A Cooke and a Transit in Mauritius

 

A Cooke and a Transit in Mauritius

The transit of Mercury was observed on November 14^th 1907 from the Royal Alfred Observatory in Mauritius using a Cooke 6inch refractor. The transit which was seen through a cloudy sky and the limb of the Sun was described as being boiling. Mercury appeared as a clear cut black disc, perfectly circular with no spot or fringe.

There were 11 photographs taken during the transit with the 6 inch Cooke which had been supplied to Mauritius by the colonial government in1874 in order to observe the transit of Venus.

The Astronomy Show tonight 7.00 pm- 9.00 pm

 

The Astronomy Show 7^th September 2020 7.00 pm - 9.00 pm

On the Astronomy Show tonight I will be looking at what can be seen in the sky during the next seven evenings. There will be the latest astronomy news, I will be looking at the types of stars in the sky. I will continue with the A-Z of Constellations and the Messier Marathon plus the astronomical anniversaries for this week.

The Astronomy Show 105.3FM only on Drystone Radio can be heard live on line at www.drystoneradio.com if you cannot listen live then the show can be heard on the Drystone Radio podcast for the next 30 days.

Astrognome 100 Great Stars No 23 Castor

 

Castor

Alpha Gemini, Castor which means the ‘Horseman’ is one of the twin sons of Zeus and Leda in Greek mythology, the other is Pollux and the pair form a prominent pair just over 4 degrees apart, Castor is slightly fainter than Pollux.

In classical Greek Castor and Pollux were often identified with St Elmo’s fire which can be seen in the riggings of ships, it is electrical discharges during storms. It was always seen by sailors as omens of good luck helping the mariners to safely reach port.

Castor can be seen as a star of magnitude 1.9 and is 51 light years away, and it is an A3 class star hotter than the Sun. Castor appears to the naked eye as a single star bit in fact it is a star system made up of no less than 6 stars.

Castor was probably seen as a double star as early as 1678 by Cassini there is also a faint red dwarf star which is part of the system it is a variable star with the designation of YY Gemini. And just to complicate the situation even further each of these three stars is a double itself which explains why there are 6 stars in the Castor star system

Comet Borelly and the Isaac Roberts Cooke Telescope

 

Comet Borelly and Isaac Roberts

Discovered on the 21^st July 1903 by M Borelly at the Marseilles Observatory the comet would become an easy naked eye object at magnitude 2.5 it was observed until August 24^th when it became to close to the Sun to be seen.

Isaac Roberts at Crowborough, photographed the comet the top and bottom photographs of the comet were taken using his 5 inch Cooke telescope while the middle one was taken with his 20 inch reflector.

During the time the comet was in the sky the weather was poor and when the weather was clear the Moon was near full making photography difficult. That sounds a bit like the weather today!

Comet perrine and The Isaac Roberts Cooke Telescope

 

Comet Perrine and The Isaac Roberts Cooke Telescope

On August 31^st 1902 Charles Perrine at the Lick Observatory in America discovered a comet, this was Comet b 1902 Perrine. It was discovered in the constellation of Perseus.

The comet was photographed by Isaac Roberts using his 5 inch Cooke telescope. Roberts made a series of 5 photographs of the comet between September 6^th and October 10^th. This is an example of one of those photographs.

He also photographed comet Perrine 6 times using his 20 inch reflector.

Isaac Roberts began his astronomical career in 1878 at Rock Ferry on the Wirral Peninsular using a 7 inch Cooke telescope, in 1882 he moved to Maghul near Liverpool and in 1890 he moved to Crowborough in East Sussex where he observed comet Perrine.

Astrognome 100 Great Stars No 22 Capella

 

Capella

Capella is the most northerly of the first magnitude stars. In brightness it is virtually equal in brightness to Vega which occupies the overhead point in summer a position that is occupied by Capella in winter.

Capella or alpha Aurigae is the brightest star in the constellation of Auriga the Charioteer, it is also the 6^th brightest star in the sky. In mythology Auriga is said to represent Erechthonius, son of Vulcan, the blacksmith of the gods who invented the four horse chariot.

Capella means the ‘She-Goat’ and just below Capella is a triangle of three stars called the kids a very prominent feature of the winter skies and a sure sign that the star you think you are looking at really is Capella.

Capella is a G3 yellow giant star lying at a distance of 43 light years. In 1899 astronomers discovered that Capella is a double star , the second star referred to as Capella b is also a yellow giant star. The two stars orbit each other every 104 days. There is also a pair of red dwarfs that orbit at a distance of around about 1 light year.

Over the years it was thought that there were five other stars in the Capella system, however astronomers have now discovered that these stars are merely line of sight stars and are not connected with Capella.

Capella also appears to be one of the brightest sources of X Rays in the sky, this is thought to come from Capella a.

Thomas Cooke and the BBC TV Antiques Road Trip

 

Thomas Cooke and the BBC TV Antiques Road Trip

Yesterday I participated in filming an episode of the BBC TV Antiques Road Trip as a guest 'expert' talking about the instrument maker Thomas Cooke of York.

There was four hours of filming for about four minutes of TV!! As far as I am aware it is due to be aired sometime next year. It was great fun but quite tiring.

The filming was undertaken at the York Castle Museum in their Victorian Street where there is a ‘T. Cooke & Sons’ shop front. We also filmed at the York Observatory in the Museum Gardens where there is a 4.5 inch Cooke telescope.