Ancient Stone Age buildings served as a star calendar

Function of Europe's oldest monumental buildings in Austria revealed

Rising of the Pleiades in the gate of the Kreisgrabenanlage Immendorf © University of Vienna
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Around 50 circular grave sites in Lower Austria are among Europe's oldest monumental buildings: they were built between 4, 800 and 4, 500 BC. Built and used - for what, is not yet clear. However, one of the many hypotheses about their role in the life of Stone Age people has now been confirmed by Viennese scientists: some of the buildings apparently served as sun or star calendars.

According to the researchers, in an ongoing project all well-known circular trench installations are to be examined with regard to this "calendar function".

Stonehenge was later

Stonehenge was still in its infancy at the time of the Middle Neolithic circular trench installations in Lower Austria. The complex monumental buildings surrounded by a deep moat were erected about 2, 000 years before the famous British stone circle.

However, from a more transient material: wood. Weather and millennia-long agriculture have long since blurred their tracks in the landscape. Nevertheless, one can enter the enigmatic buildings today - and virtually: A team around the archaeologist Wolfgang Neubauer and the astronomer Georg Zotti of the Interdisciplinary Research Platform Archeology (VIAS) of the University of Vienna has the Stone Age circular trench 1: 1 recreated on the computer.

Not only archaeological excavations and magnetic prospecting carried out in 2003 and 2004, but also the simulation of the starry sky 6, 500 years ago are used for these virtual reconstructions. Because in their research project "ASTROSIM" Neubauer and Zotti want to show through the combination of archaeological and astronomical data by means of computer simulation that the circular trench systems served in addition to the assumed socio-cultural and religious functions as a kind of stone-age calendar. display

Virtual reconstruction of the Kreisgrabenanlage Steinabrunn University of Vienna

Neolithic calendar?

For a possible social or religious use of the buildings, such as a place for meetings or competitions, transition and initiation rituals or certain festivals in the annual cycle, speaks according to the researchers that between 4, 800 and 4, 500 BC Every settlement in Lower Austria has a circular ditch plant called " in something like today every Lower Austrian village has a church or a club house, " explains Neubauer.

That the orientation of the gates could be linked to the rising or setting of the sun, moon, or stars on certain days of the year - a hypothesis that has been under discussion since the beginning of the scholarly exploration of monumental buildings in the 1970s The archaeologist at first thought it unlikely: "In Lower Austria we have almost 50 circular trench layers with gates in all possible directions - I thought, there it happens that there is always something up or down somewhere

Arch astronomical computer simulation

This is where astronomy comes into play: to underpin the calendar thesis - or finally falsify it - Zotti first had to recalculate the starry sky with the help of astronomical computer programs: "The position of the stars shifts over the centuries, says the astronomer.

In the run-up to the project, he has already examined 28 plants - and found surprisingly significant similarities: About one third of the buildings each have two gates in exactly the same direction.

Starting signal for the spring sowing?

For some of these gates, Zotti's astronomical and Neubauer archaeological data have already been combined in the computer animation. The result was clear: one of the gates marks the rise of the seven-star (Pleiades), the other the almost simultaneous sinking of the star Antares.

This event is especially interesting as a so-called "heliacal sunrise" in the early morning, just a few days after the start of the spring. "If the sky gave 'green light' for the spring sowing? speculates Zotti. Other gates apparently mark, as previously stated, striking sunrises and underpings, such as the solstices.

Sleeping three more times, then celebrating

The people could then figure out how many sunsets are missing until the next big party, Neubauer describes another possible function of the calendar. For the archaeologist continues to argue that suitability as a solar or star calendar is only an addition to the actual socio-cultural significance of the systems: If it had only been a question of determining data, If two patches were left in the ground, both scientists agree.

(idw - University of Vienna, 16.06.2009 - DLO)