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Observation report
Observation hints


Who cares about a starless sky?

Oberserving the stars is becoming more and more diffucult due to the increasing sky brightening due to artificial lights. But not only astronomers notice the bright night sky. Many people only know the starry sky from their vacations. Bad ligthing is a waste of energy, is a safety and security risk du to glare and endangeres nocturnal animals.
Its goal is the worldwide determination of the present night sky visibility conditions based on simple astronomical observations that can be done with the naked eye and within minutes. The success of the experiment depends on obtaining as many observations as possible from as many locations as possible: that means your contribution! The date are collected and analysed by the the Verein Kuffner-Sternwarte and the Thüringer Landessternwarte Tautenburg.
Oberservers in the northern hemisphere:
We have selected two constellations for the experiment. Both are easy to find on the night sky. For observations north of roughly 30 degrees (Spain, Turkey, Arizona) the Little Dipper (Ursa Minor) is especially well suited, because it is visible all night an throughout the year.
During the winter months a second constellation is very practical for the determination of the night sky visibility conditions. It is the constellation of Orion. Orion is easier to locate on the sky because of its three conspicuous belt stars. As a results observers can chose between two constellations and/or compare the results between the two constellations.
How many stars can we still see in Vienna

Earth at Night
Astronomy Picture of the Day


Ursa Minor


Orion was also selected because the belt stars can be seen worldwide (but not year round), except for areas close to the north and south poles, where only parts of the constellation are visible.
Observers in the southern hemisphere:
To determine the night sky visibility conditions in the southern latitudes we selected the constellation of Orion. It is very easy to find --- the three belt stars are probably the easiest to find on the night sky. The only drawback is that it is not visible for the entire year and during some months only during parts of the night. We were not able to find a constellation like the Little Dipper, easy to find and visible all year, on the southern skies. With our home in the north we would be thankful for suggestions from the south.
FINDING CHARTS and more information on the visibility of the constellations!