Eton School and a Cooke

 

Eton School Observatory and Thomas Cooke

In 1870 one of the masters possible H G Madan at Eton School decided that they would provide a telescope. They chose a 5.9 in Thomas Cooke & Sons Refractor. The observatory was also made by Cookes. The observatory was erected on the roof of the western tower of the New Schools. It is square and surmounted by a revolving dome.

Although a telescope on a roof will never be completely free from vibration it is reduced to a minimum by supporting the telescope on two massive trussed iron girders stretching across the observatory. The floor is supported quite independently.

The telescope which was up the normal Cooke standards was supplied with the new Cooke clockwork driving system which was designed by the late Thomas Cooke.

The science master at Eton School was H G Madan who was the brother of Falconer Madan who was himself the grandfather of Venetia Burney who suggested the name Pluto for that newly discovered planet.

I believe that the Eton telescope is still in use today in a different observatory located next to Eton Golf Course and is used by the Herschel Astronomical Society.

Astrognome 100 Great Stars No 21 Canopus

 

Canopus

One of the loveliest stars in the sky which sadly cannot be seen from Britain. It is the second brightest star in the sky after Sirius. It is also a rather strange fact that the three brightest stars in the sky Sirius, Canopus and Alpha Centauri are all in the southern sky while the next three brightest ones Arcturus, Vega and Capella are in the North.

The fact that it could be seen from Alexandria but not Athens was one of the arguments put forward by Greek astronomers that the Earth must be round.

Canopus or alpha Carinae is the brightest star in the constellation of Carina the Keel. Canopus traditionally marked the rudder of the ship, which used to be part of the massive constellation of Argo Navis the ship that Jason used to look for the Golden Fleece. The constellation of Argo has now been broken up into four smaller groups.

The legendary Canopus was a character in the saga of the Trojan war, he was the pilot of the ship which carried King Menelaus home after the fall of Troy.

Canopus lies at a distance of 310 light years and is an A9 giant star with a surface temperature of around 7,300 degrees.

Canopus is used as a star tracker for space craft and was used in 1964 by Mariner 4 which was the first space craft to successfully fly by the planet Mars. Incidentally it also changed scientists’ views of what Mars might look like from close up.

Astrognome 100 Great Stars No 20 Betelgeux

 

Betelgeux

One of the most famous and most interesting stars in the sky. It is ranked as the 10^th brightest star in the sky, but although being labelled as alpha it is usually slightly below beta or Rigel in brightness. It is a variable star normally varying between 0.3 to 0.8, its a semi regular variable star with a variable period of between 400- 1,000 days. However during during 2019 and 2020 it became much fainter than normal and caused astronomers many headaches.

Betelgeux which is sometimes pronounced as quite unofficially as Beetlejuice, its name is Arabic and means the ‘Shoulder of the Central One’ and is a red supergiant star. In fact it is so big that if it was placed where our Sun is all the planets out to Jupiter would be inside the star, Betelgeux lies at a distance of about 700 light years. As it is very large and close to us astronomers can actually see a disk rather than just a dot. It is one of the largest stars that can be seen with the naked eye.

Betlegeux will become a supernova within the next million years which astronomically speaking is a very short period of time and as I mentioned earlier in 2019/20 it became very faint and fell to magnitude 1.7 well outside its usual range, and many astronomers believed it is was to go into its supernova phase and blow up and destroy itself. It took some expert astronomers some time to consult historical records which showed that this had it had faded in brightness back in 1927 and 1941.

Astronomers now think they understand what caused Betelgeux to become more fainter than normal, using the Hubble Space Telescope they saw a large amount of dense hot gas moving out from the star. This gas then may have cooled down and formed a dust cloud that partially blocked the light from Betelgeux reaching the Earth.

Betelgeux will become a supernova at some point in the future and you can be quite sure that astronomers with regards to what has just happened will be paying even more attention to this old red supergiant than they would normally do.

Can too many Cookes ruin a Transit?

 

Can too many Cookes ruin a Transit?

Well they can if the weather is poor.

The transit of Mercury on May 6^th 1878 was observed by many astronomers including Mr John Brett and Mr Walter Pye. Brett was using a 4 inch Cooke and Pye a 3 inch Cooke. The observations were made from Mr Brett’s observatory in Putney, near London.

Both first and last contacts were missed by impenetrable mist, it was then seen through a fine film of cloud. When Mercury could be seen as a black dot it was surrounded by a ring of bright light.

The clouds made observations difficult but whenever they were able to see Mercury it was surrounded by this ring. Due to the very large amount of cloud and observing conditions Mr Pye could only use a power of x50 on the 3 inch Cooke while Mr Brett using the 4 inch Cooke had to use rather less magnifying power on the 4 inch Cooke.

Astrognome 100 Great Stars No 19 Beta Pictoris

 

Beta Pictoris

Little did Nicolas de Lacaille know that his obscure southern constellation Pictor The Painter’s Easel invented in the 18^th century to fill a space between bright constellations would become famous for holding one of the sky’s most intriguing stars.

Beta Pictoris is outwardly just one more warm A6 spectrum star with a temperature of 8,000 degrees and shinning at a magnitude of 3.8, and is the second brightest star in the constellation of Pictor, beta lies at a distance of 63 light years.

Though seemingly ordinary beta is a vivid illustrator of the wonders that can be achieved with modern instruments. The key to the star’s fame lies not in what can be seen with the eye, but in the infra red.

Astronomer have discovered that beta is surrounded by a large disk of dust and gas. This was the first disk of dust and gas to be discovered around a star. There appears to be evidence of material that has formed into several asteroid belts and possibly comets. So far astronomers have identified two plants one discovered in 2008 and the other in 2019.

It is quite possible that by studying beta Pictoris astronomers can get a better idea of how our solar system formed around 4. 5 billion years ago.

Astrognome 100 Great Stars No. 18 Beta Lyra

 

Beta Lyrae

September 10^th 1784 was a night to remember in the city of York because Beta Lyrae was found to be variable by the deaf astronomer John Goodricke who was observing from the Treasurer’s House in the city. It was the same night that Edward Pigott also observing from the city of York on that same night discovered that eta Aquila was also a variable star. When I was Curator of Astronomy at the Yorkshire Museum in York I christened these two the ‘Fathers of Variable Star Astronomy’.

Until this night only 5 variable stars were known, yet these astronomers increased the number by 2.

If you look at the constellation of Lyra which is named after the musical instrument the Lyre you cannot fail to notice the bright star Vega which is overhead in summer nights as seen from Britain, it is one of the summer triangle stars. Just below Vega you will see a little parallelogram of four fairly bright stars.

Beta or to give its proper name Sheliak which means ‘Lyra’ varies in brightness between magnitudes 3.4 to 4.3 over a period nearly 13 days. Sheliak is not a single star, there are two stars, it is a binary system. We can only see one of the stars. The two stars are both B class stars much hotter than the Sun, the pair lay around 960 light years away.

The two stars are eclipsing each other in a very regular way. John Goodricke explained the variations of Beta Persei or Algol, by stating that there must be two stars eclipsing each other causing the light variations. He was of course quite right. Goodricke was not only able to identify Sheliak as a variable he also worked out its light range and period between maximum brightness. Goodricke thought that the light variations made the star appear similar to Algol.

The two stars are very different, Goodricke could not know that this system is very bizarre. The two stars are so close to each other that the gravitational pull from each star actually pulls them both out of shape. They are pulled into egg shaped stars. Astronomers refer to see stars as ellipsoidal variable stars. Beta Lyrae is the prototype for this class of variable star.

They Needed Cookes to build the Sydney Harbour Bridge

 

They Needed Cookes to build the Sydney Harbour Bridge

There had been plans to build a bridge across Sydney harbour since 1815 but nothing really happened in the 19^th century. Although there were plans to build a bridge in 1914 World War stopped all those ideas.

After World War 1 tenders were put out in 1921 for companies to put forward ideas for the bridge, in 1922 Cooke and Sons of York designed a new type of Level which would be used to help the engineers construct the bridge. This level enabled a difference in height of a quarter of an inch of any two lines at a dissonance of one mile to be determined.

This order was placed before Cooke and Sons became Cooke Troughton and Simms later in 1922.

Eventually in 1924 the Australian government awarded the contract to Dorman Long and Co Ltd of Middlesbrough who would also build the Tyne Bridge at Newcastle upon Tyne. The Sydney Harbour Bridge was formally opened in March 1932.

If you have ever been over the Sydney Harbour Bridge just remember that without the superb optical equipment of Thomas Cooke and Sons of York it would probably never have been built.