English: This radar image of
Dublin in Ireland, shows how the radar distinguishes between densely populated urban areas and nearby areas that are relatively unsettled. In the centre of the image is the city's natural harbour along the Irish Sea. The pinkish areas in the centre are the densely populated parts of the city and the blue/green areas are the suburbs. The two ends of Dublin Bay are
Howth, the D-shaped peninsula near the upper right side of the image, and
Dún Laoghaire, at the end of the C-shaped bay to the south. The small island just north of Howth is called
Ireland's Eye, and the larger island, near the upper right corner of the image is
Lambay Island. The yellow/green mountains in the lower left of the image (south) are the
Dublin and Wicklow Mountains. The large lake in the lower left, nestled within these mountains, is the
Poulaphouca Reservoir along the
River Liffey. The River Liffey, the
River Dodder, and the
River Tolka are the three rivers that flow into Dublin. The straight features west of the city are the
Grand Canal and the three rivers are the faint lines above and below these structures. The dark X-shaped feature just to the north of the city is
Dublin Airport. The image shows the coast from the town of
Skerries in the north to the bulging headland called
Bray Head in the south.
The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture (SIR-C/X-SAR) when it flew aboard the space shuttle Endeavour during the
STS-59 mission on 11 April 1994. This area is centred at 53.3 degrees north latitude, 6.2 degrees west longitude. The area shown is approximately 55 kilometres by 42 kilometres (34 miles by 26 miles). The colours are assigned to different frequencies and polarizations of the radar as follows: Red is L-band horizontally transmitted, horizontally received; green is L-band vertically transmitted, vertically received; and blue is C-band vertically transmitted, vertically received. SIR-C/X-SAR, a joint mission of the German, Italian, and the United States space agencies, is part of NASA's Mission to Planet Earth.