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Observation of Venus transit over the Sun disc on 8th June 2004
Early in the morning, we had to bring all necessary things for observation to the courtyard of our school, where the action took place. The start of this event had been announced by Hradec Králové observatory to take place at 7:20 am.
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The day before observation, on 7th June, we prepared all necessary items and put them into the physics cabinet in our school for easy access for the next day. These items included portable bulletin boards, which were used for extinguishig superfluous surrounding light. Their other function was as information-boards, where visitors could watch the printed documents from the web pages of the Hradec Králové observatory, informing them about this event. The most important tool, of course, was the telescope.
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We used a historical apparatus called 'Estigma' from about 1913. The diameter of the object lens of this telescope is 80mm and the focal distance is 150mm. For the figure of this event, we used a paper size A3, which we fixed on a board. The figure was screened. For shade, we used a black blanket, which covered the place between the bulletin boards and the telescope, where some light could leak through and obstruct the wonderful sight. We also needed a radio-controlled alarm clock, which we used to determine the accurate time during the observation.
Our effort to see the beginning of this event, was not possible, because of clouds. The first photo of the Sun with Venus, without clouds, was made at 8 o'clock am. From this moment until the end of the event, except a few short moments, we had a clear sky. The first curious fellows came a few minutes later. You can see them on the next photo. Many classes camw with their teachers, not only from our secondary school, but also from the neighbouring primary school.
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We acquainted small groups (usually about 5 or 10 people), with the most important datum about the Sun, Venus, this unique event, but also about the ways of observing the Sun and about dangers connected with observation. Some of them tried to watch the Sun through the special glass-filter from the Hradec Králové observatory or through two diskettes, which were free for use. In the sighting through the special filter, the hue of the Sun was green, and through the diskettes the hue of the Sun was red. Green has more contrast then red, so the Sun was seen better through the filter.
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During the whole day, we took photos catching the process of this effect, and also the many people, who visited. The best photos we took are in our gallery. The biggest problem was a strong and ugly wind, which often changed direction, and came in big gusts. And several times it happened, that out shield made from the bulletin boards fell, so we had to right it again. Fortunately we managed to fix it all with strings. You can see these on some photos. In the final phase of the effect, when Venus began to leave the Sun disc, the Sun was high on the sky, so we had to make better shading of observation place. As we could not see the beginning of this event, we were looking forward to seeing the final phase and pay the highest attention to it. We expected with tension the foreseen drop-effect and shiny aureole, which would be viewed around the border of Venus while leaving the Sun disc. The drop-effect we could see very well, but the shiny aureole only one of us saw.
After the end of this event we tidied the site and put the instruments back into the physics cabinet, where they are waiting for the next action. We are looking forward to observing the next phenomenon.
With translation of this document helped Leslie Ramier. Thanks!
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