Explanation:
From solstice to solstice,
this six month long exposure
compresses time
from the 21st of June till the 21st of December, 2011,
into a single point of view.
Dubbed a solargraph,
the unconventional picture was recorded with
a pinhole camera made from
a drink can lined with a piece of photographic paper.
Fixed to
a single spot for the entire exposure,
the simple camera continuously
records the Sun's path each day as a glowing trail
burned into the photosensitive paper.
In this case, the spot was chosen to look out
over the domes and radio telescope of
the University of Hertfordshire's
Bayfordbury
Observatory.
Dark gaps in the daily arcs are caused by cloud cover,
whereas continuous bright tracks record glorious spells of sunny weather.
Of course, in June, the Sun trails begin higher
at the northern hemisphere's summer solstice.
The trails sink lower in the sky as December's
winter solstice approaches.
Last year's autumn was one of the balmiest on record in the UK,
as the many bright arcs in the lower part of this picture
testify.
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