Nene Valley Astronomical Society. Stargazer. July & August M57 - The Ring Nebula In Lyra.

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1 Nene Valley Astronomical Society Stargazer July & August 2016 M57 - The Ring Nebula In Lyra

2 Welcome to the latest edition of the Nene Valley Astronomical Society s Stargazer newsletter. After a few months break we are relaunching your newsletter as a new look bi-monthly publication which will be distributed as before by PDF, but from now on will be available at our events for collection as an A5 full colour publication. As previously, we ll be featuring Dave Eagle s sky notes, providing the latest society news and notes and featuring contributions from NVAS members and friends. I very much hope that the new look Stargazer will encourage more people to contribute. So, if you d like to contribute an article, write a report on a meeting, or share your observations with your fellow members, then please get in touch. Over recent months we ve been enjoying a whole range of visiting guest speakers at our meetings,including Professor Andrew Norton, Mike Frost, Jerry Stone, Dr Mike Leggett and Dr Robin Catchpole. Our speaker organiser, Peta Jellis has been doing sterling work and will shortly be starting organise the lecture programme for So if you have any suggestions for speakers or topics you d like to see covered, then please let Peta know. We have a couple of guest speakers visiting us during July. Dr Ann Bonnell will be at Sudborough on 7th July and Jerry Workman will be at Chelveston on 18th July. Further information is on the next page. 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 7th July: The Search For Vulcan and Other Solar System Engimas by Dr Ann Bonnell. Sudborough Village Hall, Main Street, Sudborough at 8pm. Admission 3. The history of astronomy is littered with observations and theories about planets and moons that were subsequently shown not to exist. This evening Dr Ann Bonnell from the Leicester Astronomical Society will tell you about some of these e.g. the hypothetical planet Vulcan that was thought to be closer to the Sun than Mercury. You will also hear about how some sightings did in fact make some important contributions to astronomy. Monday 18th July: Pluto and Other Small Bodies Of The Solar System by Jerry Workman at Chelveston Village Hall, Caldecott Road, Chelveston at 8pm. Admission 3. This evening Jerry will talk about Asteroids including information on Vesta and Ceres. Ceres and Vesta are the two most massive residents of the asteroid belt, Vesta is a rocky body, while Ceres is believed to contain large quantities of ice. He will then talk about comets including the latest mission to comet 67P/CG(Churyumov-Gerasimenko) from the Rosetta mission finishing his talk on Pluto from New Horizons mission and other planets and moons. Thursday 4th August: The Sky Guide & Astronomical News along with short talks. Sudborough Village Hall, Main Street, Sudborough at 8pm. Admission 2. Friday 12th August - Perseid Meteor Watch & Observing Session at Chelveston Village Hall, Caldecott Road, Chelveston from 8.30pm. Monday 15th August: The Sky Guide & Astronomical News along with short talks. Chelveston Village Hall, Caldecott Road,Chelveston at 8pm. Admission 2. Thursday 1st September: The Fermi Paradox and The Search For Extra-Terrestrial Life by Dr Martin Braddock. Sudborough Village Hall, Main Street, Sudborough at 8pm. Admission 3. Friday 2nd September: Observing Evening at Chelveston Village Hall, Caldecott Road, Chelveston from 8pm onwards. To check that conditions will permit observing, please check our Twitter feed on the home page of our web site from 6.30 on the evening.

4 Mercury Transit Report On the afternoon of Monday 9th May, a number of NVAS members met up at Chelveston Village Hall to view the Mercury solar transit. Conditions were very favourable for much of the afternoon and members were able to watch the slow progress of the tiny disc of Mercury as it progressed across the Sun s disc through a variety of telescopes. By late afternoon, however cloud started to obscure the view and by around 6.30pm (around an hour before the transit ended) we were totally obscured. Nevertheless an enjoyable session was had by all. The next Mercury transit occurs on the afternoon of 11th November 2019, although the Sun will set for UK observers with Mercury still on the solar disc. Below: Paul Blackman s image of the Mercury transit on 9th May

5 Steve Williams view of the Mercury transit from Chelveston, shortly before the clouds rolled in.

6 Eagle s Eye - July 2016 Taken from heavens-above.com, the above Starchart shows how the night sky looks on July 1st at 11pm and July 15th at 10pm. High above at the zenith, Draco sprawls between Ursa Minor and Hercules. The distinct asterism of The Lozenge marks the dragons head. In the south below Hercules lies another giant, Ophiuchus. This area is swarming with globular clusters. Even lower in the south, the head of Scorpius is at its highest, just poking up from the southern hemisphere. Towards the north the bright yellow star Capella can be seen just skirting the horizon. In the western sky, Leo is now just about to disappear, as is Virgo.

7 The Summer Triangle of Vega, Deneb and Altair, in the constellations of Lyra, Cygnus and Aquila respectively, is now visible, bringing a fabulous region of our Milky Way into view. This area abounds with nebulae and clusters. With darker nights now starting to draw in, let s look forward to some clearer skies this coming autumn and some great observing / imaging. The Moon: New - July 1st Full - July 9th First Quarter - July 12th Last Quarter - July 26th The crescent Moon will be visible in the western evening sky on the 5th & 6th and in the eastern morning sky on the 30th & 31st. The Moon will be nearby Jupiter on July 8th & 9th, Spica on July 11th, Mars on July 14th, Saturn on July 15th & 16th, Neptune on July 23rd and Aldebaren on July 29th. The Planets: MERCURY Passes superior conjunction on the 7th and is unlikely to be viewed this month as it stays far too close to the Sun. VENUS Still far too close to the Sun to be seen this month. MARS Now past its best and shrinking rapidly as the distance from Earth increases. Shrinks from 16.3 to 13.1 seconds of arc throughout the month. It stays low to the horizon from the UK and the Earth s atmosphere will be very turbulent interfering with seeing small details. However the patient observer and webcam imager should be able to tease out some of its most distinctive surface features. JUPITER Now low down in the western sky after dark. At magnitude -1.4 lying below the tail of Leo. This majestic planet will soon be lost in the evening twilight. SATURN Located a little above Antares in Scorpius in the southern sky after dark. It does remain low throughout this years apparition, but the rings are wide open and is still a beautiful site even in a small telescope. The atmosphere will inhibit seeing fine detail. URANUS Moving into the eastern morning sky before dawn in the constellation pf Pisces. At magnitude 6.15 it is just below naked eye visibility and requires binoculars or a small telescope to identify.

8 NEPTUNE Visible in the southern sky morning sky in the constellation of Aquarius. At a faint magnitude 7.7 it will require binoculars or a small scope to spot it amongst the faint background stars. PLUTO Visible as a 14th magnitude star around midnight hiding amongst the numerous background stars within the Milky Way in Sagittarius. For more details and my latest activities visit my Web site: Dave Eagle Taken from heavens-above.com, the above Starchart shows how the sky will look on August 1st at 11pm and August 15th at 10pm.

9 Fireworks in Skyrocket Galaxy NASA's Hubble Space Telescope has captured a spectacular fireworks display in a small, nearby galaxy. A firestorm of star birth is lighting up one end of the diminutive galaxy Kiso The dwarf galaxy is shaped like a flattened pancake, but because it is tilted edge-on, it resembles a skyrocket, with a brilliant blazing head and a long, star-studded tail. Kiso 5639 is a rare, nearby example of elongated galaxies that occur in abundance at larger distances, where we observe the universe during earlier epochs. Astronomers suggest that the frenzied star birth is sparked by intergalactic gas raining on one end of the galaxy as it drifts through space. "I think Kiso 5639 is a beautiful, up-close example of what must have been common long ago," said lead researcher Debra Elmegreen of Vassar College, in Poughkeepsie, New York. "The current thinking is that galaxies in the early universe grow from accreting gas from the surrounding neighbourhood. It's a stage that galaxies, including our Milky Way, must go through as they are growing up." Observations of the early universe, such as Hubble's Ultra Deep Field, reveal that about 10 percent of all galaxies have these elongated shapes, and are collectively called "tadpoles." But studies of the nearby universe have turned up only a few of these unusual galaxies, including Kiso The development of the nearby starmaking tadpole galaxies, however, has lagged behind that of their peers, which have spent billions of years building themselves up into many of the spiral galaxies seen today.

10 Elmegreen used Hubble's Wide Field Planetary Camera 3 to conduct a detailed imaging study of Kiso The images in different filters reveal information about an object by dissecting its light into its component colors. Hubble's crisp resolution helped Elmegreen and her team analyze the giant star-forming clumps in Kiso 5639 and determine the masses and ages of the star clusters. The international team of researchers selected Kiso 5639 from a spectroscopic survey of 10 nearby tadpole galaxies, observed with the Grand Canary Telescope in La Palma, Spain, by Jorge Sánchez Almeida and collaborators at the Instituto de Astrofisica de Canarias. The observations revealed that in most of those galaxies, including Kiso 5639, the gas composition is not uniform. The bright gas in the galaxy's head contains fewer heavier elements (collectively called "metals"), such as carbon and oxygen, than the rest of the galaxy. Stars consist mainly of hydrogen and helium, but cook up other "heavier" elements. When the stars die, they release their heavy elements and enrich the surrounding gas. "The metallicity suggests that there has to be rather pure gas, composed mostly of hydrogen, coming into the star-forming part of the galaxy, because intergalactic space contains more pristine hydrogen-rich gas," Elmegreen explained. "Otherwise, the starburst region should be as rich in heavy elements as the rest of the galaxy." Hubble offers a detailed view of the galaxy's star-making frenzy. The telescope uncovered several dozen clusters of stars in the galaxy's star-forming head, which spans 2,700 light-years across. These clusters have an average age of less than 1 million years and masses that are three to six times larger than those in the rest of the galaxy. Other star formation is taking place throughout the galaxy but on a much smaller scale. Star clusters in the rest of the galaxy are between several million to a few billion years old. "There is much more star formation going on in the head than what you would expect in such a tiny galaxy," said team member Bruce Elmegreen of IBM's Thomas J. Watson Research Center, in Yorktown Heights, New York. "And we think the star formation is triggered by the ongoing accretion of metal-poor gas onto a part of an otherwise quiescent dwarf galaxy." Hubble also revealed giant holes peppered throughout the galaxy's starburst head. These cavities give the galaxy's head a Swiss-cheese appearance because numerous supernova detonations -- like firework aerial bursts -- have carved out holes of rarified superheated gas. The galaxy, located 82 million light-years away, has taken billions of years to develop because it has been drifting through an isolated "desert" in the universe, devoid of much gas.

11 What triggered the starburst in such a backwater galaxy? Based on simulations by Daniel Ceverino of the Center for Astronomy at Heidelberg University in Germany, and other team members, the observations suggest that less than 1 million years ago, Kiso 5639's leading edge encountered a filament of gas. The filament dropped a large clump of matter onto the galaxy, stoking the vigorous star birth. Debra Elmegreen expects that in the future other parts of the galaxy will join in the star-making fireworks show. "Galaxies rotate, and as Kiso 5639 continues to spin, another part of the galaxy may receive an infusion of new gas from this filament, instigating another round of star birth," she said. From Science Daily Hubble Confirms New Dark Spot On Neptune The Hubble Space Telescope has observed a new vortex in the upper atmosphere of the planet Neptune. The images taken on 16th May 2016 show the dark vortex below some bright clouds in the planets southern hemisphere. The dark spot measures roughly 3,000 miles across. The vortex is similar to the 'Great Dark Spot' that was observed by the Voyager 2 spacecraft which flew past the planet in 1989 and are high pressure systems in the Neptunian atmosphere. Numerous other high altitude clouds can also be seen in the images at various latitudes.

12 Jupiter s Vivid Aurora Astronomers are using the NASA/ESA Hubble Space Telescope to study auroras -- stunning light shows in a planet's atmosphere -- on the poles of the largest planet in the Solar System, Jupiter. This observation programme is supported by measurements made by NASA's Juno spacecraft, currently on its way to Jupiter. Jupiter, the largest planet in the Solar System, is best known for its colourful storms, the most famous being the Great Red Spot. Now astronomers have focused on another beautiful feature of the planet, using the ultraviolet capabilities of the NASA/ESA Hubble Space Telescope

13 The extraordinary vivid glows shown in the new observations are known as auroras. They are created when high energy particles enter a planet's atmosphere near its magnetic poles and collide with atoms of gas. As well as producing beautiful images, this programme aims to determine how various components of Jupiter's auroras respond to different conditions in the solar wind, a stream of charged particles ejected from the Sun. This observation programme is perfectly timed as NASA's Juno spacecraft is currently in the solar wind near Jupiter and will enter the orbit of the planet in early July While Hubble is observing and measuring the auroras on Jupiter, Juno is measuring the properties of the solar wind itself; a perfect collaboration between a telescope and a space probe. "These auroras are very dramatic and among the most active I have ever seen," says Jonathan Nichols from the University of Leicester, UK, and principal investigator of the study. "It almost seems as if Jupiter is throwing a firework party for the imminent arrival of Juno." To highlight changes in the auroras Hubble is observing Jupiter daily for around one month. Using this series of images it is possible for scientists to create videos that demonstrate the movement of the vivid auroras, which cover areas bigger than the Earth. Not only are the auroras huge, they are also hundreds of times more energetic than auroras on Earth. And, unlike those on Earth, they never cease. Whilst on Earth the most intense auroras are caused by solar storms -- when charged particles rain down on the upper atmosphere, excite gases, and cause them to glow red, green and purple -- Jupiter has an additional source for its auroras. The strong magnetic field of the gas giant grabs charged particles from its surroundings. This includes not only the charged particles within the solar wind but also the particles thrown into space by its orbiting moon Io, known for its numerous and large volcanoes. The new observations and measurements made with Hubble and Juno will help to better understand how the Sun and other sources influence auroras. While the observations with Hubble are still ongoing and the analysis of the data will take several more months, the first images and videos are already available and show the auroras on Jupiter's north pole in their full beauty. From Science Daily

14 NASA s Dawn Spacecraft Completes Primary Mission NASA's Dawn spacecraft has completed its historic primary mission, during which the probe became the first ever to visit a dwarf planet and the first to orbit two different bodies beyond the Earth-moon system. Dawn's primary mission came to an end on 30th June. But the spacecraft isn't shutting down; Dawn is still studying the dwarf planet Ceres from orbit, and the probe may soon head out to visit a third cosmic object, if NASA approves a proposed extended mission. The $467 million Dawn mission launched in September 2007 to study Vesta and Ceres, the two largest objects in the main asteroid belt between Mars and Jupiter. Dawn orbited the 330-mile-wide (530 kilometers) Vesta from July 2011 through September 2012, and the probe has been circling the 590-mile-wide (950 km) Ceres since March Dawn's observations are helping researchers better understand how these two very different worlds formed and evolved, mission team members have said. "Dawn has revealed that while Vesta is a dry body, Ceres could be as much as 25 percent water ice by mass," NASA officials said in a statement. "Dawn also discovered many intriguing features at both bodies Vesta is home to a mountain whose height is more than twice that of Mount Everest, and Ceres has a crater called Occator with mysterious bright features that continue to spark scientific investigation."

15 During the course of its primary mission, Dawn traveled more than 3.5 billion miles (5.6 billion km), orbited Vesta and Ceres a combined 2,450 times and beamed home a total of 69,000 images of both bodies, NASA officials said. The spacecraft's work isn't done, however. Dawn is still observing Ceres, and mission team members recently proposed to fly the probe to a third object in the asteroid belt on an extended mission. (Dawn scientists have not revealed the identity of the targeted body.) NASA must decide soon whether or not to approve the extension; if Dawn doesn't leave Ceres by July 12, the spacecraft won't have enough hydrazine fuel left to make the journey to the third object. If Dawn stays put at Ceres, it should have enough hydrazine to keep operating until early 2017, mission officials have said.

16 Stargazing Evenings At Chelveston Village Hall On the evening of Friday 12th August, we will be holding our annual Perseid Meteor Observing session at Chelveston Village Hall from 8.30pm onwards. Although the Moon will be above the horizon for most of the evening, it will be setting by around 11.30pm, so we should be able to see a reasonable number of Perseid meteors, given that the shower reaches maximum activity on the evening of the 12th/ morning of the 13th. Additionally Saturn and Mars will be observable, so bring your telescope along. Our main Stargazing eveningsre-commence on Friday evenings from 8pm with effect from 2nd September. As previously these will take place on clear Friday evenings or those where it s decided that there is at least a reasonable prospect of observing taking place. To determine whether a session is taking place please either follow us on Twitter or check the Twitter feed on the front page of our website, where an announcement will be made after 6.30 on the evening. We also plan to hold additional short notice sessions, on various evenings this Autumn,when the weather forecast looks promising. Such sessions will be announced around 24 hours before, by on Twitter and Facebook. Hopefully these will allow us all the opportunity to do some more observing from an out of town location this Autumn! Steve Williams

17 On the evening of Saturday 8th October, we are returning to Stanwick Lakes for our second public stargazing event of the year. This time we are being joined by our friends from the Astronomy Section of the Northampton Natural History Society, who will be helping us to increase the number of telescopes for the public to use and build on the success of this popular event. Further details will be announced at our meetings and in the next edition of the Stargazer. Members Observations As a regular feature of this newsletter, we encourage NVAS members to submit recent observations for publication. These can be in the form of images, a sketch or a written description. First up is a recent image of Jupiter taken by Paul Blackman.

18 Left: Saturn imaged by Steve Williams on 8th June 2016 through a 6 Refractor. Below: Jupiter imaged by Steve Williams on 2nd May 2016 through a 6 Refractor.

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20 Mars imaged on 12th May 2016 by the Hubble Space Telescope. Nene Valley Astronomical Society Find us on Facebook and Follow Us On Twitter!