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The Journal of San Diego History Observations of Joaquin Velázquez de Leon from Real de Santa Ana, June 3, 1769. Museo Naval, Ministerio de Marina, Madrid, Spain. According to previous estimations, the first contact of Venus with the Sun was to occur at 16:02:24 local time. We set a Meade ETX-70 portable telescope with a 70 mm aperture and a 350 mm focal distance. On this instrument we mounted a homemade “solar funnel” in order to project the disc of the Sun over a high contrast plastic screen. The plastic material slightly reduced the sharpness of the image when projected over the screen. It allowed, however, a comfortable observation of the Sun without having to constantly look through an ocular. This device was similar to others used in observations by the public in Baja California. We also filmed the observation with a video camera. The video did not allow a clear recognition of the first contact at the estimated time, but we noticed the start of the immersion at 16:03:02, when a small notch was visible in the disc of the Sun. The second contact was affected by the “drop effect” described by the eighteenth-century observers, and we had to wait to observe a “slice of light” between the edges of the disks of Venus and the Sun, as described by Velázquez in his journal. We registered complete immersion of Venus at 16:20:20, less than half a minute after the estimated hour for the contact at 16:19:55. Even though our instrumentation was not optimal, it was a very Photograph of the transit of Venus from San Diego, June 5, 2012. Courtesy Rueben H. Fleet Science Center. 282
The 2012 Transit of Venus Photographs by Carlos Román and Xavier López atop the 912m observatory hill showing (above), on the horizon, the Bahía de la Ventana and Isla de Cerralvo, towards Northwest; and (below) cloud profile over the Pacific Ocean towards West. 283
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