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Solar Observations for August 2017

Once again very low activity on the Sun continued throughout most of August. On the 1st only a single Cri (6) group could be seen close to the SE limb in AR12670. This was the only group of Sunspot on the Sun until the 12th when it was about to rotate round the wester limb as a single Hsx (10) spot.

It was not until the 15th that a new Csi (12) group was observed close to the NE limb in AR12671. By the 17th it had grown quite large to a CV (Classification Value) of Eai (23). This again was the only Sunspot group on the solar disc until the 20th by which time it had grown to a CV of Fki (48). It was joined on that day by a small Cso (11) group close to the NE limb in AR 12672.

By the 24th the group in AR 12671 had grown to a CV of Cko (38) and the group in AR 12672 had grown to Eki (47).

On the 27th the only group of Sunspots that could be seen was the Cso group in AR 12672 .

On the 29th two new groups were observed, an Hsx spot in AR 12673 and a Csi (12) group in AR12674 which proved to be an increase in Sunspot activity.

By the 31st four groups were observed, these included the Csi group in AR 12672, a Hsx spot in AR 12673, a Eko (44) group in AR 12674 and a Dki group in AR12675.


Most Prominence activity remained fairly constant though mostly faint. On the 5th a Broken Arched Prominence reached a height of about 102,000km.on the NE limb.

A faint Single Arch prominence on the 6th reaching 74,000km high, another Pyramid Prominence on the 17th also reached approximately 74,000km.

A Hedgerow Prominence joined with a Single Arch Prominence on the 23rd reached a height of 56,000 km


Only one type 1N Flare was observed for the month on the 19th. It started at 21.40, peaked at 21.50 and ended at 22.35; it had an X-ray class of C-7


For the month of August 2017 all activity once again on the Sun remained very low.

A total of 27 Observations were made for the month with the remaining days being cloud covered and/or rain.

A total of only 6 groups were observed. This included 3 groups in the north and 3 in the south, comprising of 31 spots in the north and 6 spots in the south.

The average Relevant Sunspot number for the month was 22 and the average CV was 33.3.

Most Prominences observed once again were quite faint.

Monty Leventhal OAM



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