Transit observations in History
Mason and Dixon are mentioned as having been
successful in getting good data from Cape Town - but, it seems that the ingress
was not actually visible from Cape Town - so they could not have got contact II?
There is another successful observer mentioned - Fr. Maximilian Hell of AUstria
- but, I do not yet have confiremed information whether he observed both ingress
and egress.
Does someone have a list of other successful observers from 1761 who timed both
ingress and egress?
Rathnasree
Rathna,You will find a very
extensive list of online resources on past Venus
transit expeditions and observations at
http://www.transitofvenus.org/historic.htm.
Mike Simmons
Thanks, Mike. I had looked at
this site some weeks ago, but, some new links
seem to have been added since, that are very useful. There is information I
am looking for that is still not available on this site though.
For Instance, there is a 1882 MNRAS paper that discusses all the useful 1761
and 1769 observations, which mentions many names not talked about, in these
links. Does this mean there is scope for someone to dig for information,
still? - Rathnasree
I have seen this quotation
attributed to Halley -
"This sight...is by far the noblest astronomy affords..."
Presumably attributed to a transit of Venus?
I am wondering which event he was actually referring to, considering he
lived between 1656 and 1742 and could not have witnessed a transit of
Venus!
Rathnasree
I don't know the source of the quote but it could
have been Halley despite
his never having witnessed such a Venus transit. Halley was not only very
interested in Venus transits because of their potential utility in
determining the length of the astronomical unit -- and thus the scale of
the solar system -- but he wrote about it in perhaps the most important
such paper ever published. In 1716 Halley published "A new Method of
determining the Parallax of the Sun, or his Distance from the Earth" in
which he set out the method of measuring the astronomical unit by parallax
during upcoming Venus transits, thus attracting the attention of
astronomers worldwide and providing the spark that set in motion the many
adventurous expeditions to observe the Venus transits of the 19th
century. A translation of Halley's paper from the original Latin can be
found at
http://sunearth.gsfc.nasa.gov/eclipse/transit/HalleyParallax.html.
I don't
find the quote in this paper but there may well be another by Halley where
it can be found. I think it's certainly plausible that the quote is
Halley's. Of course, it could just as well be someone else's, too.
Mike Simmons
Yes, ofcourse, Halley's paper underlay all the
preparations for the
1761 and 1769 transits, and he could have made the statement in
anticipation of the event and as an appreciation of its significance.
It is just that the 'is' in the quotation seems to refer to an
actually observed phenomenon.
Rathnasree
I see your point, Rathna. I don't believe that it necessarily implies
present tense, however, as though he made the remark during an
observation. Someone could say, e.g., "A total solar eclipse is an
awesome
natural phenomenon" at any time (and I often do!).
After failing to find the quote in Halley's seminal paper, however, I am
curious as to its source. It still could be someone else's or simply a
misquote. Perhaps someone on the group will have the answer.
Mike Simmons
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