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Venus in the Pleiades Cluster

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A bit cloudy for photos tonight but it was nice to briefly see Venus travelling past the Pleiades star cluster (M45). 9.30pm. Sony RX100 IV, f2.8, 4 sec, ISO 1600, 70mm

Dark Skies of the Tywi Valley, Carmarthenshire

October 1, 2016 Leave a comment

We stayed at a remote cottage in the Tywi Valley north west of Rhandirmwyn in Carmarthenshire for a week and I had a couple of opportunities to spend some time under the dark skies available here. To the naked eye there is no light pollution at all within the Tywi valley and the Milky Way is easily seen when your eyesight is dark adapted. The higher sensitivity of the camera sensor picks up some light glow from Rhandirmwyn village and a larger amount from the town of Llandovery, which lies some 10km distant. The area is well known for dark skies with a couple of sites recommended here Dark Sky Discovery Sites UK including the YHA hostels at Ty’n-y-cornel and Dolgoch located to the north of the Llyn Brianne reservoir.

Here are some photos taken from the cottage on clear, but occasionally cloudy, nights with the Fuji X100s at 28mm, F2, ISO 6400, 15 – 25 second exposures.

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Above: Looking south through thin cloud with some light pollution from Rhandirmwyn and Llandovery evident. Delphinus (upper right edge) with the head of Pegasus (centre) and parts of Aquarius.

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Above: Looking north east at the constellations Cassiopeia (top) and Perseus (centre) with the bright star Capella in Auriga near the bottom of the photo

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Above: Looking west towards the Allt Ty’n-y-ddol ridge with Ursa Major (the Plough) just above the dark ridge line. The Pole Star – Polaris (top right) and Ursa Minor and Draco to the left of Polaris.

 

 

The Dark Skies of Anglesey, North Wales

March 11, 2016 Leave a comment

Spent a few days up on Anglesey near Penmon where they have stunning dark skies so I took the opportunity to do a little astrophotography from the back garden of the cottage, which overlooked the sea to the north. Orion was prominent in the western sky while to the south Jupiter was rising above the roof and through the trees. Many star clusters were visible with the naked eye including the Double Cluster, three clusters in the southern half of Auriga and M44 (The Beehive) near Gemini. The Andromeda Galaxy was easy to find in the north.

The Isle of Anglesey AONB is currently working towards gaining Dark Sky Reserve Status and you can follow their progress here The view was quite spectacular on a moonless night with stars from horizon to horizon. Light pollution was minimal for naked eye viewing, particularly to the north and west. The main problem for photographers will be the large number of passenger jets heading east – west in the north and it was difficult to take a photo which did not have a plane trail in it.

All images taken with the Sony RX100, F1.8, 28mm, ISO 3200, 8 second exposures.

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Orion in the west

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Jupiter rising through the lower branches of the tree

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Jupiter gleaming over Penmaenmawr and the Snowdonia Mountains

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Looking west to Benllech and Amlwch with the constellations Cassiopeia, Perseus  and Andromeda. The faint smudge just right of centre is the Andromeda Galaxy.

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Looking north west to Cassiopeia and Andromeda with the Milky Way faintly glowing

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The Plough looking north east

Comet Catalina – Now Visible in Binoculars

January 16, 2016 Leave a comment

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Above: Comet Catalina on 15/1/2016 at 23.31 pm from the back garden. Sony RX100, 28mm, F1.8, ISO 3200, 8 seconds. A crop of the image below.

Comet C/2013 US 10 Catalina will be at it’s closest approach to Earth on Sunday 17th January at about 110 million kilometres away. It is already speeding away from the Sun and back out of the Solar System and losing brightness fast. With a Full Moon coming up on January 24th this really is your last chance to see the comet with binoculars from your back garden as the moonlight will make it very difficult to see. I had a look last night in wonderful clear skies and the comet was easily visible in 8 x 30 binoculars.

The photograph above gives a pretty accurate idea of what you will see through binoculars. Look for a faint grey fuzzy splodge with a slightly brighter core to the left of the star Alkaid which forms the tip of the handle in the constellation Ursa Major (also called the Big Dipper, The Plough, The Saucepan).  If you are stepping outdoors from a brightly lit house your eyes will need 5 – 10 minutes to fully adjust to the dark conditions and resolve the faintest stars and the comet. Turn off all outside lights and don’t use torches as these will ruin the ability of your eyes to adjust and see fainter objects. Just stand and look at all the amazing constellations around you for a bit then zoom in with the binoculars and let your eyes become accustomed to the darkness. Scan the area to the left of the star Alkaid (use the finder chart below) and you should pick up the faint grey smudge of light that makes up the comet. Feast your eyes on this small object as it is the last time humans will see it. Catalina will never return due to its orbital path.

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Above: The position of the comet to the left of the bright star Alkaid in Ursa Major 15/1/16 23.31 pm

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Above: Finder chart courtesy of freecharts.com to help you locate the comet between the 15th and 22nd January

While you are out there under the stars do also take a look behind you to the south and the fabulous Orion constellation with the Hyades and Pleiades star clusters to the west of it. It was really glistening last night in a very dark and clear sky from our house.

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Above: The constellation Orion to left with the Hyades (right of centre) and Pleiades (right) star clusters. Image taken 15/1/16 23.39 pm Sony RX100, 28mm, F1.8, ISO 3200, 8 seconds.

Happy Christmas ! A Portrait of the Constellation Orion

December 24, 2015 Leave a comment

So Christmas is upon us again and I would just like to wish all followers and readers of the blog a very Happy Christmas ! Here is a photograph I took the other night while waiting for the aurora to appear. I happened to turn around and there was the winter constellation Orion high in the south east above The Breidden hills with the arrow shaped Hyades cluster just above it to the right and then the smaller Pleiades cluster right at the top edge of the photo on the right.

It has been a great year of astronomy for me with the 95% solar eclipse in March, then a full lunar eclipse in September, lots of great comets and supernovae  and numerous sightings of the aurora over Wales. Here’s hoping 2016 is just as exciting !

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NGC 2264 The Christmas Tree Cluster

December 19, 2015 Leave a comment

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NGC 2264 in the constellation Monoceros is sometimes called the Christmas Tree Cluster due to the vaguely triangular group of blue stars towards the top of this image with the large blue-white star S Monocertis, near the left centre of the photo, forming the base of the tree trunk. The cluster actually lies within a dense region of star-forming gas known as the Cone Nebula and you can just make out some of the pale white gas around the stars. Hydrogen alpha astronomy filters show up the surrounding gas much better in red, but here I wanted to focus on the star cluster itself.

The cluster was first discovered by William Herschel in 1784 and at magnitude 4.5 some of the stars are visible with the naked eye, but the cluster really pops out with 8x binoculars and even more with a 3″-4″ telescope.

Image taken 19/12/15 3.21am New Mexico time with iTelescope.net T3. 1 x 300 sec Colour. RA: 06h 40m 59.9s DEC: 09° 54′ 00″ (J2000). Processed with Maxim DL5 and Photoshop CS2.

 

Venus with the Pleiades and Hyades Open Star Clusters 14th April 2015

April 14, 2015 Leave a comment

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I couldn’t resist another go at Venus passing the Pleiades cluster tonight, but this time I took a wider view and included the Hyades open cluster too. The Hyades is the V of stars to the left with the much closer red giant star Aldebaran glowing brightly at the top of the V. The Hyades cluster is about 625 million years old and the nearest open cluster to the solar system. Please click on the image to enlarge it as the small image above is heavily compressed by WordPress.

Image taken 14/4/15 20.27 UTC+1 Sony RX 100, ISO 1600, f.4.9, 37mm, 2.5 sec Luminance x 11. Stacked in Deepskystacker 3. Processed in Photoshop CS2.

Venus and the Pleiades Cluster 12th April 2015

April 12, 2015 Leave a comment

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Dashed out into the back garden just before 9pm to catch this lovely close encounter between Venus and the Pleiades open star cluster (M45) low in the west at 9.02pm. A close conjunction like this occurs every eight years in mid April. Image taken with a Canon 350d and Tamron LD DI 70-300mm zoom lens at 70mm (then cropped) ISO 400 3.2 seconds.

Star Cluster NGC 6603 in the M24 Small Sagittarius Star Cloud

There’s nothing particularly impressive or image worthy happening on the Sun at the moment so instead of concentrating on our own star I thought I would show you a few thousand ! The bright knot of stars at the centre of the image below is the open star cluster NGC 6603 buried deep in the heart of the brightest part of the M24 Small Sagittarius Star Cloud, close to the centre of our galaxy.

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NGC 6603 was discovered by John Herschel around 1825-33 and includes 30 stars with an approximate age of 200 million years. The component stars shine at magnitude 11 or 12 and the larger stars dotted around its location in the foreground are magnitude 6.5 – 7.5. The surrounding star cloud as a whole is aged between 200 and 600 million years old. Lets take a closer look at the NGC 6603 cluster………

NGC 6603 cropped There’s a lovely chain of stars in the cluster heading towards the top right of centre.

Image taken 28/3/15 4.56am New Mexico time 10.56am UT on iTelescope T3 (Tak TOA 150, SBIG ST-8300C) RA: 18h 18m 24.1s DEC: -18° 24′ 00″ (J2000)

Berkeley 20 & Berkeley 29 – Old Open Clusters and the Evolution of the Milky Way

April 30, 2012 Leave a comment

Above: Berkeley 20 Open Cluster in Orion. Imaged  with iTelescope T3  7/10/11  4:06:04 am New Mexico time (UTC -7) RA: 05h 32m 36.0s DEC: 00° 11′ 11″ (J2000) TAK TOA 150, SBIG ST2000 SMC 2x 600 sec Bin 1

Yes I know this isn’t one of the most exciting photographs visually, but that little knot of stars just to the right of centre is one of the top 20 in terms of the oldest star clusters in our galaxy (6 billion years old) and one of the most distant (15.8 kiloparsecs or 51,000 light years). Along with Berkeley 29, which currently holds the record for the most distant open cluster in our galaxy at 22.6 kpc or 73,000 light years, these veteran star communities are providing exciting new evidence for the formation of the outer disk of the Milky Way and perhaps even suggest that our galaxy may be a cannibal !

Current research using photometry and spectroscopy of the stellar makeup of these and a number of other distant clusters (Berkeley 31, NGC 2141, NGC 2808, NGC 5286) suggests that something odd is going on. While they typically have low iron metal content this content should decrease the further you get from the galactic centre, but recent papers have suggested that beyond 40,000 light years the iron content bottoms out and actually remains constant out to the edge of the galaxy at about 30% of the Sun’s iron content. On top of that the clusters have stars with a high Oxygen/Magnesium to Iron ratio which is a signature derived from short-lived massive stars that have gone supernova, so what is going on ? An intriguing possibility is that these distant open clusters may be aliens in our midst, derived by our galaxy either swallowing up the stars from another galaxy in a merger event, or stars accreting to the outer disk of the Milky Way in a collision event with a passing gas cloud that triggered new star formation.

Evidence is also gathering that these older clusters lie in a dispersed arc-like structure in the outer disk known as the Galactic Anti-center Stellar Structure (GASS), sometimes called the Monoceros Ring. It is thought that this structure  could be the remnant of a merger with a dwarf galaxy about 5 billion years ago, similar to the Canis Major dwarf spherical galaxy that was discovered to be merging with our galaxy back in 2003.

Above: Berkeley 29 Open Cluster in Gemini – the most distant open cluster in the Milky Way. Imaged  with iTelescope T3  7/10/11  5:01 am New Mexico time (UTC -7) RA: 06h 53m 04.0s DEC: 16° 55′ 39″ (J2000).  TAK TOA 150, SBIG ST2000 SMC 2x 600 sec Bin 1

With the advent of the 4.1 metre VISTA infrared telescope coming online at the European Southern Observatory last year we may soon discover older and more distant open clusters that will fill out this picture of early galactic evolution. Up to September 2011 VISTA had discovered 96 new clusters previously hidden by thick dust clouds and it is estimated that there may be as many as 30,000 open clusters still waiting to be found in our galaxy – exciting times ahead !!

Categories: Stars & Star Clusters