On 06/05/2012 12:48 PM, Taylor Roberts wrote:
> In getting ready for tonight's Transit of Venus, I wonder if SLC
> witnessed the previous pair in 1874 and 1882.

   We can immediately rule out the transit of 1874-12-09 if SLC was
anywhere on the American continents, as the transit was neatly and
precisely not visible from anywhere on the continent.  See:

   http://astro.ukho.gov.uk/nao/transit/V_1874/index.html

   The transit of 1882-12-06 was, however, visible from the Americas.

   If anyone has detailed information about SLC's whereabouts and
activities on the date in question, I can easily plot the circumstances
for the transit as he could have seen it.  I can do high-precision
calculations of astronomical phenomena.

   For example, if he were in Elmira, NY, (Lat. 42.0897 N, Long. 76.8081
W) the transit would have begun at about 9:04 AM EST, and finished at
about 3:05 PM EST.  Its closest approach to the center of the sun was at
12:04 PM EST.  It made a neat little arc along the "bottom" of the sun.
 It was a quite nice transit designed to last for a large fraction of a
short day of a cold winter month.

   If we know his daily activities on 1882-12-06 (note: this is ISO date
format.  It means December 6, 1882,) then we would be able to determine
if he could have seen the transit or not.  Does anyone have that
detailed information?

   Note that a transit of Venus cannot be seen with the naked eye, and
is hard to see with appropriate filters with the naked eye.  One is
better with a telescope (with appropriate solar filters.  I'll have to
research the state of the art of solar telescopy in 1882.)

-- 
  Alan Eliasen
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  http://futureboy.us/