Dark Night at the Height of White Nights
Full lunar eclipses occur when the Moon gets into the shadow of our planet – the Earth. They occur every year and are seen from the big territory, that is why they are observed more often than solar eclipses. But lunar eclipses are not always so interesting, as that one happened on the night of 16th of July 2011. The Moon crossed the centre of Earth’s shadow and hence the eclipse was rarely dark.
Novosibirsk amateurs were actively preparing to the observations of this eclipse. For choosing of place for observations it was needed to take into account the fact that the Moon during the eclipse will be situated very close to the horizon – below 10 degrees. The eclipse itself lasts more than three hours, during which the Moon shifts by 45 degrees along the horizon. Therefore there must not be big troubles for observations in the South. A part of observers, quite numerous, was located at the embankment of Ob river in the region of River-boat station. Observations were also kept in Akademgorodok on the roof of Novosibirsk State University.
Our group of about 20 men in quantity chose the area of building of new Novosibirsk Planetarium (Astrophysical Center) at Klyuch-Kamyshenskoe plateau for observations. The Planetarium itself is still being built – the first floor is being finished – hence the group was located not far from the building, at the building yard. As these were the first night observations at this location, at the same time it happened possible to check the influence of city illumination.
In the south direction lots of lights were seen – there dachas and cottages spread out along the Ob bank. Illuminated route, where is busy traffic even at night, is situated down the hill. However, it doesn’t hinder to make observations, because the trees, surrounding the territory, hide excessive illumination. There were some men, among the participants of our “outing”, who were involved with the Planetarium project from the very beginning – V.A. Skosyrskiy (City Administration), E.A. Lugovskaya (Siberian State Geodesic Academy), L.V. Parko (Central Design Bureau), the author of this note. We all made sure once again that the place, chosen as far back as in December 2006, was successful.
) Photo of the Moon in the moment of full eclipse |
The eclipse started between 12 p.m. and 1 a.m. At first, barely visible black discoloration arose on the left side of the full Moon. Observers had enough time to enjoy our satellite. The full Moon was very bright, especially if looking through the eyepiece of TAL-150K telescope. We had to set grey neutral light filter to lower its glitter. And the glitter started getting dim – the Earth’s shadow was covering the Moon slowly but steadily. For an hour the illuminated surface of the Moon was getting smaller and smaller, and the shaded side was filling with dark-crimson colour. This colour was developed specially well on photos with long exposure.
Then I understood the feelings of the Indians, from whom Columbus “stole” the Moon in a far year 1504. He knew about beginning of the lunar eclipse from ephemeris and he had to cheat the Indians to get food and water. Aborigines wanted the white overlord to return the night luminary in the sky and were ready to give him everything for it.
At 2 hours 22 minutes full phase began – the Moon became so dark that it was needed to stare at it to see it as a little spot. The stars around the Moon became visible. However, nights in June are short, so we hadn’t an opportunity to see the end of the eclipse. Besides, small clouds appeared in the sky. Between three and four o’clock observers started going home, having looked at the crimson discus in the clearing up sky and having heard the songs of the first birds.
) Present view of the future Planetarium |
This night astrophysical measurements of brightness of the lunar discus were also taken. For this purpose special device - luminance meter, provided by workers of CDB “Tochpribor”, was used. Every some minutes readings of lunar brightness were fixed. It was found out that the lunar brightness during the eclipse had reduced from 540 to 0,7 cd, i.e. almost in 800 times. Other observers confirmed that this eclipse in comparison to the earlier observed ones was very dark.
In conclusion I would like to congratulate the contributors of “People’s tribune” on anniversary of the newspaper and wish them further creative progress.
S.Yu. Maslikov, Head of Youth “Astrophysical Center”.
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