on the 21st. Only an area of faculae remained on the 22nd. The Dsi group last seen on 28th May returned on the 14th as an Hsx spot with an area of 160 millionths accompanied by a few small spots. Observations on the 16th, 17th and 19th also shows a few accompanying spots but, on the 20th, the number of spots increased to 10 and the classification of the group changed to Cai (area now 190 millionths and at 17°N/212°). On the 21st some of the accompanying spots developed penumbra and the group became type Dso with an area of 300 millionths. The group had a similar appearance on the 22nd. By the 24th, only the leading penumbral spot and two small spots were seen as the group neared the western limb. A high latitude Bxo group at 34°N/349° developed on the disk near the central meridian between the 14th and 16th. The group gradually decayed and it was last seen on the 20th. Also on the 16th a single Hsx spot was seen near the eastern limb at 27°S/178°. Observations on the 17th, 19th, 20th and 21st showed no change in the appearance of this spot and it had an area of 60 millionths. On the 22nd two small spots were seen near the penumbral spot. These were absent on the 24th. On the 19th an Axx group appeared on the disk at 16°N/225°. By the 21st a leading penumbral spot has developed and by the 22nd the group was of type Dso but it has an area of only 50 millionths. It was not seen on the 24th when it would have been close to the limb. On the 24th an irregular Hax spot appeared near the eastern limb. The main penumbral spot was quite elongated in the longitude direction and it included several umbra. During the month an additional 12 Axx or Bxo groups were also seen. The Axx groups were seen on the 7th at 16°N/340°, on the 8th at 30°N/348°, on the 8th and 10th at 18°S/341°, on the 14th at 21°S/250° and on the 24th at 22°S/70°. The Bxo groups were seen on the 7th and 8th at 23°S/290°, on the 12th at 24°S/290°, 24°N/279° and 33°N/254°, on the 14th at 28°S/262°, on the 17th at 24S/225° and on the 20th and 21st at 29°S/190°.
The first observation after returning from holiday, on the 13th, showed a small Dai group at 20°S/215° (area 110 millionths), a Cro group at 17°N/215° (area 30 millionths and only seen on the 17th) and two Axx spots. The Dai group reduced in size as it progressed across the disk to become type Bxo on the 18th. Unusually, on the following 2 days the group's size increased to become type Cao before the main penumbral spot lost its surrounding spots to become type Hsx on the 21st and as it neared the western limb. The next significant group appeared on the disk, just to the east of the central meridian, as an Axx group on the 15th at 20°S/196°. By the next day it had developed into a small Dao group with a leading penumbral spot, two following penumbral spot and 4 intermediate spots. The appearance of this group changed into type Cso on the 21st and then into type Hsx as it progressed towards the eastern limb. Its maximum area was 120 millionths on the 19th. On the 20th, a Bxo group developed on the disk just to the west of the central meridian at 13°S/178°. By the following day it had developed into a Dso group with an area of 110 millionths. This group subsequently decayed into type Cso as it neared the western limb. On the 21st, two Cso groups were seen at almost the same longitude and at the same latitude north and south of the solar equator at 26°N/104° and 26°S/99°. The northern group changed little and was still of the same type on the 26th before it decayed into type Axx on the 27th. The southern group developed into type Dso by the 22nd but with an area of only 30 millionths. It then decayed into type Bxo on the 23rd and 24th before becoming type Axx on the 25th. Another Cso group, seen on the 22nd at 16°N/64°, was first seen as an Axx group on the previous day near the eastern limb. It was still type Cso on the 25th with an area of 40 millionths. It decayed into type Axx on the 26th and was not seen on the 27th. The largest group seen during the month first appeared as a Hsx spot near the eastern limb on the 21st (at 22°S/59°). By the next day following penumbral spots were seen which made the group of type Eho. On the 23rd, the corrected area of the group was 610 millionths. The dominant spot of the group was the leading penumbral spot. The number and size of the following spots reduced as the group progressed across the disk. By the 29th, there was only one small following penumbral spot. The leading spot changed little during this period. On the 22nd, a single Axx spot was seen at 31°N/54° close to the eastern limb and surrounded by an area of faculae. By the 23rd this group became type Cso and then into type Dai on the 24th. On this date, the group consisted of a collection of closely packed penumbral and other spots. By the following day, the 25th, three irregularly shaped penumbral regions were seen close together. By the 26th, these penumbral spots had combined together to give one irregular spot containing several umbra. The group continued to increase in size such that on the 27th the total area was 500 millionths and of type Dko. By the 29th the group area was 350 millionths. On the 27th, a Bxo spot had formed on the disk at 29°N/82° which by the 29th had developed into type Cao with an area of 50 millionths. Also on the 27th a small Hsx spot was seen at 25°N/350° and near the eastern limb. This group was of similar appearance on the 29th. From the 13th, 12 additional Axx or Bxo groups were seen.
Activity during August was the highest so far this solar cycle with R just above 100. Not only did the number of groups increase but also the size and complexity of some of these groups. Six groups dominated activity during the month. The first of these appeared on the 2nd as a small Cso group near the eastern limb. Two days later a following penumbral spot had appeared around the limb to form a Fao group. More spots between the leading and following penumbra had appeared by the 5th; some of these were penumbral spots. One of these intermediate spots became the largest spot of the group on the 7th when the group had a classification of Fkc, it was at 22ºS/265º and had a total area of 500 millionths. On the 8th, when the group was near the central meridian, this intermediate spot had decayed slightly. By the 10th, the following penumbral spots had decayed leaving what was the intermediate penumbral spot as the new following spot. Also the number of spots within the group had increased. As the group moved nearer to the western limb, the appearance of the group changed little. It was last seen on the 13th. The next significant group was first seen on the 6th as an Hhx spot on the eastern limb. On the 7th it was clear that this spot was asymmetrical in shape; it was also joined by a small following penumbral spot. By the 9th the following spot had decayed to leave a Hkx spot at 31ºN/209º with an area of 550 millionths. Several umbra were seen. By the 10th the spot had decayed into two spots with the following spot being close by and smaller than the leading spot. On the 12th and 13th additional accompanying spots were seen. On the 15th, the following penumbral spot had disappeared while on the 16th other small penumbral spots had formed. Between the 17th to 19th fewer accompanying spots were seen as the group neared the western limb. On the 7th, a northern hemisphere Hsx spot was on the eastern limb. This group also had a dominant leading penumbral spot together with close by small spots. On the 10th, the group had its maximum area of 580 millionths when it had a classification of Dko and was at 16ºN/165º. The shape of the leading penumbral spot changed from day to day such that on the 12th it was quite elongated and had two large and almost equally sized umbra. On the 13th, it became clear that the group was going to split into two. This did indeed happen; on the 15th two penumbral spots were seen and each included one of the large umbra seen on the 12th. The two penumbral spots remained close together as the group progressed across the disk. The group was last seen in the 20th. Another Hkx spot was seen on the 19th when it was near the eastern limb. By the 21st, the large asymmetrical spot included several umbra and a region of photosphere. It also had two small leading penumbral spots. On this date, the group had a corrected area of 630 millionths, had a classification of Dko and was at 31ºN/36º. The appearance of the group changed little when seen on the 22nd but by the 24th the main penumbral spot had split into two. Further decay had occurred by the 27th when the group was only of type Dao. The now much reduced group was still on the disk on the 31st but was very near to the western limb. The group that was to become the largest of the month was first seen on the disk as a single Axx spot on the 24th. By the 27th, a total of 31 spots had developed; the group was also near the central meridian. On the next day, some of the leading and following spot developed penumbra. The size of the leading penumbral spots had increased by the 29th. When seen on the 31st, an impressive single large leading penumbral spot was present; the group was now of type Fkc, at 20ºN/1º and had a corrected area of 910 millionths. It had also merged with the penumbral spots of a following group to give a longitudinal extent of almost 25º. The final dominant group of the month was the return of the southern group seen earlier in the month. Now at 23ºS/276º it was seen as a Dho group near the eastern limb on the 29th. When seen on the 31st it was of type Ekc and had a corrected area of 840 millionths. Its appearance was of three close irregularly shaped penumbral spots. During the month another 32 groups were seen, with a maximum of 9 seen on the 19th. Almost twice as many groups were seen in the northern hemisphere as in the southern hemisphere.
The northern of the two dominant groups seen at the end of August was near the western limb on the 3rd. The other dominant group was now near the central meridian and had an area of 1340 millionths (probably the largest area group of this solar cycle so far). This group consisted of two close by asymmetrical penumbral spots with a few surrounding spots. Both of these penumbral spots were seen to the naked eye. The mean location of this group was 20ºS/272º and it was of classification Ekc. The appearance of the group was similar on the 4th but both main penumbral spots had decayed in size when seen on the 7th. The group was last seen near the western limb on the 8th. On the 7th, three northern hemisphere groups were at almost the same longitude. These were at 15ºN/198º (type Dso, area 170 millionths), 22ºN/198º (type Dao, area 110 millionths) and 31ºN/197º (type Hsx, area 40 millionths). Of these three groups, the southern most group lasted the longest - it was the only one visible on the 12th. A similar arrangement of three groups was seen again later in the month but in the southern hemisphere. On the 20th, for example, three groups were at 15ºS/50º (type Cso, area 40 millionths), 28ºS/53º (type Dai, area 60 millionths) and 38ºS/62º (type Dao, area 50 millionths). Only the middle of the three was seen on the 25th, although a small Dso group appeared at 11ºS/42º on the 27th. Although solar minimum was over two years ago, several high latitude groups were seen during the month: at 31ºN/196º between the 3rd and 8th (type Hsx), at 38ºS/63º between the 16th and 23rd (type Dao on the 20th), at 31ºN/19º between the 17th and 27th (type Hsx) and at 38ºN/358º between the 20th and 25th (type Cso on the 21st). The second largest group of the month appeared around the eastern limb on the 17th. When seen on the 21st, it was at 19ºN/13º, of type Dki and had an area of 400 millionths. Its appearance on this date was of a main irregularly shaped penumbral spot surrounded by small penumbral spots and other spots. The size of the group on the 23rd was 480 millionths and the main penumbral spot was still quite irregular in shape. The number of surrounding spots increased as the group passed the central meridian. When last seen on the 27th, only three attendant spots could be seen together with a more symmetrical main penumbral spot. On its passage across the disk, this group had a small preceding Cso group at 18ºN/27º. Although there were fewer prominent groups compared to August, the group MDF and sunspot number were both slightly higher.
Another D type group was seen on the 15th at 17ºS/107º. This had an area of 250 millionths equally split between the two main penumbral spots. By the 18th, this group was of type Eao with an area of 360 millionths (to become the largest group seen during the month). The group was last seen on the 19th when it was near the western limb. On the 18th a total of 9 groups were seen - these comprised the above E type group, 3 small D type groups, 2 A type groups and one C, B and H type groups. Six of these were in the northern hemisphere. The number of groups seen reduced to 4 on the 25th and down further to 2 on the 28th. On the 29th, the number of groups increased again to 6 including the return of the leading spot of the Cao group seen on the 11th. Now this group consisted of a single Hhx spot at 19ºN/187º. When this group was seen on the 30th, the main penumbral spot was accompanied by 2 small spots that changed the group into type Cho. On this date, all the other groups seen were all small in size. Not only was the solar activity, in terms of group MDF and sunspot number, smaller than in September, the size of the groups seen were significantly smaller than in recent months.
On the 1st, the largest of the four groups seen was of type Dko at 18ºN/183 with an area of 220 millionths. The two penumbral spots of this group were very close together; only three other spots were seen within this group. All these groups had passed around the limb by the time of the next observation on the 11th. Of the seven groups seen on this date, four had penumbral spots: a Hax group at 24ºN/128º (area 70 millionths), a Cso group at 15ºN/115º (130 millionths), a Dao group at 13ºS/49º (area 80 millionths) and a Hkx group at 27ºS/32º (480 millionths). This latter group was the largest seen during the month. The Hkx group, when seen on the 14th, was of type Dko and comprised of an asymmetrical leading spot which was closely followed by two small penumbral spots. The appearance of this group changed little as it progressed across the disk and it was last seen on the 21st close to the western limb. The number of groups reduced as the month progressed to four on the 17th, three on the 20th and just two on the 21st. Other than the group Dko group mentioned above, all the other groups seen on these dates were small in size. On the next and last observation of the month, on the 29th, the number of groups had increased to five. The westerly of these was of type Dso at 25ºN/288º which must have developed on the disk since the 21st. Close to the central meridian was a Cao group at 18ºS/210º. This group had a leading penumbral spot of area 180 millionths with a large number of following spots. The longitudinal extent of this group was 15º. Another long group, of 30º extent, was seen at 19ºN/189º which comprised variously shaped penumbral spots amongst other spots. The group was classified type Fai and it had a total area of 310 millionths. Also on this date a Bxo group was seen at 29º/171º and a Dso group was seen close to the eastern limb at 14º/139º. Although not many observations were possible during November, it appears that activity was similar to October.
The long Fai group seen at 19°N/189° at the end of November had decayed into 2 groups by the 6th. These groups were of types Hsx at 21°N/190° and Cao at 21°N/172° and both were seen approaching the western limb. Also seen on the 6th was a single Hkx spot at 16°N/139° and near the central meridian with an area of 280 millionths (it was seen as a Hsx spot on the 12th). A similarly sized Dao group was also seen near the central meridian at 17°N/119°. The other 4 groups seen on the 6th were all small in size. By the 12th, southern hemisphere activity was the more dominant with a Fsi group at 27°S/24°, area 220 millionths, and a nearby Csi group at 18°S/36°. Both of these groups were just east of the central meridian. By the 19th, the F type group was very close to the western limb and it was of type Dso when last seen on the 20th. The C type group was not seen on the 19th. On the 19th, an Eso group was seen at 21°N/254° with an area of 180 millionths - the several penumbral spots of this group were all small in size. This group had a similar appearance on the 20th but had decayed into an Axx spot by the 24th. Also on the 24th, a small Esi group was at 24°N/224° that consisted of a spread out collection of small penumbral spots - the latitude and longitudinal spread being about 10° in both directions. By the 28th, this group had developed into a complex Ehc type group with a main leading penumbral spot and a variety of asymmetrical following penumbral spots. The total area of the group was 600 millionths. Seen close to the eastern limb on the 24th was a Dso group at 30°N/172°. This group also developed into a complex group by the 28th when it was of type Eac. The leading spot was smaller than the other E type group but it had large number of small following penumbral spots. The total area of this group was 370 millionths. A small southern Dai group at 21°S/159°, with an area of 100 millionths, was also seen on the 28th. This group brought the total sunspot area on this date to just over 1000 millionths - the largest daily area total seen since early September.
Last updated on 25 April 2002. |
