![]() "Galileo's sunspot letters to Mark Welser". "John of Worcester spot on with his 1128 sun diagram". One can look directly in the telescope in that case and draw the sunspots whilst looking at them. One less accurate way to do this is to buy the special filter for blocking the light from the Sun. When the Sun is projected, there are two ways for drawing sunspots: you can project Sun on the screen, look at it and draw sunspots on the table, but you can also project the Sun on the drawing paper, just mark the position and draw the shape. ![]() For 10 inch telescope, the optimal distance of the screen from the eyepiece is 1–1.5 meter. The further the screen, the bigger the image, but also less bright, so one has to find the perfect proportion. The easiest way to draw sunspots is to project the image of the Sun to the screen. There are two ways of drawing sunspots: projection and direct viewing. But for better viewings of the sunspots one needs a telescope with 8 inches of diameter or more. With a pinhole and a screen one can produce an image of the Sun. On the white acid-free paper, they draw a circle with solar coordinates and draw and mark sunspots. However, in modern times, the drawers became very accurate and sunspot drawing became art sometimes they needed many hours to complete work. The early drawers did not draw their shapes and positions very accurately because they wanted just to mark where the sunspots were on the magnetic data. The Mount Wilson observatory started drawing sunspots by hand in 1917. The first drawing of sunspots by Mount Wilson Observatory, Ferdinand Ellerman, January 4, 1917 Probably, he was never looking at the Sun directly through the telescope. In the same year, his student Benedetto Castelli invented a new method for observing and drawing sunspots, the projection method. ![]() He Probably never observed them in the middle of the day. He complained that he couldn't observe the Sun every morning and evening because of low clouds and so he couldn't see their motion with confidence. ![]() It is also possible, that he was referring to Scheiner's observation, where he first saw that the Sun is rotating. From there it seems that he observed the Sun at sunset, but not at sunrise because of the high horizon of Apennines. He said, "The spots seen at sunset are observed to change the place from one evening to the next, descending from the part of the sun then uppermost, and the morning spots ascend from the part then below. It seems like he was observing the Sun and drawing sunspots without any filter, which is very hard. In his telescope, he saw some darker spots on Sun's surface. In 1612, Galileo Galilei was writing letters on sunspots to Mark Welser. Five days later, the Korean astronomer saw the northern lights above his country, so this is also the first prediction of coronal mass ejection. His drawing seems to come around solar maximum. There are records of observing sunspots from 28 BC, but that is the first known drawing of sunspots, almost 500 years before the telescope. Sunspots were probably first drawn by an English monk John of Worcester on 8 December 1128. Their prediction is very important for radio communication because they are strongly associated with solar activity, which can seriously damage radio equipment. Sunspots are darker spots on the Sun's photosphere. Sunspot drawing or sunspot sketching is the act of drawing sunspots. The first sunspot drawing, John of Worcester around 1128 For broader coverage of this topic, see Solar observation.
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