Affiliation
American Association of Variable Star Observers (AAVSO)
Wed, 12/07/2022 - 20:19

Today 2022/12/07 UT 12.10 I observed 8 groups, one of which is between 3156 e 3157 (3 spots), but it is not reported. Before posting it, I wanted your opinion. 

Maurizio

Image removed.

Zurich classification

Hi Maurizio,

Counting groups is sometimes difficult. One thing the AAVSO subscribes too though is the Zurich Classification scheme. 

https://www.aavso.org/zurich-classification-system-sunspot-groups

I counted only 5 groups yesterday and that was because I considered AR3157 as one large group. Using the Zurich class of E for that large group. Rather than 'split' the group as the NOAA classifiers often do. Please look over the Zurich Classes when thinking about your group splitting and counting of sunspots. 

Here is another good reference on counting from SILSO:  https://www.aavso.org/sites/default/files/solar/Sunspotandpores.pdf

from this web page: https://www.aavso.org/what-are-sunspots

Rodney (HRHA)

 

Affiliation
American Association of Variable Star Observers (AAVSO)
Hi Rodney,

ok, so I can use…

Hi Rodney,

ok, so I can use the Zurich classification to identify and count the groups: AR3156 and AR3157 as you said belong to type E and I count it as one group. AR3153 should also be of type E. Same thing for AR3159 and AR3160: single group D or E Zurich.
To measure the distance in degrees between groups, which method do you use? At the moment I don't take photo and I don't observe in projection.
Thanks for the links, which I will read with interest

Affiliation
American Association of Variable Star Observers (AAVSO)
Groups

Maurizio -

 

If you can figure out where the sun's equator is on a given day, it is very helpful, as the main spots within a group are ROUGHLY parallel to the equator (they can be tilted by several degrees aka Joy's law). Groups tend to sprawl much more in longitude than latitude, and big groups can be very 'spawly' in longitude. 3157 is a sprawly group that extends from one big spot off to smaller spots that are some number of degrees of longitude away, but the difference in latitude isn't that great.

LKR

 

 

Affiliation
American Association of Variable Star Observers (AAVSO)
I'm trying to develop my own…

I'm trying to develop my own method, which corresponds with the historical continuity of AAVSO visual data. Each association has its own, so my (many!) questions are used to remove any doubts I have, since I've read conflicting things. As mentioned for the counting of the groups I'm studying the Zurich classification.
To find the equator of the Sun I use both the ephemeris (Bo, P, Lo), and some software such as TiltingSun and Helio.
Last question: I have a Maksutov-Cassegrain 127/1500 with Astrosolar filter wide open. Unfortunately the seeing varies between P-F, should I diaphragm the telescope to have less turbulence?
Thanks
Maurizio

Zurich vs. McIntosh classification

Hi Maurizio,

I think you are referring to the McIntosh classification system: 

https://www.researchgate.net/publication/309428017_Flare_Production_Potential_Associated_with_Different_Sunspot_Groups/figures?lo=1

mcintosh solar classification

The McIntosh method is more complex than the Zurich classification scheme which the AAVSO has adopted since 1949 with the Shapley method using k - factors: https://iopscience.iop.org/article/10.1086/126109/pdf

Mostly folks use an aperture of less than 100mm to help with steading of the atmosphere. Can you reduce the aperture of your telescope? That is if you decide to submit data with the Zurich method? 

Also, to get a k - factor you will need at least 100 observations, mostly for consistency in your method. 

Rodney

 

 

 

Affiliation
American Association of Variable Star Observers (AAVSO)
Zurich vs. McIntosh classification

Hi Rodney,

I wrote Zurich because in your last post you said that the AAVSO subscribes to this system and I thought that this should be used for the historical continuity of the data.
I ask you for help in managing the method to use, summarizing my setup and the data that I have been transmitting via SunEntry for a month:
1) Mak/Cas 127/1500 telescope with Astrosolar filter and soon I will combine it with the wratten #21.
2) the data that I send to the AAVSO are: g, s, w, ng, sg, ns, ss.
Should I use the Zurich or McIntosh classification? If I decide to reduce the aperture <100mm does it change anything?