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W. Alpers et al.
Fig. 11.3 Photograph taken from the space shuttle Challenger at 11:45:57 UTC on 8 October 1984
(STS 41-G mission) showing sea surface signatures of a cyclonic eddy in the Mediterranean Sea
adjacent to the Egyptian coast. The center point of the photograph is at 31.5
◦ N, 27.5
◦ E. Visible on
the right Cape Alan el Rum. The eddy with a diameter of approximately 40 km lies in the outer sun
glint region, where lines of reduced sea surface roughness (caused by surface films) are imaged
dark
is determined by the critical angle which depends on the viewing geometry, i.e. on
the relative elevation and azimuth angles between the sun and the sensor, and also
on the sea surface roughness (Jackson and Alpers 2010). The photographs depicted
in Figs. 11.1, 11.2 and 11.3 were taken by the astronaut-oceanographer Paul ScullyPower with a Hasselblad camera with a focal length of 250 mm during the Space
Shuttle Challenger mission 41-G, which lasted from 5 to 13 October 1984 (ScullyPower 1986). During the times when the photographs shown here, always calm
wind conditions prevailed with wind speeds below 2 ms
−1 . Figure 11.1 shows a
photograph of the Mediterranean Sea near the Egyptian coast, which were taken at
12:02:55 UTC on 7 October 1984 (orbit: 33, roll: 35, frame: 95).
W. Alpers et al.
Fig. 11.3 Photograph taken from the space shuttle Challenger at 11:45:57 UTC on 8 October 1984
(STS 41-G mission) showing sea surface signatures of a cyclonic eddy in the Mediterranean Sea
adjacent to the Egyptian coast. The center point of the photograph is at 31.5
◦ N, 27.5
◦ E. Visible on
the right Cape Alan el Rum. The eddy with a diameter of approximately 40 km lies in the outer sun
glint region, where lines of reduced sea surface roughness (caused by surface films) are imaged
dark
is determined by the critical angle which depends on the viewing geometry, i.e. on
the relative elevation and azimuth angles between the sun and the sensor, and also
on the sea surface roughness (Jackson and Alpers 2010). The photographs depicted
in Figs. 11.1, 11.2 and 11.3 were taken by the astronaut-oceanographer Paul ScullyPower with a Hasselblad camera with a focal length of 250 mm during the Space
Shuttle Challenger mission 41-G, which lasted from 5 to 13 October 1984 (ScullyPower 1986). During the times when the photographs shown here, always calm
wind conditions prevailed with wind speeds below 2 ms
−1 . Figure 11.1 shows a
photograph of the Mediterranean Sea near the Egyptian coast, which were taken at
12:02:55 UTC on 7 October 1984 (orbit: 33, roll: 35, frame: 95).