Welcome to the WDAS monthly newsletter for January 2017: a digest of the month's latest contributions to our website. Below you'll find Society News, Sky Notes and In-Focus articles printed in full. There's also future events, and trailers for other articles which appear in full on the website - just a click away!
On the website you'll also be able to comment on articles, and if you'd like to play an editorial role in creating new content, just let us know!
Society News
Our Christmas meal at the Hare and Hounds once again proved a great success. Even though only seven members made it to the banqueting table on the date chosen (and no we didn’t lose any on the way up) did not detract from the evening.
The food was really excellent, as good as we could remember for such an occasion, the toffee cheesecake was to die for. The only slight let down was the standard of cracker jokes and toys – they do seem to get worse each year wherever you go.
I must mention the weather. We have experienced all types over the years, snow and ice, wind, fog, torrential rain. This year felt more like club Tropicana – 13 degrees at 22:30pm, just like the spicy carrot soup...phew what a scorcher. Here’s to next year’s bash... can’t wait!
We are starting to distribute Night Scenes 2017, so if you would like a copy it’s just £4 to society members, £5.50 otherwise. Cannot be certain how many copies will remain once all those spoken for have been dispatched, so don’t delay, it would make a fantastic new year's gift.
In our Solar System we find to kinds of planets: small rocky planets closer to the sun, and ice giants further out. The rocky planets (Mercury, Venus, Earth and Mars) have only three moons among them, whereas the ice giants (Jupiter, Saturn, Uranus and Saturn) have around ninety.
For the reason, we need to look back to the formation of the Solar System, from a giant, swirling cloud which collapsed under its own gravitational mass. As the cloud contracted, it heated-up and started to rotate faster, resulting in a proto-planetary disk hot, gas and dust rotating around a mass at its centre. The central mass, of course, became the sun; but the rest didn't immediately have the circumstances for gravity to pull together. It needed some seed.
Near the sun, the temperature was so high that all the material was gas and couldn't form planets. A little further out there were metal flakes and fragments, and small pieces of rock; which stuck together when they collided, eventually becoming big enough to gravitationally attract matter to them, at which point we call them 'planetesimals'. They grew quickly up to the point when collisions started to break them apart. Only the largest objects survived to become the inner planets.
Outside the orbit of Mars, the temperature was low enough for ice to form in addition to the flakes and fragments. This meant more and better seeds which helped them to grow even faster. After a certain size they were able to hold on to hydrogen and helium which was abundant in the proto-planetary disk; so much so that each became something like a tiny solar system in its own right. That's how the majority of moons formed around the ice giants.
Between Mars and Jupiter is the asteroid belt, containing many planetesimals which failed to coalesce into planets or journey into the inner solar system because of the disruptive gravitational effects of massive Jupiter. Although it's thought that the two moons of Mars (Phobos and Deimos) are two such planetesimals which have been captured into orbit.
So then what of our own Moon? This is thought to have started out as a large planetesimal around the size of Mars, which smacked into the earth in the early solar system. The collision would have ejected so much material into earth's orbit that it eventually coalesced into a ring, and then into the Moon.
So in the end, we probably have just one Moon because there wasn't enough material in the inner solar system to create any more than just one, and because Jupiter tends to stop other potential moons entering the inner solar system.
The video and material for this article was made by UK Astrophysicist Sebastian
Pines, creator of the 'Astronomic' YouTube channel. You can support Seb's work creating videos that help to teach the world about astronomy by sponsoring a dollar or two per month via his Patreon page.
It was just as well there were plenty of savvy IT experts in the auditorium; Prof Southwood’s presentation would not open on his laptop. But after exhausting the logical possibilities, the sound techician logged-out and logged-in again, waited a near-eternity to catch the speaker's attention from an improptu time-filler talk he'd embarked-upon, we were ready to proceed.
As far back as 1982, Prof Southwood recalled, he was present at the meeting at which the Cassini mission to Saturn stemmed. David remembers the date well – June 30th –his birthday. David was founder of what became the Space and Atmospheric Physics group, part of the team arguing for a ‘bolt on lander’ which eventually would be funded by ESA as NASA was reluctant to do so.
The lander was not destined for Saturn, but its mysterious and largest moon Titan. Huygens was born. Prof Southwood was also leader of the team which developed the magnetometer on the main Cassini spacecraft.
In 1996 Cassini was finally launched, the largest planetary probe to be sent into space.
In May 2001 David became Director of Science at ESA, and under his directorship oversaw 3 low cost ESA planetary missions; Smart 1 and Mars Express in 2003 and Venus express in 2004. The same year, in June, Cassini finally reached Saturn. 2004 also saw the launch of ESA’s ambitious Rosetta mission to comet 67P. It was a busy time for David.
Back at Saturn, Cassini had to undergo a very risky manoeuvre in order to enter the correct orbit – a ring plane crossing – twice! David recalled how the tense the control room was at the time, the date, June 30th. On Christmas day 2004, Huygens was jettisoned from Cassini, taking 3 weeks to reach Titan, no communications were possible during this period before it arrived on Jan 14th. It then survived the 2 hrs 27minute descent through Titans hazy atmosphere, landing on the frozen surface.
Titan is Saturn’s largest moon and second largest in the solar system and has a substantial atmosphere, the pressure being 50% more than Earth’s composed chiefly of nitrogen, hydrogen, carbon and methane, but not much H20. On Titan itself methane exists at the triple point, similar to how water exists on earth, taking the form of a gas, solid or a liquid. Huygens had to be designed for any eventuality on landing. Oxygen is frozen out on titan, not leached out like on earth 1 billion yrs after its formation. Titan is therefore similar to a primordial earth, so the opportunity to study such a world, conducting real science, even for a short period, was too good to miss for the small increase in weight of the Cassini mission. The mission wasn’t flawless, one of the cameras malfunctioned, but Huygens did transmit for 72 minutes before contact was lost, data which is still being analysed today.
It turns out Huygens landed on a methane shoreline, it remains the most distant standing artefact built by humans- something Prof Southwood is very proud of.
In 2008, Southwood became ESA’s first Director of Science and Robotic Exploration, before retiring from ESA in 2011 becoming president of the Royal Astronomical Society 2012-2014.
Rosetta finally reached the wonderfully shaped comet 67P in Aug 2014, David joked if they had known the actual shape of the small comet before launch, and they would not have contemplated setting down a Lander on its surface. As it was they were there, so why not have a bash. As we know in November of 2014 Philae made it...just, touching down 3 times before coming to rest, lodged in a crevice, the first manmade artefact to land on a comet. It was another proud moment in David’s life.
David then showed several images of various dignitaries, including the French president, meeting and greeting various ESA scientists involved in the Rosetta and Philae mission. Yes, it was big news in the UK, it was even bigger news on the continent, considered a really significant milestone for ESA and scientific exploration in general.
As director of science at ESA when Rosetta launched, David insisted that a small micro disk was fixed to it, for at the end of Rosetta’s mission to study 67P, Rosetta was destined to become the 2nd artefact to ‘land’ on a comet, its last journey. Etched on the micro disk is the 1st chapter of Genesis of 3 religions in 1000 languages and dialects – a 21 century Rosetta stone.
Mary Somerville
Allan's chosen subject this year Mary Somerville-the Lady Mathematical Astronomer, one of the first serious scientific woman of the 19th century, a ‘grand amateur', of independent means who could pursue her passion to a professional level. In and an age when scientific work was undertaken by men, very few women could be counted as equal to their male scientific peers.
Mary was born to Lt. George Fairfax and Margaret Fairfax in 1780 in Scotland. Her childhood was spent exploring the seaside of her hometown of Burntisland near Edinburgh. Her father was a Vice Admiral in the navy and whilst stationed in America during the war of independence was written to by one George Washington, who thought he may be related to the Fairfax’s. Back home Mary grew up very much ‘a tom boy’. She had a sharp sense of humour and could swear like a trooper - something learned off her uncle who had served in India. An algebra problem in a women's fashion magazine introduced her to mathematics. (Couldn’t imagine Vogue running anything like that nowadays) She was curious what the symbols meant. It was considered improper for a young lady show am interest in mathematics, and she had to secretly ask her brother's tutor to buy her a copy of Euclid's Elements, after overhearing that Elements formed the basis for understanding astronomy and other sciences. Far from being encouraged in reading, members of her family criticised her for spending time on this unladylike occupation, so she read in secret by candle light on a night, until she was caught out.
After retiring on a modest pension her father thought what Mary needed was a husband, so in 1804 when aged 24, Mary married a distant relative, Samual Greig, a Russian diplomatic naval attaché. He had a low opinion of Mary, and did not encourage or support her in her thirst for knowledge. The marriage was short; he died of fever a few years after they were wed. The death of her husband, although difficult and tragic, did however; afford Mary an opportunity quite rare to women of her time.
Mary found that widowhood and a comfortable inheritance had left her both emotionally and financially independent. She was free to study according to her personal convictions and returned to Edinburgh where she was given private tutorials in mathematics. She corresponded frequently with Scotsman William Wallace, who, at the time, was mathematics master at a military college.
Mary Somerville in Middle-age
Mary mastered J. Ferguson's Astronomy and became a student of Isaac Newton's Principia, reading Newton's Principia and, and at Wallace's suggestion, Laplace's Mécanique Céleste and many other mathematical and astronomical texts. She learned to the very highest level - to the French thinking on maths and was brilliant at it. She won prizes for solving maths puzzles in journals including a silver medal from the mathematical journal –The Mathematical Repository; she also acquired a 5ft Gregorian telescope.
Then in 1812 Mary married William Somerville, a doctor, and another distant family relative. William was extremely proud of Mary. The family moved from Edinburgh to London. Her husband was elected to the Royal Society and Mary and William moved in the leading scientific circles of the day. Their friends included George Airy, Maskelyne, John Herschel, William Herschel, George Peacock, and Charles Babbage. In addition they met with leading European scientists and mathematicians who visited London.
In 1817 William and Mary visited Paris and were introduced to the leading scientists there by Biot and Arago (whom they had met in London). Mary met Laplace, Poisson, Poinsot, Emile Mathieu and many others. All thought her to be charming and quite brilliant. They enjoyed the theatre, opera, visiting the fashion houses and going to balls, she became a real socialite. They then continued south, where she was fated in Germany, then onto Florence, Rome, Pompeii, she even had a private audience with the Pope...She was a Scottish protestant!
In 1824 en route through Italy, William was appointed as a physician at the Royal Hospital in Chelsea. Returning to London, Mary and William continued close contact with their many scientific friends. Mary Fairfax Somerville's scientific investigations began in the summer of 1825, when she carried out experiments on magnetism. In 1826 she presented her paper entitled "The Magnetic Properties of the Violet Rays of the Solar Spectrum" to the Royal Society. The paper attracted favourable notice and, aside from the astronomical observations of Caroline Herschel, was the first paper by a woman to be read to the Royal Society and published. She became known for her exceptional expository talent, even so, woman were still refused entry in the great libraries and noble institutions of the country. William had to write down whole chapters of books for Mary.
Then in 1826 Lord Brougham, Scottish Barrister, speaker of the house of Lords, Lord Chancellor and mad keen amateur scientist, on behalf of the Society for the Diffusion of Useful Knowledge, began correspondence with Mary through her husband, as social convention dictated, to persuade her to write a popularised rendition of Laplace's Mecanique Céleste and Newton's Principia. Mary undertook the project in secrecy. In 1831 ‘A Mechanism for the Heavens’ was published, more of a reinterpretation than a translation. It caused a sensation and the book became a required text for higher mathematics students. Her books were used to teach ‘real tuff science’ at Cambridge University.
Mary Somerville spent most of 1832-33 in Paris where she renewed old friendships with the mathematicians there, and where she worked on her next book; The connection of the physical sciences -an account of physical phenomena and connections among the physical sciences. This was published in 1834. Her discussion of a hypothetical planet perturbing Uranus in the sixth edition (1842) of this work led John Coach Adams to his investigation and subsequent discovery of Neptune. The book also fired the imagination a young Charles Darwin.
These projects helped firmly establish her in intellectual circles. She and Caroline Herschel were elected in 1835 to the Royal Astronomical Society, the first women to receive such an honor. She was granted honorary memberships to the Société de Physique et d'Histoire Naturelle de Genève (1834), The Royal Irish Academy (1834), and the Bristol Philosophical and Literary Society (1835) and eleven Italian scientific societies between 1840 and 1857. Sir Robert Peel, British prime minister from 1834-35 and again from 1841-46, awarded her a civil pension of 200 per annum.
In 1838 William resigned his appointment at Chelsea and in 1839 the Somerville’s returned to Italy, where amongst other exploits Mary climbed Mt Versuvius just a few weeks after it had erupted. Then in 1848, at the age of 68, Mary published yet another book in two volumes - an A-Z of the Earth’s surface entitled Physical Geography, the first modern work on the subject. It was an enormous best seller and was widely used in schools and universities until the early 20th century.
Many further honours were given to Mary as a result of this publication. She was elected to the American Geographical and Statistical Society in 1857 and the Italian Geographical Society in 1870. In 1870 the Royal Geographic society presented her with its Victoria Gold Medal.
Her last scientific book; Molecular and Microscopic Science, which was published in 1869 when Mary was eighty-nine, and was a summary of the most recent discoveries in chemistry and physics. In that same year she completed her autobiography, of which her daughter, Martha, published parts after her death. Even at the age of 90 Mary and Sir John Herschel, who himself was 75, were corresponding on why Lobsters glow in the dark - and if one could take a spectrum - truly incredible. In November of 1872 aged 92 Mary finally passed away. Apparently shortly before her death and befitting of an admirals daughter, having outlived her husband, most of her friends and all but one child, Mary is reported to have said - “ I am ready to go now, I am just waiting for the Blue Peter to be raised and I shall journey to distant shores, to make and renew acquaintances”
Mary Somerville was a strong supporter of women's education and women's suffrage. John Stuart Mill, the British philosopher and economist, organised a massive petition to parliament to give women the right to vote, he had Mary put her signature first on the petition. Somerville College in Oxford was named after her in 1879 because of her strong support for women's education, a fitting tribute to a quite extraordinary woman.
Sky Notes
In this month's Sky Notes:
Planetary Skylights
The Planet Venus dominates the evening twilight sky, a brilliant object across in the South-West. Through a telescope little can be discerned of the surface, however being an inferior planet (one that orbit’s inside earth’s orbit) Venus does exhibit a phase which is currently a shrinking half phase in nature. Venus reaches greatest eastern elongation on the 12th, the same evening it lies closest to Neptune. The pair should fit in the same telescopic view at low power, so if you miss the Mars conjunction (see below) you have another bite at Neptune. Over the course of the 1st and 2nd a slender crescent moon also lies in the vicinity making for a pleasing conjunction. The same occurs again on the last evening of January.
Mars resides upper left of Venus and is reasonably conspicuous to the naked eye, the ruddy hue a giveaway. Through a telescope Mars appears as a very small gibbous ball with little, if any, detail visible. Mars does however serve very nicely as a guide to the location of a far more distant planet, Neptune, which resides very close to the red planet in the sky during the last few days of 2016 and the start of 2017.
 01-Jan-2017, 17:00h:
(looking SSW): Mars and Neptune Click for full-sized image |
 02-Jan-2017, 17:15h:
(looking SSW): Mars, Neptune, Moon, Venus and Comet Click for full-sized image |
 19-Jan-2017, 07:15h:
(looking South): Moon, Jupiter, Saturn, Mercury Click for full-sized image |
On Jan 1stNeptune and Mars are separated by just 18 arc minutes, easily framed in the same low/medium eyepiece field through most telescopes. Neptune will have a tiny blue grey disk. The moon joins the party on the 3rd.
In the dawn sky Jupiter reigns supreme. Rising in the early morning hours, it is best placed an hour before sunrise, almost due south. Jupiter resides above the bright star Spica in Virgo, the pair joined by a waning crescent moon on the 19th forming a perfect line.
Mercury has a foray into the dawn sky during January, although it never strays far from the east horizon. It will be more conspicuous mid month onwards; 14th-23rd when it should be visible to the naked eye at mag - 0.5.
A ‘star’ of almost similar brightness residing to the upper right of Mercury is the planet Saturn, which is gradually moving up and out of the Sun’s glare. Although still a little close to the horizon, if you get chance, do try to have a look at Saturn through a telescope, it is worth the early rise effort’ View approximately 35mins before sunrise to catch both Saturn with Mercury. A very slim crescent moon passes above on the 25/26th.
Meteor Showers
Quarantids apparent source
(Click for full-sized image)
The year starts with one of the more prolific meteor showers, the Quadrantids, active between Jan 1- 6th. The short lived shower peak normally falls over the night of 3rd/4th, with best rates witnessed in the small hours; 02:00-04:00h.
Peak zenith hourly rates are in the 80-100 per hour bracket, but actual observed rates by an individual will be around the 20–30 mark. Quadrantids are often, fairly swift, producing occasional yellow-green fireballs.
Quadrantids appear to radiate from the now defunct constellation of Quadrans Muralis, which was removed from sky charts in 1922, but used to lie at the junction between Hercules, Bootes and Ursa Major. This position in the sky is located low to the N at the time of the peak, so do not concentrate on this aspect if viewing.
Comet 45P
Comet 45P Honda-Mrkos-Pajdusukova (45P HMP) may reach naked eye visibility during the first week of the New Year. As usual northern hemisphere observers are at a disadvantage with the comet low in the twilight sky.
Finder Chart for Comet 45P Honda-Mrkos-Pajdusukova, 01-15-Jan-2017
The best chance of spotting the comet is during the first few days of January. Look over to the SW where Venus is totally dominant. Mars lies approx 5 degrees upper left of Venus. Now imagine a line drawn from Mars thru’ Venus and extended just under twice that distance to the lower right.
The comet resides in this part of the sky (actually in Capricornus) View around 17:00-17:30h using binoculars. Hopefully you will come across a fuzzy blob with perhaps a tail. The comet is predicted to reach +6.5 magnitude; borderline naked eye, but we all know how fickle comets are, so you never know.
January 2017 Sky Charts
Click each image to see a full-size Sky Chart:
 |
 |
|
Looking North
Mid-January - 21:00h |
Looking South |
 |
 |
|
Looking East
Mid-January - 21:00h |
Looking West
Mid-January - 21:00h |
 |
 |
|
Overview (Northern Aspect)
Mid-January - 21:00h |
Overview (Southern Aspect)
Mid-January - 20:10h |
 |
 |
| Morning Looking North Mid-January - 06:45h |
Morning Looking South Mid-January - 06:45h |
 |
 |
| Morning Looking East Mid-January - 07:07h |
Morning Looking West Mid-January - 06:45h |
Additional Image Credits:
- Planets and Comets where not otherwise mentioned: NASA
- Sky Charts: Stellarium Software
In-Focus
In the second part of our tour through the winter sky we shall look at some more deep sky celestial treats to tempt you outside.
NGC 2392 ("Clown Face" or "Eskimo" Nebula") is 2 degrees up and right of the NGC 2420 Open Cluster, shown on the chart above.
NGC 2392 "Clown Face"
Double-shell Planetary Nebula
Click for full-sized image
To begin, locate the constellation of Gemini, the twins, whose two leading stars, Castor and Pollux ride quite high in the South-East sky. The object we are seeking is the Planetary Nebula - NGC 2392 or ‘The Clown face’ nebula, a telescopic object well worth observing. To find -follow the line of stars in Gemini extending away from Pollux.
The second star along, called Wasat, is our “jumping off” point. Place Wasat at the left side of the finder scope field and aim in the direction of a trio of stars (63 Geminorum). A tad further in this direction brings two stars into view; one of these looks out of focus and is the nebula. Under high magnification the greenish colour is quite distinct, but to see the patches that give this nebula its name is beyond the range of most backyard scopes. The nebula is approx 3,000 lightyears distant and is young just 2,000 years old.
Messier Finder Chart for M44 - Praesepe: "Beehive Cluster" and M67 "King Cobra Cluster)
M44 - Praesepe: "Beehive Cluster" in the Constellation of Cancer ("the Crab")
Our next object lies in Cancer, the Crab whose faint stars are found to the lower left of Castor and Pollux. On nights of good seeing and away from light pollution this object should be visible to the naked eye as a milky patch of light, it is M44 “the Beehive” or Praesepe open cluster. If you need directions it is located midway and a little to the right of two faint stars called the Asses. Even in binoculars or a finder scope some of the stars in this lumpy soup of light will be resolved. Through a scope this object is magnificent with over 70 stars being visible in a “milky haze” including many doublets and triplets some of which are orange -red in colour. In all the cluster contains over 400 members and lies 500 lightyears away, it is reckoned to be over 400 million years old.
M67 "King Cobra": thought to
be oldest Messier open cluster.
To find our next object, project down from the two stars called the Asses a distance equivalent to twice their separation to a spot just to the right of a dim 4th magnitude star in Cancer called Acubens. In binoculars or finder scope a small ball of light will be visible; this is the open cluster M67. This grainy ball is seen best under high magnification when many fainter stars can be resolved. M67 is unusual in that it is situated 1,500 Lyears above the galactic plane some 2500 lightyears away where the gravitational pull of other stars is much weaker, hence this open cluster has remained together. A good number of its 400 plus members have evolved into their Red giant stage, making M67 the oldest open cluster known - 7 to 10 billion years!
Next on the menu are a couple of triple star groupings, the first is Sigma Orionis which can be found directly below Alnitak - the bottom star of Orion’s belt. When viewed through a small scope (2-4 inch) 3 stars are visible arranged in a pleasing group, this becomes a quartet when larger scopes are used. Incidentally, we have all seen images of the Horsehead nebula – but to actually observe it, is quite tricky. A 10” scope or more, a light pollution filter, a really dark sky and patience, are required, or you can take long exposure images of the region around Alnitak, the nebula should stand out then, but it is rather small.
Moving on, look to the barren region to the left of the belt stars, this is the home of Monocerus the Unicorn. The star we’re after is Beta Monocerotis the left star of the two visible here. Once located this is a nice triplet made up of a white primary and two fainter blue companion stars arranged in a crooked line. Again in larger scopes this group becomes a quadruple system. It lies at a distance of 450 lighyears.
M46 and M47: Open Clussters in constellation Puppis
Our final objects all lie in Puppis - found to the left of Canis Major home to the brightest star - Sirius. The two open clusters of M46 and M47 reside two/ three binocular fields to the left of Sirius, and are visible as two adjacent misty patches. In small scopes M46 does not look as impressive as its neighbour M47 - a speckled hazy cloud, however larger scopes resolve M46 into hundreds of faint stars 5600 lightyears away. M47 is just 1500 lightyears distant.
From these two clusters travel almost due south and level with Wezen, the top star of a trio of bright stars some way below Sirius. Searching this area you will come across a faint concentrated nebulous patch of light - this is M93 an impressive cluster when viewed at high powers with over 3 dozen stars resolved. The cluster lies 3500 lightyears away and is roughly 100 million years old.
Events
Observe the night sky with us at the Bruce Observatory, Caedmaon College - Normanby campus (formally Whitby College).
Observing Nights are held weather permitting: check for a relatively clear sky before leaving home. If in doubt, Mark can be reached on tel 01947 605516.
Please note the college drive gate is now operated via a electronic key code - so anyone wishing to attend must be at the car park at the top of the drive by 19:00hrs, unless an arrival time has been arranged with Mark/Keith after 19:30hrs. Otherwise shout or bip car horn - we'll hear.
