Stargazer. Nene Valley Astronomical Society. M31 - The Andromeda Galaxy. November & December 2016

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1 Nene Valley Astronomical Society Stargazer November & December 2016 M31 - The Andromeda Galaxy Imaged By NVAS member Paul Blackman at a recent Chelveston Observing Evening.

2 Welcome to the latest edition of the Nene Valley Astronomical Society s Stargazer newsletter. Thank you for all the various comments and suggestions that I received following the introduction of your new look society newsletter last time out. Some of these ideas feature in this edition and I m looking at making some further alterations to coming editions. On Saturday 8th October, along with members from the Astronomy Section of the Northamptonshire Natural History Society, we hosted a public stargazing evening at Stanwick Lakes. Thank you to those members who were able to support this evening which unfortunately coincided with overcast skies again. Around forty visitors attended, which although considerably down from previous evenings, enjoyed a series of talks presented by Nick Hewitt, John McEvoy and myself. Stanwick Lakes do intend to hold another session to coincide with the BBC Stargazing Live series next year, the date of which has yet to be finalised. Looking ahead, we have a couple of excellent speakers visiting us at the November Sudborough and Chelveston meetings, details of which are on the next page, so please do come along to these. Attendance at Sudborough meetings has declined somewhat over the course of the last year and we have therefore decided to make some changes to these meetings from next year, with the emphasis moving away from visiting guest speakers, to more practically focused evenings. Depending on the attendance levels we may invite some guest speakers later next year to Sudborough, however the main programme of lectures will be at Chelveston meetings from January. Clear Skies, Steve Williams Co-ordinator: Steve Williams (astrosteveuk@yahoo.co.uk) Speaker Organiser: Peta Jellis Treasurer: David Jones Web Site: Tony Stock & Mick Price Meeting Refreshments: Alec Parker & Penny Smith

3 Society Meetings & Events Thursday 3rd November: An Introduction to Variable Star Observing. by Gary Poyner. Gary is one of the leading observers of variable stars having made hundreds of thousands of observations from his home in Birmingham. This evening Gary will explain more about this fascinating aspect of astronomy and how amateur observers can contribute to furthering our understanding of the variety of variable stars. Sudborough Village Hall, Main Street, Sudborough at 8pm. Admission 3. Friday 4th November: Observing session at Chelveston Village Hall from 8pm. To check that conditions will permit observing and that the session will proceed, please check our Twitter feed on the home page of our web site from 6.30 on the evening. Friday 11th November: Observing session at Chelveston Village Hall from 8pm. Details as 4th November. Friday 18th November: Observing session at Chelveston Village Hall from 8pm. Details as 4th November. Monday 21st November: A Comet s Tale by Dr Jon Shanklin. Dr Jonathan Shanklin, who recently retired as Director of the British Astronomical Association Comet Section, will describe some of the great comets of historical times, show the contribution of amateur observers to comet science and will look forward to any comets that may become easily visible in the near future. Chelveston Village Hall, Caldecott Road, Chelveston at 8pm. Admission 3. Friday 25th November: Observing session at Chelveston Village Hall from 8pm. Details as 4th November. Thursday 1st December: Astronomical Aspects meeting. An evening of members short presentations and the chance to share your recent observations. Sudborough Village Hall, Main Street, Sudborough at 8pm. Admission 2. Friday 2nd December: Observing session at Chelveston Village Hall from 8pm. Details as 4th November. Friday 9th December: Observing session at Chelveston Village Hall from 8pm. Details as 4th November. Friday 16th December: Observing session at Chelveston Village Hall from 8pm. Details as 4th November. Monday 19th December: Christmas Meeting featuring the Christmas Quiz and some festive merriment! Chelveston Village Hall, Caldecott Road, Chelveston at 8pm. Admission 2.

4 Friday 23rd December: Observing Evening at Chelveston Village Hall from 8pm. Details as 4th November. Thursday 5th January: Observing Orion - a look at the constellation. The Sky Guide will also be presented and the chance for members to present short talks. If clear, observing will take place outside, so bring your binoculars and telescopes. Sudborough Village Hall, Main Street, Sudborough at 8pm. Admission 2. Friday 6th January: Observing Evening at Chelveston Village Hall from 8pm. Details as 4th November. Monday 16th January: Accidental Death Of An Anarchist. Mike Frost the Historical Section Director of the British Astronomical Association is our speaker for this evening. Chelveston Village Hall, Caldecott Road, Chelveston at 8pm. Admission 3. Further information on our meetings and details of any late changes can be found on our website neneastro.org.uk. The top of the butte in this scene from the Mast Camera (Mastcam) on NASA's Curiosity Mars rover stands about 16 feet (about 5 meters) above the rover and about 82 feet (about 25 meters) east-southeast of the rover. Mastcam's right-eye (telephoto-lens) camera took the component images of this mosaic on Sept. 1, 2016, during the 1,448th Martian day, or sol, of Curiosity's work on Mars. Image Credit: NASA/JPL-Caltech/MSSS

5 A couple of shots from our Stargazing (aka Cloudgazing) at Stanwick Lakes on Saturday 8th October with members from the Astronomy Section of the Northamptonshire Natural History Society

6 Meeting Reports Our July meeting at Sudborough saw Dr Ann Bonnell from the Leicester Astronomical Society make her first visit to us. Ann s lecture was entitled The Search For Vulcan & Other Solar System Enigmas and looked at the search for a hypothetical planet between the orbit of Mercury and the Sun. The existence of Vulcan being proposed by the French mathematician Urban Le Verrier to explain the observed peculiarities in the orbit of Mercury. Our July meeting at Chelveston saw the return of Jerry Workman from London. This year Jerry spoke to us about Pluto and Other Small Bodies Of The Solar System showing us some of the images returned from the New Horizons fly-by mission of the Pluto system along with images taken by the Dawn spacecraft of minor planet Ceres and other asteroids including Vesta. Our program of guest lecturers took a break during August, however our regular meetings continued. At our Sudborough meeting in August, Alec Parker gave a talk on Meteors, Meterorites and Bolides whilst Steve Williams presented his guide to forthcoming events in the sky including the then forthcoming Perseid Meteor display. Our annual watch for Perseid meteors took place on the evening of Friday 12th August, despite the occasional promise of clear intervals, much of the time was spent watching the more common atmospheric feature of clouds. Nevertheless one of two meteors were spotted by some members. Our August meeting at Chelveston saw Alec Parker present a talk on Asteroids during which he explained the various types and showed images of a variety including Ceres, Vesta and Gaspra. A DVD was shown about the centre of a galaxy in Sagittarius and the evening was rounded up with Steve Williams with a brief look around the night sky. Our Sudborough September meeting was to have seen Dr Martin Braddock speak to the group. As we subsequently found out afterwards, Dr Braddock was involved in a minor car accident on his way to us and was unfortunately unable to make it to us. Instead Steve Williams stepped in with a Sky Guide presentation, with the rest of the meeting being a chance for some astronomical chat. Dr Mahesh Anand was our speaker at the September Chelveston meeting with a lecture entitled The Moon and the Search for Water. Unfortunately I was unable to make this particular one, however by all accounts the lecture was well received. Dr Anand has forwarded the following web links for those who d like some further information: OU s Moons MOOC (next start is on 31 st October 2016): ESA website for lunar exploration: The virtual microscope project:

7 Sky Notes - November & December Taken from heavens-above.com, the above Starchart shows how the night sky looks on November 1st at 11pm and November 15th at 10pm. The southern part of the sky is dominated by the great square of Pegasus with the neighbouring constellation of Andromeda and it s famous galaxy of M31 passing across the meridian at the time of the chart. Towards the north-west can be found the asterism of the Summer Triangle (Vega, Deneb and Altair) with the latter now rapidly approaching the western horizon. Cassiopeia now lies directly overhead offering a good (if neck breaking) chance to view the Milky Way and the various star clusters that abound. The East and South-Eastern aspect is now taking on a rather winter looking appearance with Auriga, Orion, Taurus and Gemini now on view.

8 The Moon First Quarter - 7th November & 7th December Full Moon - 14th November & 14th December Last Quarter - 21st November & 21st December New Moon - 29th November & 29th December A lunar occultation of the first magnitude star Aldebaren takes place above the western horizon at around 5.15am on December 13th. Mercury is not visible during November. There is a chance to spot it in the south-western evening sky during December, particularly around the time of Greatest Eastern Elongation on December 11th, when it will be around 4 degrees high at 40 minutes after sunset. Venus is on view in the south-western evening sky as twilight falls. There is a challenging opportunity to view Venus, Saturn and the Moon on the evening of November 3rd, look at around 5.30pm; you will need an unobstructed southwestern horizon for this as Venus is only 2.5 degrees high at this time with Saturn 6 degrees to the right. The visibility of Venus does however rapidly improve through November and December,with our neighbouring world dominating the south-western sky for several hours after sunset by Christmas. Mars lies close to the meridian, low in the south as darkness falls at the start of November amongst the stars of Sagittarius. The Moon passes to the upper left of Mars on the evening of November 6th. Mars itself is now a 7 arc second diameter dot through the eyepiece (probably too small now to make out surface details visually) and shines at magnitude +0.4 at the start of November. During December it continues to fade and becomes confined to the south-western quadrant. On New Years Eve, Mars and Neptune close to within half a degree apart. Jupiter is becoming visible above the Eastern horizon shortly before dawn. The situation continues to improve through November and by mid-december, Jupiter is visible from around 1.30am. Saturn reaches conjunction with the Sun on December 10th and is not visible at this time, save for its challenging appearance with Venus on November 3rd (above). Uranus is visible at magnitude 6 in the constellation of Pisces in the evening sky. An easy spot in binoculars, it s greenish hue is visible through a telescope. Neptune lies amongst the stars of Aquarius at magnitude 8. The Moon passes close to Neptune on the evening of 9th November, when both objects will appear in the same field of view as a pair of 10x50 binoculars - an excellent opportunity to see Neptune if you ve yet to track down this icy giant.

9 Apologies that our regular Eagle s Eye guide by Dave Eagle is not included in this newsletter, however printed copies will be available for collection at our meetings and can also be downloaded from Dave s web site at eagleseye.me.uk The above Star chart shows how the night sky will look on December 1st at 11pm, December 15th at 10pm and December 31st at 9pm. Taken from heavens-above.com

10 The Kuiper Belt & Beyond Alec Parker When Pluto was discovered in 1930 by Clyde Tombaugh, it was regarded as the ninth planet in our Solar System. At this time no-one had any idea about further objects in this region. In 1951 Gerard Kuiper suggested that there may be a disk shaped region beyond Neptune containing minor planets and smaller rocky/icy objects which was a source for short-period comets. In 1978 a moon was discovered orbiting Pluto by James Christy at the U.S Naval Observatory. This moon was named Charon. There was still no idea that there were many other bodies in this region. Subsequently, more moons were found orbiting Pluto by the Hubble Space Telescope and NASA s New Horizon fly-by mission last year. In 1986 an astronomer named David Jewitt was uncomfortable with the idea that there was nothing beyond Pluto and began a search for other objects. He was assisted in this by a graduate student from MIT called Jane Luu. They toiled away for five years up until 1992 when they discovered their first Kuiper Belt Object (KBO) nicknamed Smiley and designated 1992QB1. What they didn t realise in 1986 and for a while was that the technologies available could not detect very,very distant and very, very dim objects. With the advent of better technologies with greater resolutions discoveries of such bodies was possible. Their discovery was made with a 2.2 metre telescope on Mauna Kea in Hawaii. So, Jewitt and Luu were the first discoverers of the physical Kuiper Belt. Now I have to say that I thought the Kuiper Belt was a reasonably straightforward region - but - No! With the subsequent discovery of many other objects (1,000+), the regions beyond Neptune and the objects therein were given designations to distinguish their behaviours. So, simply put, there was the Kuiper Belt, the Scattered Disk (also called Scattered Kuiper Belt) and the Oort cloud. The Kuiper Belt is a ring-doughnut shaped region beyond Neptune, while the Oort cloud is a spherical area surrounding the solar system and extending almost a quarter of the way to our nearest star - Proxima Centauri. The Oort Cloud has NOT been directly observed and is still a hypothetical region! Standard Kuiper Belt Objects (KBO s) are dwarf planets, or minor planets, or smaller, that have circular orbits outside of Neptune s orbit and in the plane (ecliptic) that all the major planets orbit in. Typically like 1992QB1 - also called Cubiwanos - after the QB designation! Scattered (Kuiper) belt objects are as above, but whose orbits are markedly inclined to the major planets orbits and are also quite elliptic (oval) in nature and come close to Neptune.

11 There are many other sub-divisions of these objects with different behaviours, too many to catalogue here! Objects from the Oort Cloud are characterised as comets that appear but once in the solar system and have orbits that take thousands of years. As yet no object has been confiemd from this region. In 1992 at University of California, Berkley, Jane Luu bumped into a friend called Michael E. Brown, who was studying for a doctorate in astronomy, where she mentioned that they (she and Dave Jewitt) had just found the Kuiper Belt. This sowed a seed in Michael Brown that set him off some years later in the search for more objects beyond Neptune. As with Jewitt and Luu it took some years before Michael Brown (CalTech) developed the techniques that enabled him, with Chad Trujillo (Gemini Observatory) and David Rabinowitz (Yale), to find what they were looking for. Brown and his team made probably the most significant discoveries of objects in the Kuiper Belt which raised many questions about the origins of our solar system and how it was created. These were Quaoar in 2002, Sedna in 2003, Orcus and Haumea in 2004, Eris, MakeMake and Dysnomia in Eris is roughly the same size as Pluto and more massive. It was this discovery that led to the IAU reclassifying Pluto to Dwarf Planet status. Sedna is currently the most distant known object in the solar system, with an orbital period of 11,400 years. Interestingly it is as it closest to the Sun currently which is lucky because it would have been too far away to be detected at any other point! Its orbit is very, very long and elongated. For all the latest on the Kuiper Belt and beyond, check out the IAU Minor Planet Centre website at minorplanetcenter.net/ Artists Impression of the Dwarf Planet Eris.

12 Members Observations This section of the Stargazer Newsletter is for NVAS members to showcase recent observations. Contributions are welcome from all and can be in the form of an image, sketch or description of anything that you ve observed of an astronomical nature. First is this lunar sketch submitted by Tony Verney:

13 Two images submitted by Paul Blackman. Top - The beautiful double star Albireo in Cygnus and Below - M27 the Dumbbell Nebula in Vulpecula. Both taken on 23rd August.

14 Two shots of the Summer Milky Way taken by Steve Williams. Top - Cygnus and Lyra. Lower - Aquila to Sagittarius.

15 Upcoming Meteor Showers The final couple of months see four meteor showers to look out for with the Taurids, Leonids, Geminids and the Ursids. First up are the Taurids which are active from mid-september through to mid- November. This is a relatively weak meteor shower producing no more than a dozen meteors per hour which can sometimes produce some bright fireballs when we pass through the denser part of the stream of material. The Taurids are associated with Comet Encke and whilst the Earth s orbit misses the densest part of the stream this year, observers will still see some meteors from this shower, some of which will be quite slow moving which can help those trying to image the meteors. Best observing will be during the early part of November before the Moon becomes too prominent in the evening sky. Next up come the Leonids, which are active from November 14th through to November 21st. Best rates will be on the night of November 17th/18th, however you need to be prepared to stay up late as the radiant for this meteor shower does not clear the Eastern horizon until almost mid-night. Associated with Comet Swift-Tuttle, this meteor shower can produce very high rates, however this is not next expected until the early 2030 s. This year the bright gibbous Moon will cause major interference for the Leonids, however if you can observe the sky with the Moon behind a fence or building, then you should be able to see some meteors. At the time of maximum, the peak Zenithal Hourly Rate is expected to reach meteors. After the Perseids in August, the Geminids are probably the second most observed meteor shower of the year. Active between December 6th and 17th, they reach maximum this year during the late evening of December 13th. Unusually for meteor streams, the Geminids are associated with debris from asteroid 3200 Phaethon. At maximum, the Geminids produce a Zenithal Hourly Rate of around 100 and with the radiant above the horizon from early evening through to dawn they can be observed right through the night if you are so inclined! This year however, the Geminids have a bright Full Moon to contend with, so as with the Leonids you will need to observe with your back to the Moon or else with a building to block the brightest of the light to see the brightest of this years Geminids. The final meteor shower of 2016 are the Ursids. The radiant lies near the star Kochab in Ursa Minor and is active from December 17th to the 25th, reaching maximum on the night of December 23rd/24th. This radiant is circumpolar so is available all night, however best observing conditions will be before moonrise at around mid-night. The Ursids are associated with Comet 8P/Tuttle and typically produce a Zenithal Hourly Rate of ten meteors at maximum. If you are successful in observing any of these meteor showers, then why not send your reports in for the next Stargazer Newsletter!

16 This view shows Saturn's northern hemisphere in 2016, as that part of the planet nears its northern hemisphere summer solstice in May Saturn's year is nearly 30 Earth years long, and during its long time there, the Cassini spacecraft has observed winter and spring in the north, and summer and autumn in the south. The spacecraft will complete its mission just after northern summer solstice, having observed long-term changes in the planet's winds, temperatures, clouds and chemistry. Cassini scanned across the planet and its rings on April 25, 2016, capturing three sets of red, green and blue images to cover this entire scene showing the planet and the main rings. The images were obtained using Cassini's wide-angle camera at a distance of approximately 1.9 million miles (3 million kilometers) from Saturn and at an elevation of about 30 degrees above the ring plane. The view looks toward the sunlit side of the rings from a sun- Saturn-spacecraft angle, or phase angle, of 55 degrees. Image scale on Saturn is about 111 miles (178 kilometers) per pixel. Image Credit: NASA/JPL-Caltech/Space Science Institute Nene Valley Astronomical Society Find us on Facebook and Follow Us On Twitter!