The course of the sun
tate-of-the-art instruments for observing the universe meet ancient camera technology. This unusual image was taken by D. López Calvin and J. C. Muñoz Mateos with a pinhole camera. To do so, the two photographers from the European Southern Observatory ESO exposed the image for about eight months.
The tall structure in the foreground is the "seeing monitor," which measures the twinkling of stars due to atmospheric turbulence. The domes in the center left are part of the Very Large Telescope, and the one on the far right belongs to the VLT Survey Telescope.
The bright colored lines were produced by the Sun moving across the sky during the day, leaving a trail on the photographic paper in the pinhole camera. The camera was facing west, so we see hundreds of sunsets here. But as the Earth moves around the Sun, the Sun sets at a different point on the horizon each day. The shortest arc on the far right of the image corresponds to the winter solstice, when the sun reaches its lowest position. From this point on, the sun moves southward day by day, to the left in this image. The arcs become longer and higher. Then, at the summer solstice, the sun reaches its highest point, which is not visible in this image, and draws the longest arc to the left.
The dark lines are due to clouds darkening the sun. Fortunately for astronom:ers, the Paranal Observatory has more than 300 clear days a year, hence the few dark streaks in this image.
Welcome to Photonworld – a platform for knowledge, interesting facts and science on the topic of light. Photonworld aims to provide a basic understanding of the physics of light and its countless phenomena. From medicine, to art and physics: all topics are covered.
Photonworld originated as an initiative of the excellence cluster the Munich-Centre for Advanced Photonics (MAP) and the Laboratory for Attosecond Physics (LAP) at the Max Planck Institute of Quantum Optics (MPQ).
The initiator of the project is Prof. Dr. Ferenc Krausz, Chair of Experimental Physics at the LMU and Director of the MPQ.
Photonworld’s Student Zone reports directly out of the PhotonLab, which is supported by the Munich Center for Quantum Science and Technology (MCQST) and the DFG Research Unit FOR 2783. At the PhotonLab, schoolteachers and students can find up-to-date information about experiments and goings-on at the lab, and plan their own visit to the laboratory.
