Alpha Centauri one of the leading double stars in the southern hemisphere was observed by G D Hirst using his 4.25 inch Cooke telescope and James Nangle using his 6.25 inch Cooke telescope in Australia in June and July 1906.
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On the night of May 20th, 1863, Mr N R Pogson, the government astronomer at Madras, observed a star of the ninth magnitude on a spot in the constellation Scorpio, where no star had been seen in the months of April and May during the last nine years.
At first it was supposed to be one of the minor planets, but
a series of micrometrical measures of its position with respect to other stars
near it, made the same night, established its fixity, and revealed its true
character.
On the following night it was decidedly less bright, and by
the 28th May it had diminished to less than the twelfth magnitude.
Strong moonlight then interfered with observations, but on the night of June 1st,
during the darkness caused by the total eclipse of the Moon, it was again
looked for but was no longer visible.
Only three other stars are known, discovered respectively by
Mr Hind, Mr Baxendell and Herr Auwers, whose appearances and disappearances
take placed so suddenly; and every addition to the list of objects so
remarkable is regarded with considerable interest by astronomers.
Mr Pogson called his new variable star U Scorpio.
Today we know that U Scorpio is a recurrent nova system that
has been seen to brighten up not only in 1863, but also 1906, 1936, 1979, 1987,
1999, 2010, and 2022. Pogson’s observations from 1863 are the only ones known regarding that outburst.
None of the outbursts were bright enough to be seen by the
naked eye, all needing either binoculars or a small telescope.
www.theramblingastronomer.co.uk
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.
On November 5th / 6th 1907 Mr A B Cobham and Mr G D Hirst using a 4.5 inch Thomas Cooke & Son telescope in Australia saw a dark spot on Saturn. This was afterwards ascertained to be Titan.
They also both commented that they caught glimpse of the
edge of the ring at flashes, the impression indicating the extreme fineness and
delicacy of the rings when seen edgewise.
www.theramblingastronomer.co.uk
In the south quite low down in the sky in the south in late summer and early autumn is one of the constellations that form the zodiac. This is Capricornus the Sea Goat. Although there are no particularly bright stars in Capricorn it has some of the oldest mythological legends attached to it.
Normally associated with a sea goat by Aratus 315 – 240 BCE
the Greek poet who drew the pictures we recognise as the 48 classical
constellations it was a Horned Goat, while Eratosthenes 276 – 194 BCE he was
the Greek astronomer and mathematician who measured the circumference of the
Earth thought that Capricorn was half fish who jumped into the river Nile to
escape the monster the Typhon.
In Persia, it was Bushgali, in Syria it was Gadjo, in Turkey
it was Ughlak while to the Arabian astronomers it was Al Jady, all these names
refer to a goat. In Egypt it was Chnum or the God of the Waters, this would I
assume be associated with the rising of the river Nile.
In Asia Capricorn was sometimes known as The Southern Gate
of the Sun, this would almost certainly be because Capricorn is the
constellation where the Sun is at its lowest in the sky, and this is when the
winter solstice occurs. The Tropic of Capricorn is the position at
approximately south 23 degrees where around December 21st the Sun
will be directly overhead. Although it is still referred to as the Tropic of
Capricorn the position has moved and is now moved into the neighbouring
constellation of Sagittarius. This is due to a very long-term effect called
Precision or the wobbling of the Earth.
The second mythical
king of Rome Numa Pompilius c715 BCE – 673 BCE began the year when the Sun was
in the middle of Capricorn and when the day lengthened after the winter
solstice.
Today we see Capricorn as the sea goat, but some Greek and
Arabic astronomers saw it as just goat like.
Early Hindu names were Mriga and Makara, while the Tamils
saw it as Makaram an antelope. It was sometimes shown with the head of a goat
upon the body of a hippopotamus indicating some kind of amphibious creature.
In China it was the zodiacal bull or Ox that would later
become Mo Ki the Goat Fish. Sometimes the Chinese grouped some of the stars of
Capricorn and Sagittarius together to form Sing Ki the Starry Record. Very
early in astronomy in China it was known as the Dark Warrior.
The brightest star in Capricorn is not alpha but delta. I have mentioned before that in 1603 the German astronomer Johann Bayer introduced a system on his Uranometria star atlas using the 24 letters from the Greek alphabet. Whereby the brightest star is labelled alpha followed by beta then gamma and all the way down to omega which is the 24th and last letter of the Greek alphabet. It does not always follow that this system works. It doesn’t in Capricorn. I don’t know why this situation sometimes occurs.
Delta or Deneb Algedi which is Arabic and means The Tail of
the Goat, it has a magnitude of 2.9 and is 39 light years away. It is an
eclipsing binary system of the Algol type. The prototype for this class of
variable star was discovered in 1669 by the Italian astronomer Montanarri and
explained by John Goodricke the deaf astronomer and Edward Pigott in York in
1782. I called these two astronomers the Fathers of Variable Star Astronomy
because of the work they did together between 1781 -1786 observing and explaining
the changing light of some of the stars they observed. This partnership went on
until the untimely death of John Goodricke at the age of just 22. The magnitude
of delta varies between 2.8 -3.0 over a period of just over one day.
It was close to delta that the planet we now call Neptune as
discovered in 1846 through the calculations of the astronomers Urbain Le
Verrier in France and John Couch Adams in Great Britain. Neptune was discovered at the Berlin
Observatory.
The next brightest star in beta or Dabih the meaning of
which is uncertain it’s another double star. The brighter component has a
magnitude of 3.1 and its companion star has a magnitude of 6.1, the pair can be
seen with binoculars. The system is 340 light years away.
Alpha or Al Sa’d al Dhabih, the Lucky one of the
Slaughterers this name appears to refer to the sacrifice of animals by the
Arabs at the time of the heliacal rising of Capricorn. Another double star, the
two components can be seen with the naked eye under the very best of
conditions. The brighter star has a magnitude of 3.1 the other star has a
magnitude of 4.3. The system lies at 690 light years away.
The last star I will mention here is gamma or Nashira which
means the fortunate one or the bringer of good tidings. It has magnitude of
3.7, it’s an A class star meaning it’s hotter than our Sun and is 139 light
years away.
There is one messier object in Capricorn this is Messier 30,
it is known as the jellyfish cluster. It’s a globular cluster and was
discovered by Charles Messier in 1764 who described it as a circular nebula
without a star. Globular clusters are
old clusters of stars compared to open clusters which are formed of young
stars. M30 lies close to a 5th magnitude star labelled as 41
Capricorn. This was the 41st star catalogued by John Flamsteed in
Capricorn as part of his survey of the stars in the night sky. He was the first astronomer royal in the late
17th century. His project was
to record the bright stars in all the constellations visible from London.
Today astronomers
refer to M30 as a remarkably bright, large and a slightly oval cluster. It lies
at around 27,100 light years and is about 93 light years across, this gives
some idea of just how big some of these globular clusters can be. M30 is
believed to be about 12.9 billion years old. With a magnitude of 7.2 it can
just be glimpsed as a spot of light through a pair of binoculars.
www.theramblingastronomer.co.uk
W M Baxter used a 5 inch Cooke equatorial in Edinburgh to observe a series of occultations of stars during the partial eclipse of the Moon on the night of 16th-17th December 1899. He observed 10 stars before fog and cloud prevented further observations.
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York Herald Thursday 22nd March 1877
Strange news has been recently received from an Australian
observatory (Adelaide). It might be described as revolutionising our ideas
respecting the largest of the planets, were it not that the careful study of
much older observations had already led the more advanced students of astronomy
to adopt the theory which has now been demonstrated by direct observation.
It has been shown that all the phenomena presented by the two gas giants planets correspond with this theory, whereas not one in ten can be explained by the older theory.
Fortunately in the case of Jupiter, we have evidence we have evidence from the Adelaide Observatory where a fine (8 inch) telescope by T Cooke & Sons of York has been erected, and where a singular purity of air greatly assists astronomical observation, two practised observers (Mr Todd and Mr Ringwood) on two different occasions, both observing on each occasion saw the nearest of Jupiter’s satellites through the outer layer of the planet’s cloud laden atmosphere, which must, therefore, of necessity, be at least 2,000 miles in depth.
In his book ‘Flowers in the Sky’ Richard Proctor makes
references to this observation by Mr Todd and Mr Ringwood.
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Sir, I beg to call attention of your readers to Herschel’s planetary nebula No.37 in Draco, situated between Zeta and Delta of the that constellation, and close to the pole of the Ecliptic.
I was looking at the nebula a few nights ago with my
reflector of 12-inch aperture, having silvered glass specula, and perceived
very near to its centre and deeply immersed in the pale blue nebulosity, a
small star of the tenth magnitude or thereabouts.
On referring to Admiral Smyth’s ‘Cycle’ I have found he
describes the nebula as a “bright pale blue object” but makes no reference to
any star. I have not the means of knowing in what manner it was described by
Sr. W Herschel, its discoverer; but it would be singular if the star was then
as visible as it is now, but he should have missed it. I see it best with a
power of 110, and the largest possible aperture.
I hope this may meet an eye of some of your numerous
readers, who may possess instruments of great calibre so as to verify my
observation and detect any peculiarity in the object which my instrument will
not reveal, and not hitherto observed.
Frederick Bird
Key Hill, Hockley, Birmingham
July 16th 1863
This object is NGC 6543 the Cat’s Eye Nebula a planetary
nebula which does have an 11th magnitude central star inside a
bright luminous ring that is surrounded by a diffuse shell of pale light.
NGC 6543 was the first object of its kind to be analysed
with a spectroscope by William Huggins at Tulse Hill Observatory in London on
August 29th 1864.
NGC is the New General Catalogue of nebula and clusters that
was introduced in 1888.
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Mr V Cerulli reports his observations made at Teramo, in the Bulletin of the Belgian Astronomical Society, and accompanies his account with a chart and 11 drawings made December 1896 and January 7, 1897, with a 15½-in. Cooke refractor.
He remarks that the canals appeared hardly thinner on a disk
of 7 " (July 1896), than they were on the disk of 17" (December) and,
therefore, supposes that the lines become thicker as Mars travels away. He also
found that lines that appeared dark and distinct when near the limb became
fainter and narrower when on the meridian.
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In modern mythology Canis Minor is the Lesser Dog constellation that together with Canis Major follows Orion the Hunter across the sky.
It appears not to have been known to the classical Greek
astronomers it was simply referred to as rising before his companion star. It
is about the time of Ptolemy c100-170 CE that it appears as a separate
constellation and is therefore included in the 48 classical constellations.
There does appear to be suggestions that the stars that we
refer to as Procyon and Gomeisa in Canis Minor were known to the ancient
Mesopotamians as the ‘Twins’ this term dates to around 1100BCE. The Arab
astronomers of a thousand years ago called the constellation Al Kalb al
Makbudah or the Lesser Dog.
As the constellation is close to Orion it is seen in the
winter skies, however as it follows Orion and is higher in the sky than Canis
Major it can be seen later in the year into early spring. It’s a small
constellation and although it contains Procyon a bright star the rest of the
constellation has few bright stars and no clusters or galaxies worth
mentioning.
The brightest star is alpha or Procyon or the Small Dog Star. The last of the great Arab astronomers Ulug Beg called the star Al Shamiyyah which together with other sources suggest the name of the Northern Sirius. The Euphratean astronomers called it Palura of the Cylinders, or the Star of the crossing of the Water. This name is given with reference to the River of Heaven or the Milky Way which is very close to Canis Minor. The Chinese call it Nan Ho or the Southern River.
Procyon with a magnitude of 0.3 forms part of what is called
the winter triangle with the stars Sirius in Canis Major and Betelgeuse in
Orion. Inside this triangle the milky way flows. Procyon is a binary system
with the main star being an F class star hotter than the Sun with a small white
dwarf companion which was discovered in 1896. This white dwarf is like the
white dwarf companion of Sirius, its small and the material that makes it is
very dense in nature. Another feature it has with Sirius is that it is
relatively close to us, it is only 11.5 light years.
The only other bright star is beta or Gomeisa , there does
not appear to be any ancient names attached to the star. The Arab astronomers
called it either Al Gamus or Al Murzim which is the same name as Beta Canis
Major in both cases the name refers to the whole constellation. Its magnitude
in 2.9 and is 160 light years away, and is a B class star hotter than our Sun.
Although the milky way flows through Canis Minor there are
no bright star clusters or galaxies, the ones that are here are all very faint
and require reasonable size telescopes to see them and are therefore beyond the
scope of our little ramble through Canis Minor.
www.theramblingastronomer.co.uk
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.
In 1896 the Rev J H Jenkinson of St Mary’s vicarage Reading, Berks described a series of sunspot drawings he had made between February and August of that year. He used a 4.5 inch Thomas Cooke of York telescope.
www.theramblingastronomer.co.uk
The following circular has been issued by the Imperial Academy of Sciences at Vienna: -
For several years past there have been remarkably few
discoveries of comets. The cause of this fact, which seems inconsistent with
that of the wider distribution of telescopes suitable for such discoveries, may
be due to the special attention that has been given t the small planets. It is,
however, much to be regretted that there has been such a slight increase in our
knowledge of the comets, in view of the recently established connection between
shooting stars and comets. It is exceedingly desirable that we should know more
than two or three hundred out of the many thousands of comets which undoubtedly
belong to our system, especially as most of those which we know move in
parabolic orbits. Were our knowledge of comets more complete we should surely
know more meteor streams and comets belonging one to the other. Mindful of Herr
Schumacher’s words “It is natural that astronomers intrusted with the
administration of a well-furnished observatory should have no time left for
sweeping the sky so minutely and so perseveringly as is necessary for discovering faint bodies,
whilst on the contrary , it seems certain that to the many amateur astronomers
who have less extensive means of observation hardly any more useful kind of
activity could be recommended”, The Imperial Academy of Sciences at Vienna is
induced tom propose for the discovery of comets during the three years from May
31st 1869 to May 31st 1872 eight prizes annually .
consisting as the receiver may choose of a gold medal or of twenty Austrian
ducats representing its value in money.
The award of these prizes will be subject to the following
regulations: -
1. The
prize will be given only for the first eight comets discovered in each of the
three years named, and only for such comets as are telescopic at the time of
discovery, that is invisible to the naked eye. The comet must not have been
seen before by another astronomer and must be one whose appearance could ot be
predicted with certainty.
2. The
discovery must be communicated immediately and without waiting for further
observations, to the Imperial Academy of Sciences, by telegraph if practicable,
and otherwise by the earliest post. The Academy undertakes to transmit the news
immediately to other observatories.
3. The
time and place of discover with the plan and course of the comet must be given
as exactly as possible with the first notice. This first notice is to be
supplemented by such later observations as may be made.
4. If
the discovery should be confirmed by other observers, the prize will not be
awarded unless the observations of the discoverer suffice for the determination
of the orbit.
5. The
prizes will be awarded in the general meeting of the Academy held at the end of
May each year. In case the first notice of a discovery arrives between 1st
January and the end of May, the final award of the prize will be deferred till
the general meeting in May in the following year.
6. Application
for the prize must be made to the Academy within five months from the time of
the arrival of the first notice. Later applications will be considered.
7. The
Imperial Academy will procure the decision of the permanent astronomers of the
Observatory at Vienna as to the fulfilment of the conditions in Nos 1,3, and 4
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The Full Moon on June 11th is called the Strawberry Moon, because this is the time of year when the strawberries, considered the most celebrated and important of the berries, were traditionally harvested. Nowadays we can buy strawberries at any time of year.
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I am glad to be able to report that observing conditions generally have been very good with us since the beginning of last month, and that at least one other member besides myself has taken advantage of the good seeing to make drawings of Jupiter. I am unfortunately divorced from my observatory for some months, but have with me in the country an excellent 5-in. Cooke altazimuth as well as accurate time.
I have never hitherto prosecuted a careful and continuous
study of the giant planet's surface, and confess to great surprise at the vast
and rapid changes that become apparent. This especially struck me first in the
case of the N. equatorial belt, the northern and equatorial components of which
exhibited alternately dark masses and condensations, divided by white spots
after intervals of only five Jovian rotations. On March 13 and 14 there were
typical instances of this.
On March 26, 20h 40m, G.M.T., a faint wisp across the
equator, was conspicuous, and next night, March 28, 2h 20m G.M.T., was
invisible, while the equatorial region near the c.m. showed considerable
change. Definition excellent, 4 to 5 on both occasions, power 200. The N.
temperate area, however, has puzzled me most, for the three belts often seen
have varied much both in visibility and latitude, while with exquisite
definition on April 1, at 0h 20m G.M.T., the following portion seemed overlaid
with vapour of a sage green tint, and the belts (2) were only faintly visible
in their preceding parts,
The Red Spot has been well seen on several occasions of
almond shape, the f. end slightly more pointed than the p. Its tint seemed
uniform, and a very delicate brick red, like a faint stain. It is overlaid on
the S. side by the S. temperate belt, which is closely double through nearly
its whole extent, and f. from the centre of the Red Spot is much darkened and
sinuous. The great spot's preceding end was estimated on c.m. at 1h 15m G.M.T.,
April 1, and the following end on c.m. at 21h 52m 36s G.M.T. of same date. In
the transit of Satellite I. on February 22, observed at Waverley, near Sydney,
with my equatorial, the shadow must have been occulted by the satellite, which
is perhaps worthy of note.
WALTE R F. GALE .
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Canis Major is a stunning constellation which I am afraid to
say we never see at its best from Britain because it is quite low down in the
sky. In the Mediterranean area it would be much higher in the sky and would
look even more impressive. The constellation which can be seen in the winter
months in Britain represents one of the hunting dogs that follow Orion the
Hunter across the sky and contains Sirius or the Dog Star the brightest star in
the sky.
In classical Greek mythology the constellation was simple
known as Canis which represented Laelaps who was a gift from Zeus and was the
hound of Acteon who was the son of the priestly herdsman Aristeaus and Autonoe
in Boeotia which is part of Greece. From the earliest of times, it has always
been the Dog of Orion an image of which Aratos drew in his phainomena.
The Arab astronomers knew Canis Major as Al Kalb al Akbar
the Greater Dog, the Arabic astronomer Al Biruni also referred to it as Al Kalb
al Jabbar the Dog of the Giant. The Hindu astronomers called it the Deer
Slayer, while northern European civilisations called it Greip the Dog of the
myth of Sigurd.
As I have already said Sirius the Dog Star which is the
brightest star in the sky has at least 50 different names given to it be
civilisations around the world, Sirius is sometimes written as Syrius, this
version was used as late as the time of Sir John Flamsteed the first astronomer
royal in the early 1700s and has often been associated with sparkling or
scorching .
Although most ancient civilisations have the constellation
connected with a dog to the native aboriginals of Australia it was their Eagle.
As Sirius is the brightest star in the sky the Egyptians sometimes associated
it with Thoth the god of writing, wisdom and magic. Sirius was also worshipped
by the Graeco - Egyptian name of Sothi the Brightly Radiating One and Sothis
Fair Star of the Water.
The Phoenicians are said to have known the star Hannabeah,
the Barker, Arabic astronomers sometimes called it Suhail which is a general
designation for bright stars. However, some Arabic sources give it the name
Barakish meaning of a Thousand Colours. This would be due to Sirius being seen
low in the sky and light passing through the atmosphere making the star to
appear to twinkle a lot, hence appearing to change colours. In China the astronomers don’t seem to have
made so much of Sirius as other people did. It is sometimes mentioned with
other stars in Canis Major as Lang Hoo.
Sirius has an association with Egypt in the event known as
the Heliacal Rising. This is when Sirius appears in the sky just before sunrise
in the morning. Egyptians knew that when this happened the river Nile was about
to flood. Farmers had to make sure their fields were ready to be flooded and
all the important sediments that would be laid down by the river on the fields
hopefully insuring a good crop for the year.
Associated with the Heliacal Rising is a term that will be
familiar to everyone, and this is the Dog Days of Summer. We can go back
thousands of years to record when the helical rising occurred and was observed,
and these dog days can occur between Jul 3rd and August 10th
depending on when Sirius was first seen.
The brightness of Sirius or its magnitude is -1.4, in astronomy the lower the number the brighter the star. I know this seems strange but that is the way the brightness of stars is worked out. Stars like Sirius which have minus numbers are the very brightest. The brightness of Sirius is because it is astronomically speaking very close to us being only 8.4 light years away. Sirius is an A class star it is hotter than the Sun.
Sirius is a double
star its companion is a white dwarf star. In fact, the white dwarf orbiting
Sirius was the first star of its kind to be discovered. It was purely by chance
when the American telescope maker Alvan Clark was testing a new telescope on
January 31st, 1862, that the companion was discovered. At first it
was not realised how important a discovery it would be, leading to a whole new
area of astronomical research into white dwarf stars. A telescope is needed to see the companion
star.
As Sirius is the Dog Star and the brighter of the two stars
it is known as Sirius A the companion is known officially as Sirius B. However,
because Sirius is the dog star the companion is known unofficially as the Pup.
White dwarfs are very old stars that have lived out most of
their lives. Our Sun will end up as white dwarf star in a few billion years’
time. White dwarfs are stars that have all the gas inside them massively
compressed. This material is known as degenerate material. A tablespoon of
material would weigh many tons.
The second brightest star in Canis Major is not beta but the
star epsilon which is the 5th letter of the Greek alphabet. I have
mentioned before that in 1603 the German astronomer Johann Bayer introduced a
system whereby the 24 brightest stars in a constellation were
allocated a letter from the Greek alphabet, alpha being the brightest, then
followed by beta through to the last letter of the Greek alphabet omega. Here
we have another example where the system does not work. Epsilon whose name is
Adhara which means Virgins.
Adhara has a magnitude of 1.5 it’s a B class giant star with
a massive surface temperature of around 22,500 degrees compared to our Sun’s
temperature of 5,800 degrees. It lies at about 400 light years and will
probably end its life in a supernova explosion and destroy itself.
Next in brightness is delta or Wezen which is the modern-day version of Al Wazn which means Weight. Remember most of the star names we use today are Arabic. Wezen is an F class supergiant star with a magnitude of 1.8 and is about 1,600 light years away, it is hotter than the Sun.
Beta or Mirzam which means the Announcer is to the right of
Sirius, the star marks the right fore foot of the dog. The Chinese call it Juen
She or the Soldier’s Market. It is a magnitude 1.9 star making it the third
brightest star in Canis Major. It lies around 490 light years away and is a B
class giant star with a surface temperature of around 24,500 degrees, yet
another supernova candidate for the future.
Below Wezen and to the left is eta whose name is Aludra; the
meaning of the name is unknown. Its magnitude in 2.4 and it’s a B class
supergiant with a hot surface temperature of 15,500 degrees and is about 2,000
light years away. This is probably yet another candidate for a supernova in the
future.
A line drawn from epsilon or Adhara will lead to zeta or to
give it its Arabic name Al Furud which means The Bright Single One. As the star
has a magnitude of 3.0 its clearly not the brightest star in Canis Major so its
name night seems a little surprising. The Arabic astronomer Al Sufi whose name
will be known by some due to his star catalogue called the star Al Agribah
which means the Ravens. Whichever name we use zeta is 362 light years away and
is another hot B class star with a surface temperature of about 18,000 degrees.
Canis Major contains several star clusters yet surprisingly
only one messier object. This is Messier 41. It was first seen by the Italian
astronomer Giovanni Battista Hodierna 1597-1660 in 1654, although there are
reports that suggest it might have been seen by Aristotle around 325 BCE. This
is quite possible because under good clear conditions it can be seen with the
naked eye as M41 has a magnitude of 4.5.
M41 is an open cluster which contains about 100 stars and is
sometimes referred to as the Little Beehive Cluster. The cluster is around
2,300 light years away and as it is an open cluster it is relatively young
being only about 190 million years old.
Some of the other star clusters in Canis Major include NGC
2360 an open cluster which is known as Caroline’s Cluster after its discoverer
Caroline Herschel, Caroline discovered the cluster in 1783. She was the sister
of William Herschel who discovered the planet Uranus in 1781. With a magnitude
of 7.2 a good pair of binoculars or a small telescope is needed to see it. NGC
2360 is about 3,700 light years from Earth.
Close to NGC 2360 is NGC 2359 known as the Thor’s Hemet
Cluster. It is 11,960 light years away and with a magnitude of 10 a telescope
is needed to see it. At the centre of the cluster is a Wolf Rayer star, this is
an extremely hot star which astronomers believe is going through a period of
its evolution before it goes supernova.
NGC 2362 another open cluster first seen by the Italian
astronomer Giovanni Hodierna in 1654 has a magnitude 6.0 meaning a pair of
binoculars are needed to find it. William Herschel described it as a beautiful
cluster.
I will finish my tour of Canis Major with NGC 2207 which is
a galaxy about 81 million light years away. It is a spiral galaxy and is in the
process of crashing into another galaxy known as IC2163. The IC or Index
Catalogue was introduced in 1895 as a supplement to the NGC or New General
Catalogue that was introduced in 1888.
NGC 2207 is a good hunting ground for supernova hunters in
NGC 2207 there have been 5 supernovae seen in recent years, these being in
1975,1999, 2003, 2013 and 2019.
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The Partial Lunar Eclipse of May 11-12, 1892. By G. J. NEWBEGIN, F.R.A.S.
The night of May 11-12 turned out so exceptionally clear and fine that (though in 16 ° of Declination) the moon soon became a steady object in the telescope. With regard to the eclipse I decided to take a series of photographs at about half-hour intervals, and to endeavour to secure a permanent record of its several stages. The exposures were made at 9.20, 9.50, 10.30, 11, 11.30 p.m., 12 o'clock midnight, and 12.30 a.m. The periods of exposure were varied, to allow for the decreasing illumination of the moon, viz. :— 20s 20s 30s 40s 30s 20s 20s respectively.
The plates were the Ilford ordinary, developed by
hydroquinone. The instrument by which they were taken is a 9-inch Cooke
equatorial, aperture reduced to 2-inch for the whole series. The intervals
between the exposures were occupied in developing the plates.
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We learn from the Melbourne Argus of 23rd February 1863 that the new observatory, for which a grant of £4,500 was recently voted by the Colonial Legislature, is nearly completed, and the colonists are proud of it, as they may be.
The Transit instrument will be second only to those at
Greenwich and Capetown; and Airy’s zenith sector is at present in constant use
in connection with the survey of the colony, and the determination of the
boundary between Victoria and South Australia.
It has been determined to provide this observatory with a
telescope of much greater optical power than any previously used in the
southern hemisphere, to be employed chiefly in observations of nebulae; and the
advice of the Royal Society was desired as to the best instrument to be used.
We believe that it has been decided that a reflector as
large as and similar to Lord Rosse’s to be constructed in this country, should
be employed. Should this of course, which really seems a rather hazardous one
be adopted, we trust that the effects of a long voyage, and extremes of
temperature, and loss of figure and polish, may all be avoided, and that the
colony may reap all the laurels it deserves.
The telescope would be the Great Melbourne Reflector which
was built by the Grub Telescope Company in Ireland then shipped in sections to
Australia where it was installed in the Melbourne observatory in 1869 .
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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.
Civil and Military Gazette (Lahore) Saturday 3rd
January 1891
For sale Owner leaving India
An equatorial telescope of 6 inches aperture by T Cooke & Sons, York driven by clockwork, with stellar and solar eyepieces.
Also the revolving roof or dome (16 feet diameter) of sheet zinc on teak framing, covering the telescope.
H B Hederstedt, late Chief Engineer of the Oude and
Rohilkund Railway, Lucknow
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For the year 1908, a fine set of drawings had been sent by Mr Barnett of Rosario, Argentina made with his 4 inch Cooke & Sons telescope of the Sun. A close examination of the Stoneyhurst drawings shows an almost exact agreement in the sun spot groups delineated.
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