Visiting Astronomers:

Baily, Francis
Dixon, Jeremiah
Elkins, W
Johnson Manuel
Mason, Charles
Newcomb, S
Wales, William

Mason and Dixon

Two English Astronomers, Charles Mason and Jeremiah Dixon were on their way to Bencoolen in Sumatra to observe  the 1761 transit of Venus. Their ship was delayed so they did their work at Cape Town instead.  The transit was successfully observed from Concordia Gardens, a social club that used to be behind  St Mary’s Cathedral in Cape Town. In 1772 Wales and Baily used the same site to do observations in Cape Town.

Mason and Dixon, became well known for their land survey between Maryland and Pennsylvania (U.S.A.), known as  the “Mason and Dixon line”. This line was surveyed to settle legal squabbles between the two states. During the American Civil War this line came to represent the dividing line between the slave owning and non-slave owning states (Confederates and Yanks)

Mason, Charles:

Dixon, Jeremiah:

Sources: – Mason and Dixon

Remaining Artefacts:

Bibliography:
Koorts, W.: The 1882 transit of Venus: The British expeditions to South Africa; MNASSA April 2004, Vol. 63 nos. 3 & 4, pp. 34 – 57.
Laing, J.D. (ed.), The Royal Observatory at the Cape of Good Hope 1820  – 1970 Sesquicentennial Offerings.
Moore, P. & Collins, P., Astronomy in Southern Africa, p  (General  Source)
Smits, P., A Brief History of Astronomy in Southern Africa. (Unpublished)

Wales and Baily

Two English Astronomers, William Wales and Francis Baily accompanied Captain Cook on his second voyage in 1772. They set up their telescope in Concordia Gardens, a social club that used to be behind St Mary’s Cathedral in Cape Town-close to the spot used for this purpose by Mason and Dixon.

Wales, William:

Baily, Francis:

Also known as Bayly
Born: 1774
Died: 1844

Famous for:
-He  first observed the phenomena that became known as “Baily’s  Beads”.  It can be observed during a total eclipse of the sun.
-President of the Royal Astronomical Society.

Sources: – Baily

Remaining Artefacts:

Bibliography:
Laing, J.D. (ed.), The Royal Observatory at the Cape of Good Hope 1820  – 1970 Sesquicentennial Offerings.
Smits, P., A Brief History of Astronomy in Southern Africa. (Unpublished)

Elkins W L (later Dr.)

Elkins was an American student who stayed in Strasbourg. He came to Cape  Town in January 1881 to pay Sir David Gill a short visit. He ended up staying for 2 years and 4 months. He helped Sir David Gill with heoliometer parallaxes measurements of nine southern stars, including Alpha Centauri. (Pioneering work as this was the first ever systematic measurement).Elkins worked with the Dun Echt Heliometer.

Sources: – Elkins

Bibliography:
Moore, P. & Collins, P., Astronomy in Southern Africa, pp.74 – 75.
Koorts, W.: The 1882 transit of Venus: The British expeditions to South Africa; MNASSA April 2004, Vol. 63 nos. 3 & 4, pp. 34 – 57.

Johnson Manuel

Johnson: Manuel John
Manuel John Johnson was a Lieutenant in the St. Helena Artillery and had been appointed by the British East India Company to be in charge of the Observatory on St. Helena Island. To gain experience he visited Fearon Fallows at the Cape Observatory from 29 December 1825 until 5 March 1826 and again from 12 September 1828 until 7 March 1829, during the opening ceremony of the Cape Observatory. He helped Fallows with pendulum experiments.
He produced a valuable catalogue in southern stars in which he acknowledges the help of Fallows in the introduction. This catalogue earned Johnson the Gold medal of the Royal Astronomical Society in 1835. Johnson was also Radcliffe Observer at Oxford, 1839 – 59.
Johnson noticed that Alpha Centauri has a large relative movement in Space. That means it must be close to Earth. When Henderson visited him at St Helena, he mentioned the fact to Henderson. This conversation led Henderson to measure the first stellar distance by parallax method (to Alpha Centauri), but he did not publish it.  Friedrich Bessel measured the distance to 61 Cygni and published it first.

Sources: – Manuel

Bibliography:
Warner, B., Astronomers at the Royal Observatory Cape of Good Hope.

Newcomb Simon (Prof)

1835 – 1909

Newcomb was an astronomer at the US Naval Observatory (USNO), and became the most honoured American astronomer of the 19th century – a crater on the Moon was even named after him.

With the 1882 Transit of Venus America decided to send an expedition under the leadership of Newcomb to South Africa. Gill originally suggested Beaufort West as an observing site. When Newcomb heard about the American connection with the Huguenot Seminary at Wellington he decided to go there instead.

At Wellington Newcomb’s party had fine weather and reported after the Transit that “all our observations were successful”. William Harkness reduced the observations and obtained a value very close to the accepted modern value. However, Newcomb (as well as Gill) were early critics of the Transit of Venus method to determine the Sun-Earth distance. He also spent a large proportion of his career studying the motion of the Moon and measuring the speed of light. In 1896 he adopted an extensive system fo astronomical constants, which was still in use well into the twentieth century. Newcomb received the Bruce Medal in 1898.

Sources: – Newcomb

Simon Newcomb, 1935 – 1909.
Credit: Dick 1988: p.243 Source: MNASSA Vol. 62, Nos. 6 & 7, August 2003, p.199

Bibliography:
Koorts, W.: The 1882 transit of Venus and the Huguenot Seminary for Girls; MNASSA October 2003, Vol. 62 nos. 7 & 8, pp. 198 – 211.
Koorts, W.: The 1882 transit of Venus: The British expeditions to South Africa; MNASSA April 2004, Vol. 63 nos. 3 & 4, pp. 34 – 57.