Cooke Telescope Tales - occultation of Saturn observed from South Africa in 1920

 Occultation of a Star by Saturn on March 14^th 1920 made at Rondebosch, South Africa using a 6 inch Thomas Cooke telescope by W Reid, C. L O’B Dutton and W G McIntyre. 

 From the report that was received from South Africa it was assumed that many observers in the north would have seen this occultation but that does not seem the be the case. Due to this exact timings were not prepared. The report says that the star was not following its predicted path although I wonder if what they were really seeing was that Saturn was not quite in its predicted place. 

The time when the star was in contact with the rings was given as 8.46 South African Standard Time however this was a compromise. It was the time when the observers present were all certain that the star was behind the rings. Mr Reid thought it touched the rings 3 minutes earlier and at the time given was on the edge of Ring B 

At first their was very little loss of light, but as soon as it touched Ring B the light gradually faded for about a half a magnitude. It remained this way for a few seconds, when it fell a little further, and almost immediately the flicker took place – that is, the star suddenly almost went out, but not quite, it rose again fairly suddenly. After this its light fluctuated very considerably, but never reached more than a magnitude less than its original brightness. 

The star disappeared behind the planet at 8.54 and re appeared at 10.36. The seeing on the night was very good.

                                                     www.theramblingastronomer.co.uk

The Astronomy Show on Drystone Radio

 Join me, Martin Lunn MBE every Monday evening from 7.00 pm-9.00 pm on the award-winning Astronomy Show on Drystone Radio, probably the only regular astronomy show on any radio station in the country. 

I will take my weekly look at the night sky and look at all the latest news in astronomy. There will be the astronomical anniversaries this week plus the latest news from the astronomical societies in the north of England.

The Astronomy Show every Monday evening only on Drystone Radio live online at www.drystoneradio.com DAB radio in Bradford and East Lancashire, or 102 and 103.5 FM and can also be heard later on the Drystone Radio Podcast.

A little ramble through 19th century astronomy - aurora in 1874

Academy, Saturday 28^th February 1874

 Professor Domenico Cipolletti has drawn attention, in the Nazione, to the coincidence of the times of appearance and disappearance of the aurora borealis, seen at Florence on the evening of February 4, and those of the grand auroral display witnessed at the same spot February 4, 1872. The aurora was also seen at Milan and other parts of northern Italy on the 4th, on which evening strong magnetic disturbance was noted at the Vienna and Munich observatories. Professor Cipolletti exhorts observers to watch with special care for any manifestations of sudden light in Jupiter's belts, which have been proved by the observations of Lassell, Proctor, and others, to exhibit the brightest colours at those periods, in which the aurora borealis was most strongly marked.

                                                       www.theramblingastronomer.co.uk

Cooke Telescope Tales - telescopes for carlisle in 1857 and 1858

 In February 1857 William Day of Carlisle who was headmaster at the Christchurch Boys School in Carlisle purchased a 4.25 inch portable equatorial telescope. As this was early 1857 it could still be a Thomas Cooke of York telescope rather than a Thomas Cooke & Sons of York, because it was around this time that the company changed its name.

 He also  in early 1858 purchased a smaller 3.5 inch telescope also from Cookes.

                                                        www.theramblingastronomer.co.uk

Cooke telescope Tales - telescope for Manchester in 1860s

 Eddowes Bowman 1810-1869 was born in Nantwich in Cheshire and although he considered going into an engineering profession but his career took him into the field of classical literature. 

He became chair of Greek and Latin Classics and Greek and Roman History in Manchester New College. It was also at this time that he developed an interest in natural science. This included astronomy. 

In the early 1860s he purchased a 7.25 Cooke refractor in a specially constructed observatory. I do not know if the observatory was built by Cookes. Due to his many other interests it appears as if the telescope was little used. He died at Victoria Park Manchester. 

Born November 1810 died July 10^th 1869

                                                         www.theramblingastronomer.co.uk

Cooke Telescope Tales - T W Backhouse and two comets

On the 27^th September 1892 about 15hrs 30 mins GMT comet Brooks (c1892) had a tail 10 degrees long, pointing at an angle of 280 degrees. 

At the later part of September Swift’s comet (a1892) was still a conspicuous object seen with a 4.5 inch Thomas Cooke refractor. Observations on several nights showed that it not only has  a faint tail- at position angle 260 degrees on the 24^th September at 8hrs and 30 mins, when I observed it to be certainly 11 degrees long, and suspected it to 21 degrees- but that also there was an elongation nearly in the opposite direction.

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A little ramble thbrough the winter sky - Gemini the Twins

 An ancient constellation, Gemini a winter group represents a pair of twins holding hands. They are Castor and Pollux members of the crew of the ship Argo with Jason in search of the golden fleece. The fleece had come from a magic Ram which had been able to fly, after it died its fleece was placed in a sacred grove, guarded by a dragon which Jason killed, and he took the fleece back to his own country.

Castor and Pollux were of mixed parentage although both sons of Leda, Castor’s father was king Tyndareus of Sparta while the father of Pollux was the god Zeus. When Castor died, because he was mortal, Pollux begged his father Zeus to give Castor immortality, and he did, by uniting them together in the heavens.

Alpha or Castor at magnitude 1.9 is the second brightest star in Gemini lying 51 light years from Earth, Castor is an A class star with a temperature of around 10,000’c much hotter the Sun at 5,800’C. Although it appears to the naked eye as a single star there are in fact 6 stars that make up the Castor system

Beta or Pollux with a magnitude of 1.1 is the brightest star, Pollux is 34 light years away and is a K class orange giant star.

There is a minor mystery here because Ptolemy in the 2^nd century stated that Castor was brighter than Pollux whereas now it is the other way around, the Arab astronomers agreed with Ptolemy. So, if the old astronomers were correct we must suppose that either Castor has faded or else Pollux has brightened up. It seems more likely that the change would have occurred in Pollux.

Gamma or Alhena which means the ‘Shining One’ lies 109 light years away and is of magnitude 1.9, it is an A class star.

Eta or Propus which means ‘Forward Foot’ is a M class red giant star, Propus is a variable star and its brightness changes between 3.1-3.9 over a period of around 230 days. The star lies at a distance of about 320 light years.

Epsilon or Mebsuta which means ‘Outstretched Arm’ shines with a brightness of 3.1 and lies at a distance of 840 light years. It is a G class class supergiant star.

Delta or Wasat which means ‘Middle’ is a F class star lying at a distance of 60 light years away, It shines at a magnitude of 3.5. 

Zeta or Mekbuda which means the ‘Outstretched Left Leg, it’s a Cepheid variable varying brightness between magnitude 3.7 and 4.1 every 10.2 days,  Mekbuda is 1,200 light years away and varies between a F7 supergiant to a G class supergiant class star.

Mu or Tejat which means ‘Back Foot’ is 230 light years away and is a M class red giant star that varies very slowly between magnitude 2.7-3.0 in a period of around 70 days.

Messier M 35 is an open cluster around 3,800 light years away containing about 400 stars. M35 can be seen in the sky near eta as a magnitude 5.1 mottled splash of light. Charles Messier saw M35 in 1746.

                                            www.theramblingastronomer.co.uk

 

A little ramble through Indus the Indian

 Another southern hemisphere constellation created by Petrus Plancius in 1598 based on observations by Pieter Keyser and Frederick de Houtman while exploring southeast Asia. The constellation represents a native Indian although there is some confusion as to what Indian is being represented. It was introduced to stellar maps by Johan Bayer in 1603.

As in the case of many other modern constellations, Indus is very faint and it contains no really bright stars. The two brightest stars alpha and beta can be seen with the naked eye but any misty or haze would make them difficult to see.

Indus is similar to other modern southern hemisphere constellations in that it was unknown in Europe or the Middle East hence there is no old mythology attached to Indus.

Alpha has a magnitude of 3.1 and lies at a distance of 98 light years, the star is a K class giant star cooler than the Sun.

Beta is fainter with a magnitude of 3.7, another orange K class giant star lying 600 light years away.

There are no bright deep sky objects to be seen in Indus.

                                                       www.theramblingastronomer.co.uk

Cooke Telescope Tales - telescope to steel maker in Sheffield in 1858

 The steel manufacturer and merchant Charles Daniel Doncaster from Broomhall Park, Sheffield purchased from Thomas Cooke & Sons in 1858 a 3.25 inch telescope on a tall tripod, with steadying rods, finder, three astronomical eyepieces and one terrestrial pancratic eyepiece, plus vertical and horizontal slow motions, in a box. The cost was £33, today this would be over £3,300. 

                                                       www.theramblingastronomer.co.uk

The Astronomy Show on Drystone Radio

 Join me, Martin Lunn MBE every Monday evening from 7.00 pm-9.00 pm on the award-winning Astronomy Show on Drystone Radio, probably the only regular astronomy show on any radio station in the country. 

I will take my weekly look at the night sky and look at all the latest news in astronomy. There will be the astronomical anniversaries this week plus the latest news from the astronomical societies in the north of England.

The Astronomy Show every Monday evening only on Drystone Radio live online at www.drystoneradio.com DAB radio in Bradford and East Lancashire, or 102 and 103.5 FM and can also be heard later on the Drystone Radio Podcast.

A little ramble through 19th century astronomy - Vulcan

 The Observatory April 20^th 1877

Notwithstanding the incessant watch kept up for three days in various parts of the world, no news of the supposed planet has reached us; and according to M L Leverrier, we must now wait at least six years before another transit could possibly occur. Mr Pogson at Madras, after repeated searches in a remarkable pure sunset sky, concludes that no planet can exist in the position assigned.

                                                        www.theramblingastronomer.co.uk

A little ramble through astronomy in Yorkshire - Easter

 Yorkshire has a claim as to why the date of Easter changes each year, so there is no point in blaming  other people.

In 664 at Whitby Abbey it was decided to follow the teachings of Rome as to how to calculate the date of Easter. This means that Easter Sunday is the first Sunday following the full Moon after the Spring Equinox. And as the period of time it takes the Moon to orbit the Earth is roughly 29 days or one month which is in fact a modern word and comes from the old word ‘moonth’.  The date of Easter Day or Easter Sunday can be as early as March 22nd and as late as April 25th.

                                                         www.theramblingastronomer.co.uk

Cooke Telescope Tales - telscope for Rugby in 1858

 In 1858 C. Evan of Rugby purchased a 4.5 inch Thomas Cooke & Sons telescope. The telescope had a focal length of 78 inches. It was mounted on a fixed equatorial stand with clockwork motion, illuminating apparatus, micrometer with eyepieces, astronomical eyepieces £150 In 2026 this would be around £24,000. 

I don’t know if this is the Rev C Evans of Rugby who was elected a FRAS in 1858, or if he had any connection with Rugby school.

                                                        www.theramblingastronomer.co.uk

A little ramble through the winter sky - Auriga the Charioteer

 A striking constellation in the northern skies, Auriga lies above the horns of Taurus the Bull and forms the shape of a kite. Auriga is named after the son of Vulcan who invented the four horse chariot. Its brightest star Capella is the 6^th brightest star in the sky.

In 1899 astronomers discovered that Capella was not a single star but a double star. Like so many stars that appear single to the eye, Capella actually consists of two stars. But there's more going on with Capella as there is another component to this system, a pair of small red stars, meaning that where we see just one star there are actually 6!!

Capella whose name means the ‘Little She Goat’ has a magnitude of 0.1 and its a  G class giant slightly cooler than our Sun which is a G class dwarf and is 43 light years distant.

In brightness it is virtually equal to Vega in the constellation of Lyra the Lyre but it is of a very different colour, its yellowish tinge contrast sharply with the steely blue of Vega. Both are circumpolar from Britain, they can be seen all year round. They lie on opposite sides of the north pole star and at roughly the same distance from it. This mean that when Capella is high up Vega is low down and vice versa. From Britain Capella is overhead during winter evenings while in summer it is Vega that occupies that position. When at their lowest they are very low just above the horizon.

Slightly to the right and just below Capella is a little but quite distinct triangle of stars called the Haedi or the kids. They are referred to as the Kids because where the she goat goes the kids will always follow!! The top star in the triangle is epsilon, bottom left star is eta and the bottom right is zeta.

Epsilon is a F class supergiant white star its distance in not known with any great certainty but it could be about 2,000 light years away. It normally it shines at around magnitude 3.0 but every 27 years it fades to magnitude 3.8 where it remains for between 640–730 days – about two years. Epsilon is eclipsed by an unseen and unknown very large companion star.  The star’s last dimming was from 2009 to 2011.  The next should begin around 2038!

Zeta is another eclipsing binary where the companion star cannot be seen with the naked eye and varies between magnitude 3.7-4.1 over a period of 972 days.  Zeta is a K class giant star lying 790 light years away.

The third component eta which is 243 light years away. It is a B class star making it much hotter than the Sun, and has a brightness of magnitude 3.2.

Beta or Menkalinan which means ‘Shoulder of the Charioteer’, is the second brightest star in Auriga and is found to the left of Capella with a magnitude of 2.0 the same brightness as the North Star. It is an A class star with a surface temperature of around 9,000` C much hotter than our Sun. It lies at a distance of 82 light years.

A line drawn down from beta will reach the star theta or Mahasin with means the ‘Wrist of the Charioteer’. Theta has a magnitude of 2.6 and is an A class star 166 light years away. 

From eta which is the top star of the Haedi or kids a line drawn down and past zeta will come across iota or Al Kab which means the ‘Shoulder of the Rein holder’ at a distance of 490 light years we see iota as a star of magnitude 2.7. It is a K class giant being cooler than our Sun.

In 1930 for some reason the star that was originally classified as gamma Aurigae was transferred to the constellation of Taurus the Bull and re labelled at beta Tauri. It makes no sense at all as it is the bottom of the kite shape which used to form Auriga.

                                                      www.theramblingastronomer.co.uk

 

 

A little ramble through 19th century astronomy - Red Stars in 1874

 Academy, Saturday 7^th February 1874 

Mr. Birmingham, of Tuam, has lately been examining the red stars comprised in the list formed by Schjellerup some years ago, and has already communicated some interesting results to the Astronomische Nachrichten and Monthly Notices. He finds curious changes of brightness in some stars, whilst others have disappeared altogether; and his results are confirmed by observations made at the Royal Observatory, Greenwich.

The connection between colour and variability in stars is very curious. It would appear that the red stars are in the condition of a fire dying out, and that the embers are sometimes raised to a white heat by some unknown causes only to die down again in an equally mysterious, manner. We are much in the dark as to the how and the when of many of these changes, but this much we do know, that solid bodies become brighter as they become hotter, and in doing so pass from red through yellow to bluish white. But what is the behaviour of gases under such conditions, is a problem of the immediate future, and it must be remembered that the changes in stars are probably due to gases; so that we are hardly yet in a position to speculate.

 The interesting question remains, whether we can justify a division of variable stars into two classes, the one of short period (a few days), showing the phenomena of rotation or of the interposition of a dark satellite; the other of periods ranging from a month to many years, in which the change has a physical origin. The stars of the latter class are generally red.

                                                       www.theramblingastronomer.co.uk

The Astronomy Show on Drystone Radio

 Join me, Martin Lunn MBE every Monday evening from 7.00 pm-9.00 pm on the award-winning Astronomy Show on Drystone Radio, probably the only regular astronomy show on any radio station in the country. 

I will take my weekly look at the night sky and look at all the latest news in astronomy. There will be the astronomical anniversaries this week plus the latest news from the astronomical societies in the north of England.

The Astronomy Show every Monday evening only on Drystone Radio live online at www.drystoneradio.com DAB radio in Bradford and East Lancashire, or 102 and 103.5 FM and can also be heard later on the Drystone Radio Podcast.

 

Cooke Telescope Tales - telescope for Cambridge

 In 1867 William Henry Mandeville Ellis of St John’s College, Cambridge purchased a 4 inch Thomas Cooke & Sons telescope. I think that William Ellis was an architect. 

The telescope came with six astronomical, one comet, one eclipse and one terrestrial eyepieces. All the eyepieces had to be packed in a mahogany box.

                                                  www.theramblingastronomer.co.uk

 

 

A little ramble through Hydrus the Lesser water Snake

 Hydrus the Lesser water snake is located near the south pole and therefore cannot be seen from Britain. It was one of twelve constellations created by Petrus Plancius from the observations of Pieter Dirkszoon Keyser and Frederick de Houtman on their explorations of what would become the Dutch East Indies and today is Indonesia. The constellation first appeared on a 35-cm (14 in) diameter celestial globe published in late 1597 (or early 1598) in Amsterdam by Plancius and Jodocus Hondius. The first depiction of this constellation in a celestial atlas was in Johann Bayer's Uranometria of 1603.

This is a smaller southern hemisphere version of the great water snake, Hydra. Hydrus is sandwiched between the two Magellanic clouds and almost bridges the gap between Eridanus and the south celestial pole. The Magellanic clouds are two nearby galaxies that can be seen with the naked eye from the southern hemisphere.  As Hydrus is so far south it was not known to astronomers in Europe or the Middle East and therefore has no old myths or legends attached to it.  Unfortunately, Hydrus is not a very bright constellation.

The brightest star is beta with a magnitude of magnitude 2.8 lying at a distance of only 25 light years. Beta is a G class star.

Alpha is the second brightest star with a magnitude of 2.9, its a F class star lying at a distance of 72 light years.

Located mostly in Dorado the Goldfish, the Large Magellanic Cloud also extends into Hydrus.

There are no bright deep sky objects in Hydrus

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A little ramble through Yorkshire Astronomy - The Devils Arrows at Boroughbridge

We stay with pre historic sites but move from features in the earth to standing stones. Keeping the North Yorkshire theme we travel to a site near Boroughbridge in the Harrogate district. We move forward in time to about 2,000 BCE to discover the Devils Arrows a line of three huge stones sometimes called ‘the three sisters’ there are suggestions that originally there were four stones.

The stones which are made from millstone grit which is  believed to have been quarried at Knaresborough which is around seven miles away and then dragged to their present positions. The stones each weigh around 25 tons so moving them using the technology available 4,000 years ago was no mean feat.

The stones that are still standing are aligned southeast to northwest and they form a line 374 metres long. The stones are between five to six metres high and are sunk into the ground to a depth of about 1.5 metres. The Devils Arrows today are actually less than 200 metres from the A1M motorway.

The name the Devils Arrows only dates back to the 1700s when according to legend the devil threw the stones at the next town which is Aldborough however much to the annoyance of the devil the stones fell short of their intended target and landed near Boroughbridge instead! I am not sure what a town in Yorkshire did to get the devil so annoyed?

As with many of these standing stones across the country there almost certainly was an astronomical connection. I am not sure if anybody is certain just what the connection might be. It certainly is not as clear cut as with the Thornborough Henges and the link with Orion. The fact that they align southeast to northwest suggests a possible link with the Sun and Moon. If as astro-archaeologists believe that there were originally four stones at this site it  could suggest a connection  with the position of the Sun and Moon during the four seasons during the course of the year. I am afraid that as with many of the stone circles and standing stones we will probably never know for certain.

The Devils Arrows like Thornborogh Henges are also listed as Scheduled Ancient Monuments.

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A little ramble through the winter sky - Canis Minor the Lesser Dog

 In mythology it is the smaller of the dogs that follows Orion the Hunter.

 It has only one bright star alpha or Procyon which means ‘Before the Dog’, this is because it rises before Sirius. Procyon is the 8^th brightest star in the sky with a magnitude of 0.3. It is close to the Earth being only 11.5 light years away. It is an F class star meaning its slightly hotter than our Sun.

Procyon forms a very prominent and large triangle with Sirius in Canis Major and Betelgeuse in Orion. This is often referred to as the Winter Triangle.

By a remarkable coincidence both of the dog stars are accompanied by white dwarfs. The pup orbiting Sirius was discovered by Alvan Clark in 1862 when he was testing a new telescope. The white dwarf orbiting Procyon was discovered in 1896 at the Lick observatory using the 36 inch refractor.

White dwarfs are the remains of a star that has used up all its hydrogen fuel and what remains is mostly helium, this makes them super dense objects with a tea spoon weighing many tons.

The only other notable star is beta or Gomeisa which means the ‘Bleary Eyed One’ It is of magnitude 2.9 and is 160 light years away, its a B class star which means it is hotter than the sun.

                                                     www.theramblingastronomer.co.uk

 

 

Cooke Telescope Tales - telescope for London in 1858

 Sir Thomas Cunningham of Eaton Place Belgrave Square London purchased in 1858 from Thomas Cooke & Sons a universal 3.5 equatorial telescope. Later in 1859 he purchased from Cookes an equatorial mounting with tangent screw motion on a tripod for the latitude of Great Britain.

                                                        www.thramblingastronomer.co.uk

A little ramble through 19th century astronomy - observations of stars in March 1866

 Astronomical Register March 1866 

Sir, I shall be glad if you would accord me space in the register for the few following remarks. 

Between 21^st and 28^th February 1865 the atmosphere here was unusually steady. There was scarcely any limit to the magnifying power which the stars bore. 

Antares. On the morning of the 22nd, 27^th and 28^th, the companion was distinctly visible with my Cooke’s 4.5 inch refractor before and up to sunrise, free from the light of the large star. The green colour for the companion was in fine contrast with the brilliant red of the large star. 

Lambda Ophiuchus. 4, 6, dist. 1.16” according to the Leyton observations, was clearly separated on the mornings of the 25^th, 27^th and 28^th. 

Psi2 Orion. 5.11.5 dist 2.95” (Knott). On the evening of the 26^th the small star was occasionally quite free from the rings of light around the large star, a minute but bright point. 

Trapezium The fifth star has been generally very distinctly visible, and on several nights the sixth, though it has appeared to me minute in comparison to the fifth. 

Eta Orion. My Object glass fails to separate this close double star. The fine state of the atmosphere has enabled me to use very high powers, which show the two stars wedged together or overlapping, but without dividing them. 

I have also seen distinctly the components of 15 Pleiadum, 8,14, dist. 5”, and the 15^th mag companion to Beta Aquarius. 

Sun Spots. On the 28^th February a feature was visible which I have never before seen so distinctly. A brilliantly luminous band boarded the f side of a small spot which followed the large spot.  Another spot of some size followed the small spot at a little distance. I observed this one with one of Dawes’s eyepieces and powers from 90 tom 300, with glasses of different tints. Other details in the spots were at times beautifully defined. It is probable that this spot and luminous band were observed in England with instrument of larger aperture. 

I am, Sir, your obedient servant,  

D A Freeman

Mentone, Alpes Maritimes: Feb 7^th 1866

                                                     www.theramblingastronomer.co.uk

 

 

The Astronomy Show on Drystone Radio

 Join me, Martin Lunn MBE every Monday evening from 7.00 pm-9.00 pm on the award-winning Astronomy Show on Drystone Radio, probably the only regular astronomy show on any radio station in the country. 

I will take my weekly look at the night sky and look at all the latest news in astronomy. There will be the astronomical anniversaries this week plus the latest news from the astronomical societies in the north of England.

The Astronomy Show every Monday evening only on Drystone Radio live online at www.drystoneradio.com DAB radio in Bradford and East Lancashire, or 102 and 103.5 FM and can also be heard later on the Drystone Radio Podcast.

Cooke Telescope Tales - Planets observed from India in 1870

The Rev J Spear observed Jupiter, Saturn and Mars in 1870 from Chukrata N W Provence's, Bengal using a Thomas Cooke & Sons 4.5 inch telescope. 

He also observed double stars using a Barlow lens more than doubling the telescopes powers.

                                                        www.theramblingastronomer.co.uk

A little ramble through the winter sky - Canis Major the Greater Dog

 Canis Major is a stunning constellation with many bright stars and clusters, unfortunately for observers in Britain it is always low in the sky, so we never see it at its best. It represents one of the two dogs the other being Canis Minor that follows at the heels of Orion the Hunter.

The brightest star in Canis Major, Sirius is also the brightest star in the sky. This is the dog star and sometimes known as the scorching one or the Nile star. Although low down in winter skies it is easy to find. If you do need a guide to find Sirius, you can use the stars of Orion’s belt and draw a line down and to the left this will lead you to Sirius.

At magnitude -1.4 (it has a minus sign in front of the magnitude number because it is so bright, there are 3 stars with minus magnitudes in the night sky) Sirius outshines all the other stars in the sky but appearances can be deceptive because Sirius is very close to us being only 8.6 light years away. It is an A class star which means it is hotter than the Sun with a temperature of 9,500’C compared to 5,800’C of the Sun.

Sirius was very important in ancient Egypt because astronomers/priests would wait to see Sirius rise just before the Sun rose in the morning sky. They knew this meant the river Nile was about to flood, it was at this point that farmers had to make sure their fields were ready for the inrush of water and sediment that would help their crops to grow. This astronomical event is known as the Helical Rising. 

Sirius has a companion star a white dwarf which was discovered by the American telescope maker Alvan Clark in 1862 when he was testing a 15-inch refractor. A white dwarf is a small, faintly lit object made of super dense stuff called degenerate matter. It is thought that most stars, including the Sun, will end their days as white dwarfs. A teaspoon full of white dwarf material would weigh many tons.

As Sirius is the Dog Star it seems appropriate that the small companion star which is officially known as Sirius B should be known unofficially as ‘The Pup’

We know that the brightest stars in a constellation are allocated a letter from the Greek alphabet with the brightest being alpha then beta etc., and we have also seen that the system often does not work, well here we go again.

Most of the star names are Arabic which is why they can sometimes seem strange to us.

The second brightest star is epsilon (5^th letter of the Greek alphabet) or Adhara which means ‘Virgins’ and has a magnitude of 1.5 it is a B class giant star with a whopping surface temperature of 22,500’C which makes our Sun seem very cool by comparison. Adhara is 440 light years away.

A line drawn down from Sirius and slightly to the left leads to delta or Wezen which means ‘Weight’ which has a magnitude of 1.8 and is a F class supergiant and is slightly hotter than the Sun, Wezen lies about 1600 light years away. It is thought that in the next 100,000 years Wezen could destroy itself in a supernova explosion.

To the right of Sirius is beta or Murzim which means ‘Announcer’ and should be the 2^nd brightest star in this constellation however it is in fact the 4^th. Murzim is a magnitude 2.0 blue giant class star lying 500 light years away, it’s another very hot star with a surface temperature of 22,750’C. 

Below Wezen and to the left is eta or Aludra the meaning is unknown and is B class supergiant of magnitude 2.4 , with a temp of 14,750`. Aludra is about 2,000 light years away. It will also become a Supernova in the next few million years.

A line drawn to the right from epsilon will lead to zeta or Phurud meaning the ‘Bright Single Ones’. This is a magnitude 3.0 star, 362 light years away. Another B class star this time a B2 with a temperature of 18,400’ C.

To the left of Sirius is gamma or Muliphein whose meaning is unknown. Gamma is of magnitude 4.1 and is a B class giant with a surface temperature of 13,100’C and lies 440 light years away. There is a mystery here because Gamma appears to have varied over a period of many 100s of years. It is recorded that in 1670 the Italian astronomer Montanari said that it disappeared from view. It was not observed for another 23 years.

Below Sirius is an open cluster, M41 which contains about 80 stars and shines at a magnitude of 4.5 it is about 2,100 light years away it was recorded as far as back as 325 BCE by Aristotle in Greece. In ‘modern time’ it was reported by the Italian astronomer Hodierna in 1654 and recorded by Messier in 1765.

NGC 2362

An open star cluster NGC 2362 was discovered by Hodierna in 1654 this cluster was not reported again until it was eventually found by William Herschel (discoverer of the planet Uranus in 1781) on March 4, 1783

NGC 2362 contains about 60 stars and is of mag 4.1 and is only about 25 million years old.  The brightest star in this cluster is tau which is of magnitude 4.39 and is a class O class supergiant star with a surface temperature of an incredible 31,500’C, it is one of the most luminous supergiant’s known. The cluster is about 5,000 light years in distance from Earth.

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A little ramble through 19th century astronomy - Meteor of June 17th 1873

Academy Saturday 20^th June 1874 

DR. GALLE, of Breslau, has discussed at some length, in the Astronomische Nachrichten, all the available observations of the meteor of June 17, 1873, which passed over the north of Hungary, Austria, and Bohemia. It appears that it was first seen at a height of 100 miles above the earth, and that it disappeared when about twenty-one miles high, after having described a path of 290 miles in about ten seconds, giving a velocity in space of about twenty-eight miles in a second. his velocity is too great for a parabolic orbit, and it would seem, therefore, though there is some uncertainty about the observations of duration, that the meteor, at the time it was seen, was describing an hyperbola. But it is to be remarked that it was then under the influence of the earth’s attraction, and it would be necessary to calculate the effect of this, which Dr. Galle does not appear to have done, before drawing any conclusions as to the orbit described previous to the rencontre. It may very possibly have been peaceably circulating round the sun in an elongated ellipse, as other meteors are in the habit of doing, until it fell in with our planet.

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Cooke Telescope Tales - Jupiter 1860

RAS vol 31 1871 p 75 

Part of a note on the changes in the colour of the equatorial belt of Jupiter by John Brown esq. 

On a fine night in January 1860, I turned Mr Pritchard’s 6.75 inch equatorial by Cooke, for about half an hour on Jupiter. The planet was so well defined, and the details of the markings on the equatorial belt were so peculiar, that I mad a sketch of them, noting at the same time the remarkable brown colour of the equatorial belt. One of the edges of the belt (I think the upper side in the instrument) was beaded or divided into egg shaped masses, which must have been of brighter or lighter colour than the background of the belt, to have given them so much prominence.

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A little ramble through Hydra the Water Snake

Hydra is the largest constellation in the sky but is by no means easy to find on account of its faintness. Hydra winds its way from the head in the northern hemisphere on the borders of Cancer to the tip of its tail south of the celestial equator near Libra and Centaurus.

There is a suggestion that Hydra it is part of the story of Jason and the Argonauts in that it represented the Dragon of Aetes helping to guard the golden fleece. The Hydra would be destroyed by Hercules.

It is possible that the Hydra was the snake depicted on a uranographic stone from the Euphrates dating to about 1200 BCE.

The Arab astronomer Al Sufi thought that the constellation was Al H’ail the Horse and was formed of stars that are now in Hydra but some also from Leo and Sextans

The Egyptians considered it the sky representative of the river Nile and gave it their name for the river.

Hydra has only one bright star Alphard which comes from the Arabic Al Fard al Shuja which means the Solitary One in the Serpent. Another Arabic name for Alphard was Al Fakar al Shuja which means the Backbone of the Serpent.

Tycho the last of the great pre telescopic astronomers called the star Cor Hydrae or the Hydra’s Heart in the 1590s.

Alphard is a magnitude 2.0 star the same brightness as the North Star but because it is not as high as the north Star it does not seem as bright. Alphard is 177 light years and is a K class star making it cooler than the Sun.

There are three Messier objects in Hydra.

Messier 48

An open cluster discovered by Messier in 1771 there is some confusion with M48 because the position given by Messier was not where M48 actually is. In 1783 Caroline Herschel, sister of William Herschel identified it, but the credit still goes to Messier. Sir John Herschel Caroline’s nephew described it “a superb cluster which fills the whole field; stars of 9th and 10th to the 13th magnitude – and none below, but the whole ground of the sky on which it stands is singularly dotted over with infinitely minute points

 M48 is 2,500 light years away shines at mag 5.8 and contains around 450 stars. A ;pair of binoculars will be needed to see it. 

Messier 68

A globular cluster discovered in 1780 , William Herschel described it "a beautiful cluster of stars, extremely rich, and so compressed that most of the stars are blended together". Its magnitude is 9.7 and is 33,000 light years away. A small telescope will be needed to find M68 

Messier 83

The Southern Pinwheel Galaxy so named because it looks like M101 the Pinwheel Galaxy in Ursa Major, it was discovered in 1781, it had been seen earlier by Nicolas Loius de Lacaille in 1752 from the Cape of Good Hope. M83 lies at a distance of 15 million light years. M83 shines with a mag of 7.5. A small telescope will be needed to see it.

Six supernovae have been observed in M83: SN 1923A, SN 1945B, SN 1950B, SN 1957D, SN 1968L and SN 1983N.

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A little ramble through the winter sky - Perseus

Perseus was the hero of Greek mythology who rescued Andromeda who was chained to a rock waiting to be eaten by the Kraken sea monster.  Previously he had killed the medusa.  The Gorgons eye is marked by Algol. Perseus lies in a rich part of the milky way and is worth sweeping with binoculars.

In 1901 a brilliant nova appeared in Perseus it reached magnitude 0.2 between delta and beta.

Near gamma lies the radiant for the Perseid meteor shower which occurs every August.

Alpha  or Algenib which means side  or is sometimes known as Mirfak the elbow. It has a magnitude of 1.8 and is a F class supergiant with a surface temperature of 6,300 degrees and is 510 light years away.

Beta or Algol which means the winking demon is an eclipsing binary star that John Goodricke studied from York in 1782, he realised that there were two stars there eclipsing each other causing the star to change in brightness. The eclipse occurs every 2.8 days and the magnitude varies between 2.2 – 3.5. Goodricke did not discover the variability that was done by the Italian astronomer Montanari in 1669. Algol lies at a distance of 90 light years and has a surface temperature of 13,000’C and is a B class star. The star which is eclipsing Algol cannot be seen with the naked eye.

Zeta has a magnitude of 2.9 and is a B class supergiant with a temperature of 20,500’C and is 750 light years away.

Epsilon also has a magnitude of 2.9 and is a B0. Class star. As hot as zeta is epsilon is even hotter with an incredible temperature of 26,000’C and is 640 light years away. Both zeta and epsilon will probabably end their lives in a massive supernnva explosion.

Rho a semi regular variable varying between magnitude  3.3 and 4.0 in  aperiod or around 50 days. Its a M class red giant with a temperature of 3,800’C and is 308 light years away.

NGC 869 and NGC 884  Mag 3.7 the famous double cluster sometimes also known as chi perseus. These are open clusters with 350 and 300 stars respectively, lying about 7,600 ly away and about 300 light years apart.   NGC 869 and 884 are of magnitude 3.7 and 3.8 respectively, which in binoculars resolves into a grand pair of bright stellar star fields about 0.5 degrees apart. Each cluster contains over 300 blue white super giant stars. They are about 7,500 light years away.  

The letters NGC refer to the New General Catalogue of galaxies and star clusters and was introduced in 1888. Although its name is the New General Catalogue we still use that term today.  

In the 18th century the French astronomer Charles Messier was looking for comets with his small telescope. Although he found around a dozen comets none were very bright. Messier did however come across many fuzzy comet looking objects that  were not comets. He produced this list of noin comet objects whcih today is referred to as the Messier list of non comet objects and is used by astronomers. Its ironic that his comets are forgotten but his list of non comet objects has not been forgotten.                              

 While it was curious that Messier overlooked the double cluster maybe it was too obviously not a comet, he did however discover another open cluster in Perseus, this is M34 glimmering at mag 5.5 just visible to the naked eye to the right of Algol.

M34 is a loose aggregation of about 60 stars, M 34 is about 100 million years old, much older than the double cluster. M34 is only spread across about 10 light years. It is a wonderful sight in binoculars or small telescopes.

It was seen by Messier in 1764 who described it as a faint cluster of stars between the head of medusa and the left foot of Andromeda. The stars may be detected with a simple telescope.

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A little ramble through 19th century astronomy - Rio de Janeiro 1874

 Nature June 11^th 1874

Les Mondes announces the death of Mme. Liais, the wife of the director of the Observatory of Rio de Janeiro, who acted as the secretary of and co worker with her husband in all his labours. She accompanied him in his dangerous expeditions into the centre of Brazil, and died in consequence of the sufferings she endured during her travels with her husband.

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Cooke Telescope Tales - a number of telescopes for London

Edmund Wheeler a lecturer (I don’t know in which subject) of London in 1857 purchased a number of telescopes from Thomas Cooke & Sons. 

In February a 2.75 inch was brought, while in May a 4 inch engraved ‘Edmund Wheeler London’ and finally in September a 4 inch telescope on a plain equatorial stand with brass finder, 4 astronomical eyepieces and a sun prism. The cost of this telescope was £40. 

In 1864 the 4 inch which was not engraved was being sold for £40. This was the same price that the telescope was brought for.

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The Astronomy Show on Drystone Radio

 Join me, Martin Lunn MBE every Monday evening from 7.00 pm-9.00 pm on the award-winning Astronomy Show on Drystone Radio, probably the only regular astronomy show on any radio station in the country. 

I will take my weekly look at the night sky and look at all the latest news in astronomy. There will be the astronomical anniversaries this week plus the latest news from the astronomical societies in the north of England.

The Astronomy Show every Monday evening only on Drystone Radio live online at www.drystoneradio.com DAB radio in Bradford and East Lancashire, or 102 and 103.5 FM and can also be heard later on the Drystone Radio Podcast.

A little ramble through astronomy in Yorkshire - Thornborough Henge

 We now travel back in time not this time in millions but in thousands of years to around 3,500 BCE (Before Christian Era) to discover one of the most important ancient sites in Britain, this is the Thornborough Henges. They are located near the village of Thornborough which is in the Hambleton district of North Yorkshire near to Bedale. The henges consist of a series of three circular mounds with ditches and banks that were probably in use for over a thousand years. This site is often referred to as the ‘Stonehenge of the North’.

Thornborough Henge is the world’s only triple henge with the length of the three circles covering a distance of about one mile.  The henges are aligned northwest to southeast and laid out at approximately 550m apart.  All are of similar size and shape, have a diameter between 240 and 275 metres, and stand some three meters in height. We cannot be sure why it was built some astro archaeologists think that Thornborough may have been a pilgrimage centre where people sought spiritual salvation and that it served an economic and social needs however there does appears to be a definite astronomical connection.

The Thornborough Henges align with one of the most famous star patterns in the sky, Orion’s Belt.  The henges do not form a straight line but instead were intentionally shaped like a ‘dog leg’ to reflect the shape that the stars of Orion’s belt form in the sky. The constellation of Orion is very well known and is one of the two main signposts in the sky which help astronomers to find their way around while learning the positions of the stars in the night sky. The other is the Plough or Big Dipper as the Americans prefer to call it. The Plough is part of the constellation of Ursa Major the Great Bear, and while the Plough is visible all year around while in Britain Orion can only be seen in the winter sky.

Orion is one of 88 constellations recognised today be astronomers today. These are just like giant pictures in the sky and if you can find them it is possible to start reading the stories they are telling us. Of these 48 were designed by the Greeks and therefore by convention we tend to use the Greek myth and legends attached to them. Most other civilisations had their own versions of the ones we use here in the west. The other 40 constellations were added from the sixteenth century onwards by astronomers filling in the gaps between the main star groups in the northern hemisphere. When European explorers travelled into the southern hemisphere, they saw stars that cannot be seen in Europe so created a series of constellation in the southern sky. Many of these are depictions of what were at the time newly invented scientific instruments. This explains why in the southern hemisphere we see constellations such as Telescopium the Telescope and Microscopium the Microscope. The vast majority of these modern constellations both in the northern and southern hemispheres are comprised of faint and obscure stars. 

Orion on the other hand is a magnificent constellation easily recognised by four bright stars that form a large rectangle in the sky inside which are the three stars that form Orion’s Belt. The top left-hand star of the rectangle is the famous red star Betelgeux which is often called Beetlejuice!  As we look at the belt stars from left to right they are Alnitak, Alnilam and Mintaka.  The stars names may seem a little different to us this is because they are Arabic. When we translate the stars of Orion’s belt into English, we discover that Alnitak means The Girdle, Alnilam the String of Pearls and Mintaka is the Belt.

This same astronomical alignment can be found in the great pyramids in Egypt, but the Thonrborough Henges are about 1,000 years earlier than the Egyptian pyramids. This could be the first known monument to align with the constellation of Orion. Was this co- incidence that the people of Yorkshire and those in Egypt created the same pattern on the ground or maybe people travelled around the world thousands of years ago exchanging thoughts, ideas and customs? 

The structures of the henges were aligned so its western end pointed towards the mid-winter setting of Orion which also meant that the eastern end aligned towards the midsummer solstice.

Today we talk about light pollution and how difficult it is for people who live in cities to see the stars properly.  We can be certain that the night skies were much darker when the henges were constructed over 5,000 years ago, there would be no light pollution at all. Today Orion is still an amazingly wonderful constellation to look at but with darker skies it must have looked even more impressive, and this perhaps is one of the reasons why they had such a fascination for this one particular group of stars.

Today, all three of the Thornborough Henges, as well as the land connecting them together, are listed as Scheduled Ancient Monuments.

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Cooke Telescope Tales - comet seen from Gibraltar in 1860

 Colonel De Rottenburg wrote in a letter dated June 24^th, 1860, from Gibraltar. “I observed a brilliant comet in the constellation of Auriga this evening, a line from beta through a Geminorum continued about three times their distance passed through its nucleus. 

It was easily seen with the naked eye; the nucleus was a little less brilliant than Castor. Its altitude above the western horizon about equal to that of Venus at the same time. 

I turned my 6 feet equatorial of 4.5 inches aperture made by Messrs Thomas Cooke & Sons of York on the comet. 

It has a bifid tail, very like that of the year 1846 as shown in Keith Johnsone’s Atlas of Astronomy which is edited by Mr Hind. I used powers of 26, 50 and 100 on the comet; the nucleus has a very sensible disk. It bore the powers of 100 very well; one portion of the tail is much longer than the other, the south preceding being the longer. 

With 100 power the nucleus was situated within the nebulosity, and the nebulosity was more arched and prominent on the south preceding part. It was first seen by a gentleman here on Saturday evening 23^rd June.

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