Thursday, 9 July 2009

The Cycles of the Moon - Aluna


The fascination with the moon had for a long time now had a bit of low. It is just there on the sky changing somehow a bit everyday and might get recognized in good weather conditions at full moon.
Historically the lunar calendar had a big influence, today the only real lunar calendar is the Islamic calendar or Hijri calendar (wiki). Most calendar in the past where in fact lunisolar. “All these calendars have a variable number of months in a year. The reason for this is that a year is not evenly divisible by an exact number of lunation, so without the addition of intercalary months the seasons would drift each year. This results in a thirteen-month year every two or three years.” (wiki)
The lunar cycles are not in sync with our currently used time units. The lunar day is not 24 hours, but 24 hours and 50 minutes. The most visual impact of this shift is the tide cycle and the fact that the tide is not everyday at the same time, but is roughly 25 minutes later every day.
Aluna now, is a large-scale permanent installation to visualize and communicate the lunar cycles. It is proposed to be built in London in the East India Dock Basin by 2012.
“Aluna is a unique proposal for the world’s first tidal powered Moon Clock. It will change the way we consider time and understand our planet.
Larger than Stonehenge, Aluna’s forty meter wide, five storey high structure is made up of three concentric translucent recycled glass rings. By looking at how each ring is illuminated, you can follow the Moon’s movements, its current phase and the ebb and flow of the tides. This animation of light is called Alunatime.” (alunatime.org)
Three rings of glass will display the wax and the wane of the moon in 29.5 calendar days (largest ring), the rise and sink of the moon in 24 hours and 50 minutes (middle ring) and the ebb and flow of the tide in 6 hours 25 minutes (smallest ring).
A brilliant animation of the sculpture is on the website. It is a 3D rendering, but in sync with the three rings are also displayed the tide of the river Thames and the moon on the sky, absolutely amazing.
For lunar geeks, there is also a Google Gadget for your iGoogle displaying the lunar calendar.

aluna01.AxzswGKdVPFG.jpg
Image taken from aluna.org by Laura Williams