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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.
Only 2 observations were made during the month. The first of these, on the 7th, showed two D type groups in the western hemisphere. One of these groups was near the limb. The second observation, on the 14th, revealed a spotless disk.
Solar activity continues to decline - of the 13 observations made during the month only 5 showed sunspots. The most complex group, of type D, was seen on the 1st near the western limb. This group had disappeared around the limb by the 2nd. Three other groups were seen during the latter part of the month. Two were, at best, of type C (on the 21st and 26th) and the third only of type A (on the 29th).
The particularly cloudy weather during the first 3 weeks of the month permitted only 2 observations. The first of the following 6 observations, on the 23rd, showed a D type group near the central meridian. This group was located at 7ºN/206º and the leading penumbral spot had an estimated area of 80 millionths. The group had decayed to a single penumbral spot by the 27th and was last seen on the 29th before passing around the western limb. A nearby C type group was first seen on the 27th but had decayed on the disk by the 29th.
Activity remained very low during April with a measured MDF and R of only 0.38 and 4.38 respectively. All the spots seen during the month were small in size and hence the groups seen were all of types A and B. These groups were also only visible for short periods. The only southern group was seen between the 2nd and 4th at 10ºS/127º. Three other groups were seen later in the month - each on the 17th, 20th and 24th only. The other 10 observations revealed spotless conditions. A bright region of faculae was seen in the northern hemisphere on the 27th under excellent seeing conditions.
Half of the 18 observations made during the month showed a spotless disk. These occurred at the beginning and end of the month. Between the 6th and 15th, 3 groups were seen. The first of these, at 12ºN/337º, was a small A type group and was seen near the central meridian on the 6th and 7th. The most prominent group seen, of D type, was seen at 11ºS/262º between the 7th (when near the eastern limb) and 15th. This was the largest group seen since the third week of March. However, the total area of the group was only 80 millionths (on the 12th). The third group seen, on the 15th only, was a single pore some 15º following the D type group.
Activity has been slightly higher than in May but 8 observations were considered spotless. Sunspots were seen between the 3rd and 12th and between the 21st and the last observation of the month on the 26th. During the earlier period of activity, four groups were seen. The most prominent was of group at 3ºN/292º which first appeared on the disk as an A type on the 4th. The group progressed into a C type with a total of 11 spots on the 7th, while on the 12th it was seen near the western limb as a single penumbral spot. The other three groups were all of type A at 9ºN/346º (3rd and 5th - not seen on the 4th due to poorer seeing conditions), at 10ºS/10º (6th only) and at 9ºS/265º (9th only). During the latter period of activity, a single penumbral spot was first seen at 9ºN/44º on the 21st, while at 13ºN/0º a small A type group was first seen on the 24th. Both groups were still present on the last observation of the month (26th).
The first observation of the month, on the 10th, revealed an Esi group at 8ºS/225º. On the 11th, the total area of this group was estimated to be 400 millionths. The group was last seen on the 13th prior to crossing the western limb. Subsequent observations showed a spotless disk until a small Bxo group was seen on the 26th only and at 9ºN/348º. On the following day, a single penumbral spot appeared near the eastern limb. This was seen as a Dho group on subsequent observations, at 10ºS/262º, and having an area of 420 millionths on the 31st.
The Dho group seen at the end of July continued its passage across the disk in early August. This group obtained a classification of Ehi on the 2nd when it had a total area of 370 millionths and it was located at 10ºS/263º. A small Dsi group at 10ºN/170º was seen on the 10th and 11th. On the 10th only, the first of two high latitude groups were seen at 24ºN/134º, type Axx. The second high latitude group was seen on the 4 days between the 15th and 18th at 29ºN/74º (type Cso). Another Axx group was seen at 11ºN/46º on the 20th and 21st prior to the return of the group seen at the start of the month. This time round, the group was much smaller in size and consisted primarily of one penumbral spot (type Hsx). The mean location of the leading spot was 11ºS/260º. On the 26th, an extensive area of faculae was seen around the penumbral spot and the region following it. An Axx group was seen some 11º following and slightly further towards the south pole (at 14ºS/249º).
The observation on the 1st showed the southern Hsx and Axx groups seen at the end of August (at 10ºS/261º and 12ºS/249º respectively). By the next observation, on the 3rd, the Hsx spot had decayed into a single spot (type Axx) and it was the only spot seen on the disk. The remaining 11 observations made during the month revealed no sunspots. The active area MDF for the month was very low at 0.23, as was R at 2.62.
Of the 10 observations made during the month, only 1 showed any spots. This was on the 26th when two groups, each consisting of only one pore, were seen at 28ºN/216º and 2ºN/170º. Thus, the active area MDF for the month was again very low at 0.20, as was R at 2.20.
The first 5 observations of the month followed on from October with no spots being seen. Between the 13th and 16th, a small Hsx spot was seen at 2S/290. Two other small groups were seen at 28ºN/288º and 16ºS/252º before another Hsx spot was seen on the 18th at 7ºN/248º. This latter spot appeared only as an Axx pore on the 21st together with a Bxo group at 8ºS/169º. The observation on the 23rd showed a marked increase in activity with two moderately size D type groups. These were at the location of the 2 small groups seen just two days earlier. By the next observation on the 28th, the westward of the D type groups had passed around the limb, while the other had increased in size to 540 millionths. It had also become an Ehc group and how had a mean location of 3ºS/171º. This group was still visible on the last day of the month. The previous group with such a large area that I observed was almost 3 years ago in January 1994. Several prominent polar faculae were seen under good seeing conditions in the month on the 8th. The active area MDF and R values were almost the same as that of August 1996.
The E type group seen towards the end of November was still visible on the 2nd but only as an Hsx spot near the western limb (at 2ºS/171º). The next two observations, on the 4th and 5th, showed a spotless disk. The next observation on the 14th revealed an Eao group near the western limb at 26ºS/356º. An area of faculae was seen between the spots of this group. Also on this date, the D type group last seen on the 23rd November was seen again - this time as a Cso group at 8ºN/254º. This group was near the western limb on the 22nd and 23rd and appeared as a single penumbral spot. On the 22nd a Bxo group was seen at 8ºN/240º. On the 24th, only a single pore was visible (at 17ºS/170º). The four remaining observations of the month showed spotless disks.
Last updated on 25 April 2002. |
