Sunspots and Solar Phenomena Jake Sarrantonio, Eddie Janicki, John Samson, Jon Germano

1. Sunspots and Solar PhenomenaJake Sarrantonio, Eddie Janicki, John Samson, Jon Germano Astronomy and Cosmology Spring2004 Quarter Project. • A sunspot is an area seen as a dark spot, in contrast with its surroundings, on the photosphere of the Sun. Sunspots are concentrations of magnetic flux, typically occurring in bipolar clusters or groups. They appear dark because they are cooler than the surrounding photosphere. Larger and darker sunspots sometimes are surrounded (completely or partially) by penumbra The dark centers are umbra. Observations Observations were originally done with the Sunspotter, The Sunspotter is an amateur tool that made accurate observations difficult. The idea of the Sunspotter in practice is excellent but due to the rotation of the Earth, the object falls out of the field of view very quickly and readjustment controls are non existent making it necessary to manually move the whole unit to keep the sun in the needed position to make drawings from. After two weeks of observation with the Sunspotter, We received the solar filter we had ordered. At that time, during early May, people we’re purchasing solar filters in record numbers to be prepared for the transit of Venus on June 8th. The solar filter fits on the end of the Meade ETX 125ec telescope. We took pictures through the telescope with a Minolta X-370 SLR camera. We chose Ilford Delta 100 film for its high resolution and low graininess. The biggest difficulty was the weather leaving gaps of days between sessions where usable data was obtained. The surface of the Sun is characterized by millions of vertical cells, called granules, of gas rising and falling. Hotter gas rises in the middle of the cells,while cooler gases fall at the edges. • Sunspots appear as small dark areas on the Sun’s brilliant surface. • They were first recorded more than 2000 years ago by the Chinese. • Because they are so large and prominent Sunspots became a take off point for the study of solar phenomena. Granules pushed onto their sides, the penumbra. Fig 1.5 Courtesy of www.astronomy.gr • Sunspots are observed to move across the solar surface from East to West and generally last from several hours to several months • Sunspots generally form in pairs with one spot leading and the other following. • Right now the number of Sunspots on the sun is decreasing as we move towards a sunspot minimum predicted to be in the vicinity of 2007 Umbra Granules Fig 1.7 Courtesy of Royal Swedish Academy of Sciences http://www.solarphysics.kva.se/NatureNov2002/press_images_eng.html Fig 1.6 Courtesy of Meade Solar Flares  A Solar Flare is a sudden release of energy and mass, created by magnetic fields from Sunspots, twisting and braking. Flares give off intense an amount of radiation in the covering the spectrum from radio waves to X-rays. X-class flares are big; they are major events that can trigger planet-wide radio blackouts and long-lasting radiation storms. M-class flares are medium-sized; they generally cause brief radio blackouts that affect Earth's polar regions. Minor radiation storms sometimes follow an M-class flare. Compared to X- and M-class events, C-class flares are small with few noticeable consequences here on Earth. Solar Flares are best observed from orbital platforms that are not shielded by the Earth’s atmosphere and can detect X-rays. From Earth flares are observed by using a filter that isolates light from Hydrogen Alpha as it is the best element to observe in the visual spectrum for Sun Flares. Effects of Sunspots on Earth When the Sun is very active it generates a large number of Sunspots, in turn causing a large amount of charged particles between the Earth and itself. This effectively causes the thickening of the Van Allen Belts, and as a result the lower atmosphere is shielded from cosmic radiation, thus less radioactivity occurs on Earth. Conversely at times of low solar activity, when there are few if any Sunspots, there fewer ions between the Earth and the Sun to shield cosmic rays . Therefore, lower solar activity creates more radioactivity on Earth. Periods of high solar activity, large numbers of sunspots, correlate exactly with the growth of powerful and sophisticated civilizations. Low sunspot activity seems to be linked with Dark Ages, which are marked by the general decline in the level of cultural achievement that has also coincided with the fall of civilizations. • The observed Sunspot cycle last 11 years corresponding to the Sun’s 22 year magnetic cycle. • As the cycle progresses towards the Sunspot Maximum, Sunspots show up closer and closer to the equator. • Sunspots cycles are best illustrated by the “Butterfly Diagram.” As shown below. Fig. 1.2 &1.3In these photographs, both the penumbra and umbra are visible. Fig. 1.2 &1.3 Acknowledgements First and foremost: Our Teacher, E.J. Zita, the CAL staff, and anyone else we forgot to mention Images: 1.1 taken from, http://spacescience.spaceref.com/ssl/pad/solar/images/bfly.gif 1.2&1.3 produced by our team. 1.4 taken from Mayan Prophecies Gilbert, Cotterell 1.5 taken from www.astronomy.gr 1.6 taken from www.meade.com 1.7 taken from Royal Swedish Academy of Sciences http://www.solarphysics.kva.se/NatureNov2002/press_images_eng.html Data: Aveni, Anthony The Sky in Mayan Literature Oxford University Press 1992 Cotterell, Maurice Astrogenetics, Brooks Hill, 1988 Stix, Michael. The Sun: an Introduction. New York: Springer-Verlag. 1989 Kaufman, & Freedman. Universe sixth edition. New York: W.H. Freedman and Company. 2002 Gribbin, John. Blinded by the Light. New York: 1991 Menzel, Donald Howard, Our Sun. Revised edition. Cambridge, Harvard University Press, 1959 Our Data During the course of the project we accumulated 18 images of the sun 5 photographs and thirteen drawings from the Sunspotter. After unsuccessfully trying to calculate the rotation of the sun do to missing data from poor weather, and dealing with a 3 dimensional object with 2 dimensional images. Preventing us from calculating rotation with any spots near the edge, and the missing data made our calculations worthless. Fig. 1.1 http://spacescience.spaceref.com/ssl/pad/solar/images/bfly.gif Fig. 1.4 Mayan Prophecies Gilbert, Cotterell