Introduction
Sunspot Activity Notes
Disk Animations
Disk Drawings
Eclipses of the Sun
Glossary
Hydrogen Alpha
Sunspot Measurements
Observing the Sun
Parallactic Angle
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Stonyhurst Disks
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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.

January 2007

The first observation of the month, on the 4th, showed three groups which were all in the eastern part of the disk. AR 933 at 3°S/32° was of type Cao with an area of 180 millionths. Just to the north of this group was an Axx spot at 4° N/35° (AR 934). Further towards the eastern limb was a single Hsx spot at 6°S/9°, AR 935, which had an area of 230 millionths. When next seen on the 10th AR 933 was nearing the western limb and was now of type Dso. AR 935 was still of type Hsx and it had a similar area as on the 4th. These two groups were joined by an Hsx spot, AR 937, at 13°S/348°. By the 14th AR 933 and 935 had rotated off the disk while AR 937 must have decayed on the disk. However, on this date an Axx group, AR 938, was seen near the eastern limb at 4°N/226° . This group was seen again on observations made the 15th and 19th but it had decayed by the 21st.

On the 21st a small Dsc group with an area of 90 millionths had formed on the disk at 4°S/212° . It was of similar appearance on the 23rd but was only seen as a single Axx spot close to the limb on the 25th. The next observation on the 27th showed an Hsx spot close to the eastern limb at 3°S/42° (AR 940). By the 31st additional spots had formed at the leading part of the group to make the group type Dai with an area of 120 millionths. Also on the 31st another single Hsx spot was seen further towards the eastern limb at 7°S/9° (AR 941).

Hydrogen Alpha:

From just 4 observations the most striking prominences of the month were a thin curved jet prominence that appeared from a segment of higher than usual limb on the 25th and a arched shaped prominence was seen on the SE limb at approximately 70°S on the 31st. Near one of the bases of this arch prominence a filament could be seen close to the limb. A more striking filament was also seen on the 31st to the east and north of AR 940 which was quite curved near the group before stretched out towards the north.

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February 2007

On the 2nd two groups were seen. AR 940 at 4°S/42° had an area of 230 millionths, was of type Dsc and consisted of a larger follower penumbral spot and two small leading penumbral spots surrounded by several other spots. AR 941 at 6°S/7° was a single Hsx spot of area 180 millionths. On the 3rd and 4th the number of spots in AR 940 reduced such that there were only 3 spots on the 4th. Meanwhile AR 941 remained as a single Hsx spot on these two dates.

The next observation on the 11th showed a blank disk. On the 15th only an Axx group was seen at 7°S/227° which consisted of 3 spots. On the 17th a small Hsx spot was seen at 11°S/133° (AR 942) which became a Bxo group on the 21st; the group had decayed on the disk by the 25th. Another single Hsx spot, AR 944 was seen on the 25th at 7°S/45° with an area of 70 millionths. It was seen near the central meridian on the 28th.

Hydrogen Alpha:

On the 3rd and 4th filaments were seen to the south and east of AR 940 and to the south of AR 941. Only small prominences were seen on these two days. On the 11th more prominences were seen but all were fairly small. On the 17th a more substantial prominence was seen on the south east limb. However the largest prominence seen from the 5 observation made during the month was on the 28th when two spike prominences were seen close to each other on the SW limb.

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March 2007

For 25 observations just 5 small groups were seen.  On the 1st a Hsx spot at -5°S/46° (AR 944) had just passed the central meridian which had an area of 70 millionths.  It was of a similar appearance on the 2nd, 3rd and 5th when it was close to the western limb (it was not seen on the 6th having passed around the limb).  On the 5th AR 945 was seen on the disk at 5°S/6° as type Bxo. Just a single spot was seen on the 6th and it had decayed by the 7th.  After 4 blank observations, another Bxo group developed on the disk on the 11th at 7°N/315° (AR 946). This also decayed into an Axx spot by the following day when it was close to the western limb. Observations from the 13th to 21st inclusive and on the 25th showed no sunspots.  Yet another Bxo group, AR 948, developed on the disk on the 26th at 1°S/101° which also decayed into an Axx spot by the following day before disappearing by the 28th.  The final group seen during the month was an Axx spot at 9°N/332° near the eastern limb on the 28th (AR 949).  The next and final observation of the month was also devoid of sunspots.

Hydrogen Alpha:

The most notable prominences seen from 10 observations was on the 10th and 11th: on the 10th two sets of closely spaced prominences were seen on the SE limb.  By the 11th activity had reduced to give one remaining prominence from each set and the northern most resembled a chimney with smoke appearing from the top and then at right angles to the chimney. No notable filaments were seen during the month.

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April 2007

Observations on the 2nd, between the 4th and 12th inclusive and between the 14th and 22nd inclusive showed blank disks. The next observation the 28th revealed a moderately size Dko group at 9°S/308° with an area of 270 millionths (AR 953).  It comprised of one main penumbral sunspot with a small number of surrounding spots including a small following penumbral spot.  By the following day the surrounding spots had disappeared to leave a Hkx spot with an area of 380 millionths. This spot has increased in size again by the 30th to 410 millionths when it was seen with the protected naked eye. On the 29th a Bxo group, AR 954, had developed on the disk at 4°S/289°. On the 30th it was of type Cso with an area of just 30 millionths.

Hydrogen Alpha:

Although prominences were seen throughout the months, none were particularly striking. Activity on the disk only increased when sunspot groups AR 953 and 953 were present at the end of the month when several filaments and plages associated with these groups were seen.  Prior to that the disk was devoid of filaments.

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May 2007

AR 953 at 9°S/307° was still visible with the protected naked eye on the 1st and 2nd when it was close to the central meridian. It attained its largest area on the 2nd at 340 millionths when it was of type Dkc due to the presence of a small penumbral spot seen following the main asymmetric leader penumbral spot.  By the 4th the group was of type Hax with a reduced area of 210 millionths.  It was of a similar appearance on the 5th as it neared the western limb.  On the 1st and 2nd AR 953 was accompanied by AR 954 at 4°S/288° as a small Hsx spot on the 1st and a Bxo group on the 2nd.  It was not seen on the 4th having decayed on the disk.

The next observation on the 10th showed a small Dai group, AR 955 at 9°S/179°, approaching the central meridian.  It has an area of just 60 millionths. The number of spots within the group had increased by the 12th.  It had decayed by the next observation on the 15th.

AR 956 was first seen at 3°N/72° as a Dac type group on the 15th when it had an area of 220 millionths; it comprised several small penumbral spots. By the 18th there was a slightly larger penumbral spot at the following part of the group.  However, this spot had decayed by the 19th to give a Dai group with an area of 80 millionths.  This group continued to decay as it passed the central meridian, such that on the 22nd only a single Hax spot remained and on the 23rd an Axx spot.  This group was not seen on the 24th.  Also on the 18th only a Bxo group at 4°S/140°, AR 957, was seen.  Observations on the 24th and 25th showed blank disks.

Hydrogen Alpha:

On the 1st and 2nd filaments and plage associated with AR 953 were seen. On the 20th a double arch prominence on the SW limb was seen while on the 22nd a spike prominence on the NE limb which was the tallest prominence observed from 7 observations made during the month.

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June 2007

On the 2nd two groups were seen on the eastern portion of the solar disk: AR 959 as a Bxo group at 10°S/206° and AR 960 as an Eac group at 6°S/176°.  By the following day AR 959 has disappeared and AR 960 had moved further way from the limb to reveal an Ekc type group where there were several irregularly shaped penumbral spots. Its areas was estimated to be 590 millionths.  On the 4th this group was now of type Eac with a slightly reduced area of 490 millionths and by the 5th it was still of type Eac but with an area of 290 millionths.  By the 8th, with the group just past the central meridian it consisted of just two small penumbral spots and several surrounding spots and it was of type Dsi with an area of 90 millionths. By the 10th it has lost the surrounding spots to leave a Dso group with an area of 70 millionths. When next on the 12th all that remained was a single Hsx spot and it was last seen close to the western limb on the 13th.  On the 5th only AR 958 was seen at 12°S/226° as an Hsx spot.

A spotless disk was observed between the 15th and 23rd inclusive.  On the 25th an Hsx group, AR 961, had appeared around the eastern limb at 9°S/222°.  It has an estimated area of 120 millionths when seen on the 28th.

Hydrogen Alpha:

Although prominences were observed on each of the 12 observations made during the month, none were particularly striking - on the 8th, 9th and 10th the same prominence was seen on the SE limb which was shaped like an arch prominence on the 9th. Perhaps the tallest prominence seen during the month was on the 18th when a spike prominence was seen on the NE limb.

Most of the filaments seen during the month were associated with AR 960 as it progressed across the solar disk. Plage was also seen around AR 960.

On the 2nd a short lived flare was seen close to the eastern limb and to the SE of AR 960 between 16h 15m and 16h 25m.

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July 2007

On the 1st AR 961 at 9°S/221° was close to the central meridian as a type Cao group with an area of 70 millionths.  By the 3rd just a single Hsx spot was seen which was also the case on the 4th, 6th and 7th when it was close to the western limb.  On the 1st only an Axx spot was seen at 8°S/194° (AR 962).

A Dso group was seen close to the eastern limb on the 8th. This group, AR 963 at 4°S/58°, developed into an Ekc group by the 10th with an area of 370 millionths.  The main spot was the asymmetric leader penumbral spot which was followed by several smaller penumbral and other spots.  On the 11th this group was seen with the protected naked eye.  By the 12th the group started to decay through a reduction in the size of the leader and the number of follower spots.  On the 15th the group had an area of 150 millionths and it was of type Cso by the 17th.  It was last seen as a single Hsx spot close to the western limb on the 19th. On the 14th and 15th the only northern group of the month, AR 964, was seen further to the west from AR 963 having developed on the disk since the 12th.  It was of type Cso at 4°N/85° on both dates with an area of 40 millionths.

Observations between the 20th and 22nd plus on the 24th and 26th showed a spotless disk.  On the 28th an Axx spot at 9°S/198° was seen (AR 965).  This spot was still visible on the 30th when a Axx group comprising two spots was seen further to the west at 7°S/270°.

Hydrogen Alpha:

On the 6th a 'smoking chimney' type prominence was seen on the SE limb where the 'smoke' part extended some 5° along to solar limb (towards the south).  On the following day, at 16h 45m UT, a very bright prominence was also seen on the SE limb but closer to the equator. Later, at 17h 55m UT, the prominence was not quite as high above the limb but it was still as bright. The disk adjacent to the prominence also seemed bright. It was not seen on the following day, the 8th, but the sunspot group AR963 had appeared on the disk. This group was seen in Hα as it crossed the disk (although the extent and brightness of plage faded as it did so).  Two sets of nearby flame type prominences were seen on the SE limb on the 19th.  Towards the end of the month the size and number of prominences reduced.

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August 2007

Observations on the 1st to 3rd showed spotless disks.  On the 12th only an Axx spot was seen at 5°N/28° (AR 968). There were spotless disks for observations on the 13th, 16th and 17th.  The next observation on the 25th showed a Hax spot at 5°S/188° with an area of 70 millionths (AR 969).  As this sunspot progressed across the disk it was accompanied by other spots to make the group type Cao.  On the last day of the month this group was seen nearing the western limb.  On the 30th and 31st AR 970 was seen as an Axx type group at 6°S/121°.

Hydrogen Alpha:

On the 16th a striking prominence was seen on the NW limb which had the appearance of an airport wind sock.  It was still present on the following day but it had split into several parts. The 17th also had a total of 7 prominences which was the most seen of any of the 9 Hα observations made during the month.  The other prominence of note during the month was seen on the 27th on the NW limb – it consisted of two nearby spike type prominence to gave a ‘v’ appearance.  Several filaments were seen progressing across the disk between the 25th and 30th when they were close to the western limb.

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September 2007

Only three small groups were seen during the month.  On the 1st AR 969 was seen at 5°S/188° as an Hsx spot close to the western limb (it was not seen on the 2nd) together with AR 970 of type Bxo at 6°S/125° and near the central meridian.  AR 970 was seen again on the 2nd and 3rd but not the 4th and again on the 5th when it was still of type Bxo. No further spots were seen until the 29th when AR 971 developed on the disk at 4°N/114° as an Axx group consisting of 5 spots.  It was also seen on the 30th with the same number of spots.

Hydrogen Alpha:

Prominences were seen on each of the 11 days of observations when the number varied between 1 and 5.  The largest of these was on the 22nd when a spike prominence was seen on the NE limb.  Filaments were seen on just 6 of the days.  Plage was seen around AR 971 on the 29th.

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October 2007

Only one small sunspot group was seen during the month.  On the 6th only AR 972 was seen as with a mean location of 5°S/21° as a Bxo group consisting of two small spots near the central meridian.

Hydrogen Alpha:

Although prominences were seen on each of the 8 days of observations most were small. Exceptions were a spike prominence on the NW limb on the 13th and prominence in the shape of a spire on the SW limb on the 14th.  A more complex prominence was seen on the NW limb on the 27th and finally several nearby spike prominences were seen on the NW limb on the 31st. No significant filaments were observed during the month.

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November 2007

Two small sunspot groups were seen during the month.  On the 6th AR 973 was seen as with a mean location of 7°S/20° as an Axx group consisting of one sunspot (this being at the same location as AR 972 seen on the 6th October).  It was not seen on the next observation on the 9th. On the 16th a Bxo group, AR 974, had developed on the disk close to the central meridian at 13°N/203° (it was not seen on the previous day). It was not seen on the next observation on the 19th.

Hydrogen Alpha:

Observations on the 4th and 6th had low prominence activity.  On the 9th, however, a total of 6 prominences were seen on the eastern and western limbs – one of these was quite striking as it appeared like a ‘cumulus cloud’ on the SE limb. A gap could be seen between the bottom of the ‘cloud’ and the solar limb. The next other 4 observations of the month showed fewer and smaller prominences, with just one being seen on the 16th. More prominences were seen again on the 21st including a small bright prominence on the NW limb which faded within 5 minutes of first being observed.  Plage could be seen around AR 974 on the 16th.

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December 2007

On the 1st a Bxo group was seen at 8°S/332° (AR 976) which had disappeared by the following day.  On the 2nd and 3rd AR 977 was seen as an Axx group at 4°S/292°. The next observation on the 11th revealed a more substantial group approaching the central meridian.  AR 978, at 8°S/225°, was of type Dsc with the leading penumbral being the largest sunspot within the group with many small penumbral and other spots following. The total area of this group was estimated to be 170 millionths. Following observations showed that some of the following penumbral spots had merged, such that on the 15th the group was of type Dkc with the largest sunspot being at the following part of the group.  The total area had increased to 340 millionths. The size and number of spot reduced on the 16th when the group was nearing the western limb.

The five observations made between the 19th and 29th all showed a blank disk.

Hydrogen Alpha:

The most striking prominence from nine observations was seen on the 3rd when a curved spike prominence was seen on the NE limb. Other prominences seen were small with the most being seen on the 1st (seven) and the least on the 19th (one).   Plage could be seen around AR 978 on the 15th and16th.

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Last updated on 30 March 2007.