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Found 24 results

  1. Observations of the Sculptor Galaxy ( NGC 253 ) by William and John Herschel ......... Part 2. Observations of "Caroline's Galaxy" by Sir John Herschel, 1830's Sir John Herschel, the only child of Mary Baldwin and Sir William Herschel, was born in 1792 when his father was in middle age and already famous as one of world's leading astronomers. Having excelled in school, and no doubt inspired by his famous elders, John Herschel decided upon a career as a 'man of science' and set out to pursue a wide range of interests; with one particular focus being a continuation of the study of the heavens commenced by his father and aunt, Caroline Herschel. In 1820, with the assistance of his father, John Herschel supervised the construction of a new telescope at Slough in England. As described in the extract below ( from a paper presented to the Royal Society in 1826, titled "Account of some observations made with a 20-feet reflecting telescope ... " ), the telescope had a polished metal mirror with clear aperture of 18 inches, focal length of 20 feet and was modelled on the same design created by his father. It is this telescope, in the 1820’s and early 30’s, following the death of his father and the return of his aunt Caroline to Hanover, that John Herschel used to 'sweep' the night sky and extend the catalogue of nebulae and clusters of stars that was published by his father ( see W. Herschel's Catalogue of One Thousand new Nebulae and Clusters of Stars ). On the 1st of July 1833, having complied sufficient observations, John Herschel presented to the Royal Society an updated list of the positions and descriptions of the Nebulae and Clusters of Stars that he had thus far observed. As noted in the introduction to the paper published in the Philosophical Transactions, he had planned to wait before publishing until he had complied a fully comprehensive general catalogue of objects visible from the south of England. However, due to his expectation of “several more more years additional work” needed to complete the task and his assessment that he now was in a position to address, at least in part, the then current “... want of an extensive list of nebulae arranged in order of right ascension ...”, he elected to present his list, “ ... simply stating the individual results of such observations as I have hitherto made ... “. It was not until October 16, 1863, some thirty years later, that Sir John would deliver to the Royal Society his General Catalogue of Nebulae and Clusters of Stars. As well as introducing many objects that had not previously been recorded, Sir John’s list of 1833 included a re-examination of, and in some cases a small correction to, the positions of many of the deep sky objects observed by his father and noted down by his aunt. One of these re-visited objects was, unsurprisingly, the large and bright nebula discovered by Caroline Herschel in 1783 and recorded in Sir Williams’s catalogue as V.1 / CH 10 ( object number one, of class five ( very large nebulae ) / Caroline Herschel #10 ). In total, John Herschel records around 2500 observations of nebulae and clusters of stars in his 1833 paper; with observation #61 being V.1, the “ Sculptor Galaxy “ . The measured position of V.1is given in RA and the angle from the north celestial pole ( all reduced to epoch 1830.0 ). The description can be interpreted by reference to the legend in the paper. Thus, “ A vL mE vB neb “ becomes “ A very large, much extended, elliptic or elongated, very bright nebula “. He also notes that in addition to this observation, #61, noted down from sweep #306, V.1 was also observed in sweep #292, “but no place was taken”. The figure to which he refers , figure 52, is included towards the back of his paper and is a sketch he made of the Sculptor Galaxy. to be continued ...
  2. The Silver Coin Galaxy ( NGC 253 ) in the Sculptor constellation - updated. 24th March 2017: New version that was reprocessed ( again ) to improve colour balance ... original version below ( colours are a little too yellow ) ( click on image to see full size ) The Silver Coin Galaxy ( NGC 253 ) in the Sculptor constellation ( aka the Silver Dollar or Sculptor Galaxy ). Caroline Herschel in 1783 was the first to recordthis bright ‘nebula’ in an area of the southern sky that Nicolas de Lacaille had called the “Apparatus Sculptoris” or “the sculptor’s studio”. Whilst relatively close to us compared to the billions of far more distant galaxies in the Universe, the great size of the “Sculptor Galaxy” and the huge distances involved are still hard to comprehend. To put this into some perspective, the light that is just now reaching one edge of the great disc left the opposite edge when the Earth was in the grip of last great Ice Age 70,000 years ago and the light we now see has been travelling towards us for over 11 million years. Details: NGC 253 - "Silver Coin" or "Sculptor" galaxy. RA 00 48 23, DEC -25 11 52. Skywatcher Quattro 10" f4 Newtonian telescope. Skywatcher AZ Eq6 GT Mount. Orion Short Tube 80mm guide scope & auto guider - PHD2. Baader MPCC Mark 3 Coma Corrector & no filter. Nikon D5300 (unmodified). Field of view (deg) ~ 1.35 x 0.90. 20 x 180 sec ISO 800, long exp noise reduction on. Pixinsight & Photoshop. 4th November 2016 updated version 17 March 2017
  3. The Sculptor or Silver Coin Galaxy ( NGC 253 ) in the Sculptor constellation - re-processed from the original subs The Sculptor Galaxay ( NGC 253 ) ( Please click / tap on image to see larger and sharper ) .................... The Silver Coin Galaxy ( NGC 253 ) in the Sculptor constellation ( aka the Silver Dollar or Sculptor Galaxy ). Caroline Herschel in 1783 was the first to recordthis bright ‘nebula’ in an area of the southern sky that Nicolas de Lacaille had called the “Apparatus Sculptoris” or “the sculptor’s studio”. Whilst relatively close to us compared to the billions of far more distant galaxies in the Universe, the great size of the “Sculptor Galaxy” and the huge distances involved are still hard to comprehend. To put this into some perspective, the light that is just now reaching one edge of the great disc left the opposite edge when the Earth was in the grip of last great Ice Age 70,000 years ago and the light we now see has been travelling towards us for over 11 million years. Details: NGC 253 - "Silver Coin" or "Sculptor" galaxy. Catalogue location: RA 00 48 23, DEC -25 11 52. From Image Solver: Image centre: RA 00 47 33.4 Dec. -25 17 11.1 Focal length: 1008.5 mm Field of view: 1d 19' 2.2" x 53' 0.3" Skywatcher Quattro 10" f4 Newtonian telescope. Skywatcher AZ Eq6 GT Mount. Orion Short Tube 80mm guide scope & auto guider - PHD2. Baader MPCC Mark 3 Coma Corrector & no filter. Nikon D5300 (unmodified). Field of view (deg) ~ 1.35 x 0.90. 20 x 180 sec ISO 800, long exp noise reduction on. Pixinsight & Photoshop. November 4, 2016 re-processed from original subs ( including Photometric Colour Calibration ) - September 9, 2017 ........... Details of Sculptor Galaxy from SkySafari for the 4th of November 2016 around 10pm local time ............. Annotated version ( using Pixinsight ImageSolver and Annotation scripts ) Sculptor Galaxy ( NGC 253 ) - annotated The cyan tags ( 35 or so ) relate to galaxies recorded in the Principal Galaxies Catalogue. The white tags are brighter stars as recorded in the Tycho-2 Catalogue. The number beneath is the magnitude of the referenced star. .......... Link to previous version below ...
  4. Also known as the Theta Carinae Cluster, The Southen Pleiades is a very bright open cluster in the Carina constellation. It was discovered by Abbe Lacaille during his visit to South Africa in 1752. Containing around 60 stars, IC 2602 shines with an overall magnitude of 1.9 and its brightest member is Theta Carinae with a visual magnitude of 2.7. This cluster of young blue stars is relatively close to us at "only" 479 light years. 5 May 2018 The Southern Pleiades ( IC 2602 ) in Carina ( please click / tap on image to see larger and sharper ) ......... Image details: Orientation: North is up Telescope: Orion Optics CT12 Newtonian ( mirror 300mm, fl 1200mm, f4 ). Corrector: ASA 2" Coma Corrector Quattro 1.175x. Effective Focal Length / Aperture : 1470mm f4.7 Mount: Skywatcher EQ8 Guiding: TSOAG9 Off-Axis-Guider, Starlight Xpress Lodestar X2, PHD2 Camera: Nikon D5300 (unmodified) (sensor 23.5 x 15.6mm, 6016x4016 3.91um pixels) Location: Blue Mountains, Australia Moderate light pollution ( pale green zone on darksitefinder.com map ) Capture ( 5 May 2018 ): 14 sets of sub-images with exposure duration for each set doubling ( 1/30th sec to 240 sec ) all at ISO250. ( 22 x 240sec + at least 10 each forthe other durations ) Processing: Calibration: master bias, master flat and master dark Integration in 14 sets HDR combination Pixinsight May 2018
  5. The Jewel Box ( NGC 4755 ) is an open cluster of mostly hot young blue-white stars that appears to the unaided eye as a bright 4th magnitude star close to the Southern Cross. Only visible from southern latitudes, the Jewel Box was first recorded by Nicolas Louis de Lacaille during his visit to South Africa in 1751 and was later described by Sir John Herschel as "a casket of variously coloured precious stones" - hence the name "Jewel Box". The Jewel Box open star cluster ( ngc 4755 ) in Curx ( please click / tap on image to see larger and sharper ) Please see here for image details.
  6. The Jewel Box ( NGC 4755 ) is an open cluster of mostly hot young blue-white stars that appears to the unaided eye as a bright 4th magnitude star close to the Southern Cross. Only visible from southern latitudes, the Jewel Box was first recorded by Nicolas Louis de Lacaille during his visit to South Africa in 1751 and was later described by Sir John Herschel as "a casket of variously coloured precious stones" - hence the name "Jewel Box". The Jewel Box Open Cluster ( ngc 4755 ) in the Crux constellation. ( please click / tap to see larger and sharper ) ........... Image details: Orientation: North is up Telescope: Orion Optics CT12 Newtonian ( mirror 300mm, fl 1200mm, f4 ). Corrector: ASA 2" Coma Corrector Quattro 1.175x. Effective Focal Length / Aperture : 1470mm f4.7 Mount: Skywatcher EQ8 Guiding: TSOAG9 Off-Axis-Guider, Starlight Xpress Lodestar X2, PHD2 Camera: Nikon D5300 (unmodified) (sensor 23.5 x 15.6mm, 6016x4016 3.91um pixels) image Plate Solver script version 5.0 =========== Resolution ........ 0.586 arcsec/px Rotation .......... 0.000 deg Focal ............. 1375.43 mm Pixel size ........ 3.91 um Field of view ..... 58' 49.3" x 39' 17.8" Image center ...... RA: 12 53 40.040 Dec: -60 21 02.81 ========== Location: Blue Mountains, Australia Moderate light pollution ( pale green zone on darksitefinder.com map ) Capture ( 5 May 2018 ): 11 sets of sub-images with exposure duration for each set doubling ( 1/8th sec to 120 sec ) all at ISO250. ( 10 x 120sec + at least 10 each forthe other durations ) Processing: Calibration: master bias, master flat and master dark Integration in 11sets HDR combination
  7. “The Blue Bunny Nebula” .......... Edit: 27 Jan 2018 - updated again to try to draw more faint nebulosity out of the background; ( NGC 2359 - Thor’s Helmet ) ( please click / tap on image to see larger and without compression artefacts ( and double click on that image if you what to see it as I posted it ! ) ) ......... Edit: 24 Jan 2018 - stars a little brighter and tighter with no change to the rest of the image ( NGC 2359 - Thor’s Helmet ) ( please click / tap on image to see larger and without compression artefacts ( and double click on that image if you what to see it as I posted it ! ) ) ................. original: Thor's Helmet ( NGC 2359 ) in the constellation Canis Major Thor’s Helmet ( Duck Nebula, NGC 2359 ) ( please click / tap on image to see larger ) This HDR image shows the bright nebula Thor’s Helmet in a sea of colourful stars against a background of red from dust and HA emissions. The stars in this image range from the brightest ( bottom right, HD 56501 ) at magnitude +7.7 to around +20 or more. HDR capture and processing allows all of the stars to be portrayed in colour without any burnt-out highlights. The colours of the stars and nebula are as close as I can get them to their "true colours" by using a "daylight colour balance" and allowing for the extinction of blue-green due to atmospheric absorption/scattering ( mean altitude during capture ~ 60deg ). The blue star in the centre of the bubble of expanding stellar material is HD 56925 ( WR7 ) - a massive, unstable and short-lived Wolf-Rayet star that one day will detonate in a supernova. Image details: NGC 2359 Thor’s Helmet / Duck Nebula: Magnitude +11.5, RA (2000.0) 7h 15m 37s, Dec -13deg 12' 8", approx. 1800 light years away HD 56925 / Wolf-Rayet 7 ( WR7 ) ( blue 11.5 mag star at centre of “bubble” ) Haffner 6 ( open ster cluster centre left of image ) Plate Solution: Resolution ........ 1.318 arcsec/px Rotation .......... 0.00 deg ( North is up ) Focal ............. 1398.41 mm Field of view ..... 57' 40.8" x 38' 29.0" Image center ...... RA: 07 18 36.509 Dec: -13 11 53.38 Telescope: Orion Optics CT12 Newtonian ( mirror 300mm, fl 1200mm, f4 ). Corrector: ASA 2" Coma Corrector Quattro 1.175x. Effective Focal Length / Aperture : 1410mm f4.7 Mount: Skywatcher EQ8 Guiding: TSOAG9 Off-Axis-Guider, Starlight Xpress Lodestar X2, PHD2 Camera: Nikon D5300 (unmodified) (sensor 23.5 x 15.6mm, 6016x4016 3.9um pixels) Location: Blue Mountains, Australia Moderate light pollution ( pale green zone on darksitefinder.com map ) Capture ( 18 & 19 Jan 2018 ) 9 sets of sub-images with exposure duration for each set doubling ( 1s to 240s ) all at ISO 250. 116 x 240s + 5 each @ 1s to 120s Processing ( Pixinsight - 20 Jan 18 ) Calibration: master bias, master dark and master flat Integration in 9 sets HDR combination arcSinH stretch
  8. Nearby spiral galaxy NGC 4945 in the constellation Centaurus. ( click on image to see full size ) ( This is an update of my image of NGC 4945 with an additional 22 x 360sec images at ISO400. ) NGC 4945 in the constellation Centaurus is a large spiral galaxy about the size of the Milkyway and around 13 million light years from Earth. It is shown here nearly edge-on and is accompanied in the image by a number of far more distant galaxies; the brightest of which is the 10th magnitude elliptical galaxy NGC 4976 (centre left of the image) which is around 30 million light years away. Links: https://500px.com/MikeODay http://photo.net/photos/MikeODay Details: RA 13h 06.5m, Dec -49 deg 33.5' Skywatcher Quattro 10" f4 Newtonian Skywatcher AZ Eq6 GT Mount Guiding: Orion Shortube 80 guidescope, Starshoot Autoguider, PHD2 Baader MPCC Mark 3 Coma Corrector Hutech IDAS D1 light pollution filter Nikon D5300 (unmodified) Long exposure noise reduction on 10 x 200sec @ ISO400 (19 Mar 2016) 22 x 360sec @ ISO400 ( 1 May 2016) Pixinsight Includes: NGC 4945 ( mag +9.3 ) NGC 4945A ( mag +13.3 ) NGC 4976 ( mag +10.0 ) PGC 45001 ( mag + 14.1 ) PGC 45317 ( mag + 14.2 ) PGC 45373 ( mag + 18.0 ) PGC 479454 ( mag + 15.9 ) PGC 480158 (mag + 16.8 ) Previous version :
  9. Barnard's Galaxy ( NGC 6822 ) in the constellation Sagittarius ( final version - well, at least until I can get more data ) ( click on image to see larger ) Barnard's Galaxy is one of a number of dwarf galaxies relatively near to us in our Local Group of galaxies. Similar in structure to the Small Magellanic Cloud, Barnard's galaxy is thought to be about half the size and around eight times as far away at 1.6 M Light Years. Weather permitting I hope to add more subs to help bring the faint detail further out from the sky background. Details: Barnard's Galaxy ( NGC 6822 ). Skywatcher Quattro 10" f4 Newtonian telescope. Skywatcher AZ Eq6 GT Mount. Orion 80mm f5 guide scope and auto guider - PHD2. Baader MPCC Mark 3 Coma Corrector, no filter. Nikon D5300 (unmodified). Field of view (deg) ~ 1.35 x 0.90. ISO400, 14bit NEF, Long Exp. NR on. 40 x 180sec (1/3 before & 2/3 after zenith) 25 Aug 16. Processed in PixInsight and finished off in Photoshop. re-processed to increase contrast and brightness of galaxy and a slight increase in overall sharpness. Links: https://500px.com/MikeODay http://photo.net/photos/MikeODay
  10. Jupiter & Peniel Heugh - Merry Christmas from Scottish Borders! by mikeyscope, on Flickr Looking like the star of Bethlehem planet Jupiter shines brightly in conjunction with Hyades & Pleiades star clusters in this early morning scene looking west with daylight fast approaching over the Waterloo Monument on Peniel Heugh, Scottish Borders Pentax K5 Pentax DA 17-70mm F4.0 AL (IF) SDM Exp 30 secs iso 800
  11. Sir John Herschel at the Cape of Good Hope Having spent the years 1825 to 1833 cataloguing the double stars, nebulae and clusters of stars visible from Slough, in the south of England, John Herschel, together with his family and telescopes, set sail from Portsmouth on the 13th of November 1833 bound for Cape Town. As detailed below, in an extract from his book, the family enjoyed a pleasant and uneventful voyage and arrived some 5 months later at Table Bay with all family and instruments in good condition. Reading on however, one might very well think that it might not have ended so well had they but left shortly after ... “... (iii.) Accordingly, having- placed the instrument in question, as well as an equatorially mounted achromatic telescope of five inches aperture, and seven feet focal length, by Tulley, which had served me for the measurement of double stars in England; together with such other astronomical apparatus as I possessed, in a fitting condition for the work, and taken every precaution, by secure packing, to insure their safe arrival in an effective state, at their destination, they were conveyed (principally by water carriage) to London, and there shipped on board the Mount Stewart Elpliinstone, an East India Company's ship, Richardson,Esq. Commander, in which, having taken passage for myself and family for the Cape of Good Hope, we joined company at Portsmouth, and sailing thence on the13th November, 1833, arrived, by the blessing of Providence, safely in Table Bay, on the 15th January, 1834, and landed the next morning, after a pleasant voyage, diversified by few nautical incidents, and without seeing land in the interim. It was most fortunate that, availing himself of a very brief opportunity afforded by a favorable change of wind, our captain put to sea when he did, as we subsequently heard that, immediately after our leaving Portsmouth, and getting out to sea, an awful hurricane had occurred from the S. W. (of which we experienced nothing), followed by a series of south-west gales, which prevented any vessel sailing for six weeks. In effect, the first arrival from England, after our own, was that of the Claudine, on the 4th of April, with letters dated January 1st.(iv.) ...” “Result of Astronomical Observations, Made During the Years 1834, 5, 6, 7, 8, At the Cape of Good Hope ... “ by Sir John Herschel, 1847 John Herschel rented a property and set up the twenty foot reflector near Table Mountain, at a site, that was then, just outside of Cape Town. The Twenty Feet Reflector at Feldhausen, Cape of Good Hope, South Africa, 1834 This telescope was made by Herschel in England and transported, along with his other instruments, by ship to Cape Town and then inland to Feldhausen. The telescope is a Newtonian reflector, built to William Herschel’s design, with a focal length of 20 feet and clear aperture of 18 1/4 inches ( f13 ). The location of the telescope was established by careful survey to be: lat 33d 55’ 56.55”, long 22h 46’ 9.11” W ( or 18.462 deg E ). The site of the great telescope was memorialised by the people of Cape Town by the erection of a granite column that is still there today. ............. Observations of the Sculptor Galaxy Amongst his many thousands of observations made from Cape Town, of nebulae, clusters of stars, double stars, the sun, etc., Sir John Herschel records that he observed V.1 ( CH10 - Caroline’s Nebula - the Sculptor Galaxy ) during two different “sweeps” and gave it the number 2345 in his South African catalogue. Sweeps: 646 - 20th November 1835; 733 - 12th September 1836 At the latitude of Feldhausen, and on these dates, the Sculptor galaxy would have been at an altitude around 80 degrees above the northern horizon when near the meridian ( which was where the telescope was pointed during Herschel’s “sweeps” ). The sight afforded from this location, with the Sculptor Galaxy almost at the zenith, must have been significantly brighter and clearer than the Herschels had thus far been granted from its location way down near the horizon south of Slough. .......... Other Obsevations by John Herschel from Cape Town Also observed by John Herschel in 1835 were the people and animals that inhabit the moon ... The Great Moon Hoax of 1825 - “Lunar Animals and other Objects, Discovered by Sir John Herschel in his Observatory at the Cape of Good Hope ... “
  12. Observations of the Sculptor Galaxy ( NGC 253 ) by William and John Herschel The very large and bright 'nebula' discovered by Caroline Herschel in 1783, that we now know as the Sculptor Galaxy, was observed a number of times by her 'dear brother' Sir William Herschel and by her 'beloved nephew' Sir John Herschel, Baronet. Some of these observations were recorded and published in the Philosophical Transactions of the Royal Society and, with respect to those by Sir John in South Africa, in the book of Astronomical Observations at the Cape of Good Hope. ......... Part 1. Observation of the 'class V nebula', H V.1, by Sir William Herschel, 1783 In 1782, with the fresh patronage of King George III, William Herschel, together with his sister Caroline, undertook the not inconsiderable task of transferring his astronomical equipment from Bath to Datchet ( near Windsor ) in England. Shortly afterwards, in 1983, Sir William began a "sweep of the heavens" with the very large Newtonian telescope of his design and construction. With this mighty telescope's twenty foot focal length and clear aperture of a little over eighteen and half inches, William was able to see fainter objects and smaller detail than any other astronomer of that time. ( source: The Scientific Papers of Sir William Herschel, Vol.1 ) ...... On the 30th of October, 1783, in the course of one of his "sweeps" with the twenty-foot telescope, Sir William Herschel observed Caroline's 'nebula' and noted down ( or perhaps more likely, dictated to Caroline ) a description of what he saw and a reference to its position relative to a 4th magnitude star in the Piscis Austrainus constellation, #18 Pis. Aust. ( with reference to Flamsteed's Catalogue ( or HD 214748 , HIP 111954 as we might call it )). Over the course of the next three years, Sir William would go on to view the Sculptor Galaxy a total of seven more times; as recorded in his paper "Catalogue of One Thousand New Nebulae and Clusters of Stars", presented to the Royal Society on the 27th of April 1786. ( Source ) Sir William's somewhat cryptic notes can be translated by reference to the key provide in his paper and doing so reveals the following: Class: V. ( very large nebula ) Number: 1 Observed ( by WH ): 30 Oct 1784 Reference star: 18 Piscis Austrainus ( Flamsteed's Catalogue; the best reference for the time - we might use epsilon Pis. Aust. or HD 214748 / HIP 111954 ) Sidereal direction rel. to star ( following or leading ): following star Sidereal time rel. to star: 128 min 17 sec Declination direction rel. to star: north of star Declination amount rel. to star: 1deg 39min Observed: 8 times ( up until April 1786, the date of the paper ) Description: - cB: "confidently bright" - mE: "much extended" - sp: "south preceding" - nf: "north following" - mbM: "much brighter middle" - size: 50' x 7 or 8' " CH" denotes that it was discovered by his sister Caroline Herschel The note he refers to expands on details of Caroline's discovery ... ...............................................
  13. Spiral Galaxy NGC 6744 in Pavo NGC 6744 is a Milky Way like barred spiral galaxy in the constellation Pavo. Visible only from lower latitudes, the light we see now left this galaxy around 25 million years ago. NGC 6744 in Pavo ( please click / tap on image to see larger and sharper ) Capture Details: North is up. Telescope: Orion Optics CT12 Newtonian ( mirror 300mm, fl 1200mm, f4 ). Corrector: ASA 2" Coma Corrector Quattro 1.175x. Effective Focal Length / Aperture : 1400mm f4.7. Mount: Skywatcher EQ8. Guiding: TSOAG9 Off-Axis-Guider, Starlight Xpress Lodestar X2, PHD2 . Camera: Nikon D5300 (unmodified) (sensor 23.5 x 15.6mm, 6016x4016 3.9um pixels). Location: Blue Mountains, Australia Moderate light pollution ( pale green zone on darksitefinder.com map ). Capture ( 16, 17, 19 Sept. 2017 ). 9 sets of sub-images with exposure duration for each set doubling ( 1s to 240s ) all at ISO800. 85 x 240s + 5 each @ 1s to 120s. Processing ( Pixinsight - 5-17 Nov 2017 ). Calibration: master bias, master flat and no darks. Integration in 9 sets. HDR combination PhotometricColorCalibration Arcsinh stretch ( function written by Mark Shelley ) Image Plate Solver - NGC 6744 - Sept 17, 2017 =================================== Resolution ........ 0.586 arcsec/px ( full size image ) Rotation ............ 0.001 deg. Focal ................. 1372.24 mm. Pixel size ........ ..3.90 um. Field of view ..... 58' 30.3" x 38' 59.0". Image center ...... RA: 19 09 46.591 Dec: -63 51 13.44 ==================================
  14. Galaxy Centaurus A ( NGC 5128 ) in the southern constellation Centaurus ( please click / tap on image to see full size ) ............ Updated again - to try to bring out more faint detail ... ............ Updated images ... ............. Originals ... ( 100% crop ) Centaurus A is relatively near to us in the local group of galaxies and is around 11 Million light years away. The unusual shape of Centaurus A is believed to be due to an ancient collision between a large elliptical galaxy and a much smaller spiral galaxy. With an apparent magnitude of +6.8, Centaurus A is the fifth brightest galaxy in the night sky and in the middle of the 20th century it was identified as being the strongest radio source in the Centaurus constellation. Details: Galaxy - Centaurus A ( NGC 5128 ) Image ( Nova.astrometry.net ): Center (RA, hms): 13h 25m 28.924s Center (Dec, dms): -43° 01' 25.486" Size: 60.5 x 41.1 arcmin Orientation: Up is -89.9 degrees E of N Telescope: Orion Optics CT12 Newtonian ( mirror 300mm, fl 1200mm, f4 ). Corrector: ASA 2" Coma Corrector Quattro 1.175x. Effective Focal Length / Aperture : 1410mm f4.7 Mount: Skywatcher AZ Eq6 GT Guiding: TSOAG9 Off-Axis-Guider, Starlight Xpress Lodestar X2, PHD2 Camera: Nikon D5300 (unmodified) (sensor 23.5 x 15.6mm, 6016x4016 3.9um pixels) Format: 14bit NEF Long exposure noise reduction: off Filter: none Calibration: No darks, just master bias and master flat HDR combination of eight sets of exposures (27, 28 & 29 April 2017): 85 x 240 sec ISO 800 16 x 120 sec ISO 800 16 x 60 sec ISO 800 16 x 30 sec ISO 800 16 x 15 sec ISO 800 16 x 8 sec ISO 800 16 x 4 sec ISO 800 16 x 2 sec ISO 800 Pixinsight May 2017 Links: 500px.com/MikeODay photo.net/photos/MikeODay www.flickr.com/photos/mike-oday
  15. The Wishing Well Cluster ( NGC 3532 ) in the constellation Carina ( click on image to see full size / best resolution ) This large bright open cluster, when seen through a small telescope, looks like a collection of brightly gleaming silver coins shimmering at the bottom of a wishing well and hence the name. First recorded in 1752 by Nicolas Lacaille, NGC 3532 contains around 120 stars superimposed on the expanse of the Milkyway and is visible with the naked eye from lower latitudes. Links: https://500px.com/MikeODay http://photo.net/photos/MikeODay Details: Co-ordinates: ~ RA 11h 6.4m, Dec -58 deg 50.5' Skywatcher Quattro 10" f4 Newtonian Skywatcher AZ Eq6 GT Mount Orion Short Tube 80mm guide scope & auto guider - PHD2 Baader MPCC Mark 3 Coma Corrector Hutech IDAS D1 Light Pollution Filter Nikon D5300 (unmodified) Field of view (deg) ~ 1.35 x 0.90 36 subs ranging from 30 sec 300 sec ISO 200 Pixinsight & Photoshop 10th April 2016
  16. The Southern Beehive Cluster ( NGC 2516 ) in the constellation Carina re-processed ( improved colour balance, more colour in the smaller stars and lower saturation overall ): previous version: ( click on image to see larger ) Because of its similarity M44, NGC 2516, which is only visible from lower latitudes, has become known as the Southern Beehive Cluster. At a distance of around 1300 light years, NGC 2516 is relatively close to us and resides in the same spiral arm of the Milkyway as we do. Containing around 100 stars, with a number of them in the magnitude 5 to 6 range, NGC 2516 has an apparent magnitude of 3.8 and is visible to the naked eye as a small bright hazy patch at the edge of the Milkyway. Details: RA 7h 58.4m, Dec -60 deg 41.9' Skywatcher Quattro 10" f4 Newtonian telescope Skywatcher AZ Eq6 GT Mount. Guiding: Orion Shortube 80 guidescope, Starshoot Autoguider, PHD2, guiding RA only Baader MPCC Mark 3 Coma Corrector. Hutech IDAS D1 light pollution filter Nikon D5300 (unmodified) Long exposure noise reduction on Stack of 14 x 360sec images @ ISO400 Pixinsight
  17. Also known as the Theta Carinae Cluster, The Southen Pleiades is a very bright open cluster in the Carina constellation. It was discovered by Abbe Lacaille during his visit to South Africa in 1752. Containing around 60 stars, IC 2602 shines with an overall magnitude of 1.9 and its brightest member is Theta Carinae with a visual magnitude of 2.7. This cluster of young blue stars is relatively close to us at "only" 479 light years. 5 May 2018 The Southern Pleiades open star cluster ( IC 2602 ) in Carina ( please click / tap on image to see larger and sharper ) Image details can be found here.
  18. From the album: Wide-Angle Shots

    First of all, sorry about the crane Don't get confused about the red light on top of it XD I was confused when i first looked at the image! Here you can see the Orion Constellation, and the Pleiades Cluster to the right of the image. Now that's over and done with, I am not sure of how long the exposure was, but i'm guessing 10-20 seconds of exposure, definitely f/2.8, i'm gonna guess the ISO Speed was ISO 200-400, not too sure on the focal length, though. I reckon this image was taken around early 2017, considering i was at one of my friend's house at the time, and he moved out of there around March/April time. Hope you like the picture
  19. The Great Barred Spiral Galaxy ( NGC 1365 ) in the constellation Fornax edit: new version with new long exposure data ( 52 x 240sec ) and better dark subtraction / dithering to remove streaks in the noise and amp glow. This also allowed for a greater stretch revealing more faint data in the galaxy and small faint fuzzies in the image .. The Great Barred Spiral Galaxy ( NGC 1365 ) in Fornax ( please click / tap to see larger ) and below I have added a 100% crop of new version: ........ original image: NGC 1365 ( please click / tap on image to see larger ) ............... The Great Barred Spiral Galaxy ( NGC 1365 ) in the Constellation Fornax Below the equator, not seen from much of the Northern hemisphere, NGC 1365 passes very nearly directly overhead an observer situated near Cape Town, as Sir John Herschel was in November of 1837, or near Sydney, as I was, almost exactly 180 years later, when I photographed this “remarkable nebula” that is numbered 2552 in his book of observations from the Cape. Not called a “nebula” now, of course, this striking object is one of the nearest and most studied examples of a barred spiral ( SB ) galaxy that also has an active galactic nuclei resulting in its designation as a Seyfert galaxy. At around 60 M light years from Earth, NGC 1365 is still seen to occupy a relatively large area ( 12 by 6 arc minutes ) due to its great size; at some 200,000 light years or so across, NGC 1365 is nearly twice as wide as the Milky Way and considerably wider than both the Sculptor and Andromeda galaxies. This High Dynamic Range ( HDR ) image is built up from multiple exposures ranging from 4 to 120 seconds with the aim of capturing the faint detail in the spiral arms of the galaxy whilst also retaining colour in the brightest star ( the orange-red 7th magnitude giant, HD 22425 ). Also, scattered throughout the image, and somewhat more difficult to see, are numerous and far more distant galaxies with apparent magnitudes of 16 to 18 or greater. Mike O'Day ................. Identification: The Great Barred Spiral Galaxy New General Catalogue - NGC 1365 General Catalogue - GC 731 John Herschel ( Cape of Good Hope ) # 2552 - Nov 28, 29 1837 Principal Galaxy Catlogue - PCG 13179 ESO 358-17 IRAS 03317-3618 RA (2000.0) 3h 33m 37.2 s DEC (2000.0) -36 deg 8' 36.5" 10th magnitude Seyfert-type galaxy in the Fornaux cluster of galaxies 200 Kly diameter 60 Mly distance .................. Capture Details: Telescope: Orion Optics CT12 Newtonian ( mirror 300mm, fl 1200mm, f4 ). Corrector: ASA 2" Coma Corrector Quattro 1.175x. Effective Focal Length / Aperture : 1400mm f4.7 Mount: Skywatcher EQ Guiding: TSOAG9 Off-Axis-Guider, Starlight Xpress Lodestar X2, PHD2 Camera: Nikon D7500 (unmodified) (sensor 23.5 x 15.7mm, 5568x3712 @ 4.196um pixels) Location: Blue Mountains, Australia Moderate light pollution ( pale green zone on darksitefinder.com map ) Capture ( 22 Nov 2017 ) 6 sets of sub-images with exposure duration for each set doubling ( 4s to 120s ) all at ISO400. 70 x 120s + 5 each @ 4s to 60s total around 2.5hrs Processing ( Pixinsight ) Calibration: master bias, master flat and no darks Integration in 6 sets HDR combination Image - Plate Solution ========================================== Resolution ........ 1.328 arcsec/px Rotation .......... -0.008 deg ( North is up ) Field of view ..... 58' 8.6" x 38' 47.5" Image center ...... RA: 03 33 41.182 Dec: -36 07 46.71 ==========================================
  20. A sky full of stars in this 6 pane mosaic taken from Galloway Starcamp at Drumroamin Farm Campsite near Kirkinner on the Solway coast, bitterly cold with very strong winds blowing. www.drumroamin.co.uk/ In this image planet Jupiter rises in the east within the zodiacal constellation Leo ahead of the back-to-front question mark asterism that is the sickle of Leo. Cars on the A75 in the distance across the bay leave a trail of broken yellow lights along the coast road in this long exposure image while low cloud shrouds the summit of Cairnharrow. Canon 60Da Nikon 50mm AIS lens at f5.6 Exp 300secs per 6 panes of this mosaic iso 1600 PT Lens & PSCS6 18th/19th November 2014 A Sky Full of Stars - Galloway Starcamp by mikeyscope, on Flickr
  21. The constellations, they can be filled with beautiful objects for us to observe.Popular constellations such as Orion, Monoceros, Canis Major and Puppis all host beautiful nebulae and star clusters along with gorgeous binary and variable stars. Every constellation has it's charm, but some just don't get the spotlight. I'm talking about the underrated constellations. These include Equuleus, Canes Venatici, Leo Minor, Sagitta, Vulpecula and Lynx. But my personal favorite, Delphinus the dolphin. When I looked at DK's " Astronomy " book ( Fantastic book and guide for beginners I highly recommend ) In the constellation section where it gives a detailed description and the history of the constellation it also notes some objects of interest too. Delphinus only had one, Gamma Delphini which is a great golden binary with an 8.9 arcsecond separation in the nose of the dolphin. But this of course isn't the only object of interest in Delphinus, I have been exploring it the last few evening in my telescope and binoculars and I found some very interesting things. Enjoy Our first object other than Gamma Delphini is a nice open star cluster with no name I came across myself, it is composed of 6th and 7th magnitude stars the brightest being Omicron Dephini at magnitude +5.85. To locate it, find Rotanev ( Beta Delphini ) and find Deneb Dulfim ( Epsilon Delphini ) draw a small line line to the left of Rotanev. Then draw a line vertically from Deneb Dulfim, the point where these to lines meet is very close to the location of the star cluster. Next we have NGC 7006 and Caldwell 47. Two very nice globular clusters for large telescopes. Have you ever looked at Delphinus through 7x50 binoculars? The entire constellation fits in the optics, meaning you can have a look at all the stars that make up this beautiful constellation! It looks alot like a big open star cluster! That is my list of objects I discovered through my adventure in Delphinus, my favorite underrated constellation. Please tell me yours and some of the objects in it! Thanks Adam
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