Relative Sunspot Number Observed from 2002 to 2011 at ButterStar Observatory
The ButterStar Observatory at the Dongducheon High School has been working for photographic observations of the Sun since October 16, 2002. In this study, we observed the Sun at the ButterStar observatory for 3,364 days from October 16, 2002 to December 31, 2011, and analyzed the photographic sunspo...
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| Format: | Article |
| Language: | English |
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The Korean Space Science Society
2012-06-01
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| Series: | Journal of Astronomy and Space Sciences |
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| Online Access: | http://ocean.kisti.re.kr/downfile/volume/kosss/OJOOBS/2012/v29n2/OJOOBS_2012_v29n2_103.pdf |
| _version_ | 1797331536292347904 |
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| author | Sung-Jin Oh Heon-Young Chang |
| author_facet | Sung-Jin Oh Heon-Young Chang |
| author_sort | Sung-Jin Oh |
| collection | DOAJ |
| description | The ButterStar Observatory at the Dongducheon High School has been working for photographic observations of the Sun since October 16, 2002. In this study, we observed the Sun at the ButterStar observatory for 3,364 days from October 16, 2002 to December 31, 2011, and analyzed the photographic sunspot data obtained in 1,965 days. The correction factor Kb for the entire observing period is 0.9519, which is calculated using the linear least square method to the relationship between the daily sunspot number, RB, and the daily international relative sunspot number, Ri. The yearly correction factor calculated for each year varies slightly from year to year and shows a trend to change along the solar cycle. The correction factor is larger during the solar maxima and smaller during the solar minima in general. This implies that the discrepancy between a relative sunspot number, R, and the daily international relative sunspot number, Ri, can be reduced by using a yearly correction factor. From 2002 to 2008 in solar cycle 23, 35.4% and 64.6% of sunspot groups and 35.1% and 64.9% of isolated sunspots in average occurred in the northern hemisphere and in the southern hemisphere, respectively, and from 2008 to 2011 in solar cycle 24, 61.3% and 38.7% of sunspot groups and 65.0% and 35.0% of isolated sunspots were observed, respectively. This result shows that the occurrence frequency for each type of sunspot group changes along the solar cycle development, which can be interpreted as the emerging and decaying process of sunspot groups is different depending on the phase of solar cycle. Therefore, it is considered that a following study would contribute to the efforts to understand the dependence of the dynamo mechanism on the phase of solar cycle. |
| first_indexed | 2024-03-08T07:36:52Z |
| format | Article |
| id | doaj.art-1d81ca459f874cb49457696a9d3ef51c |
| institution | Directory Open Access Journal |
| issn | 2093-5587 2093-1409 |
| language | English |
| last_indexed | 2024-03-08T07:36:52Z |
| publishDate | 2012-06-01 |
| publisher | The Korean Space Science Society |
| record_format | Article |
| series | Journal of Astronomy and Space Sciences |
| spelling | doaj.art-1d81ca459f874cb49457696a9d3ef51c2024-02-02T18:38:05ZengThe Korean Space Science SocietyJournal of Astronomy and Space Sciences2093-55872093-14092012-06-0129210311310.5140/JASS.2012.29.2.103Relative Sunspot Number Observed from 2002 to 2011 at ButterStar ObservatorySung-Jin Oh0Heon-Young Chang1Butterstar Observatory, Dongduchen High School, Dongduchen 483-707, KoreaDepartment of Astronomy and Atmospheric Sciences, Kyungpook National University, Daegu 702-701, KoreaThe ButterStar Observatory at the Dongducheon High School has been working for photographic observations of the Sun since October 16, 2002. In this study, we observed the Sun at the ButterStar observatory for 3,364 days from October 16, 2002 to December 31, 2011, and analyzed the photographic sunspot data obtained in 1,965 days. The correction factor Kb for the entire observing period is 0.9519, which is calculated using the linear least square method to the relationship between the daily sunspot number, RB, and the daily international relative sunspot number, Ri. The yearly correction factor calculated for each year varies slightly from year to year and shows a trend to change along the solar cycle. The correction factor is larger during the solar maxima and smaller during the solar minima in general. This implies that the discrepancy between a relative sunspot number, R, and the daily international relative sunspot number, Ri, can be reduced by using a yearly correction factor. From 2002 to 2008 in solar cycle 23, 35.4% and 64.6% of sunspot groups and 35.1% and 64.9% of isolated sunspots in average occurred in the northern hemisphere and in the southern hemisphere, respectively, and from 2008 to 2011 in solar cycle 24, 61.3% and 38.7% of sunspot groups and 65.0% and 35.0% of isolated sunspots were observed, respectively. This result shows that the occurrence frequency for each type of sunspot group changes along the solar cycle development, which can be interpreted as the emerging and decaying process of sunspot groups is different depending on the phase of solar cycle. Therefore, it is considered that a following study would contribute to the efforts to understand the dependence of the dynamo mechanism on the phase of solar cycle.http://ocean.kisti.re.kr/downfile/volume/kosss/OJOOBS/2012/v29n2/OJOOBS_2012_v29n2_103.pdfSunsunspotssunspot observationdata analysis |
| spellingShingle | Sung-Jin Oh Heon-Young Chang Relative Sunspot Number Observed from 2002 to 2011 at ButterStar Observatory Journal of Astronomy and Space Sciences Sun sunspots sunspot observation data analysis |
| title | Relative Sunspot Number Observed from 2002 to 2011 at ButterStar Observatory |
| title_full | Relative Sunspot Number Observed from 2002 to 2011 at ButterStar Observatory |
| title_fullStr | Relative Sunspot Number Observed from 2002 to 2011 at ButterStar Observatory |
| title_full_unstemmed | Relative Sunspot Number Observed from 2002 to 2011 at ButterStar Observatory |
| title_short | Relative Sunspot Number Observed from 2002 to 2011 at ButterStar Observatory |
| title_sort | relative sunspot number observed from 2002 to 2011 at butterstar observatory |
| topic | Sun sunspots sunspot observation data analysis |
| url | http://ocean.kisti.re.kr/downfile/volume/kosss/OJOOBS/2012/v29n2/OJOOBS_2012_v29n2_103.pdf |
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