Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

sgl_imaging_challenge_banner_supernovae_remnants_winners.thumb.jpg.a13d54fa405efa94ed30e7abd590ee55.jpg

Search the Community

Showing results for tags 'ngc'.



More search options

  • Search By Tags

    Type tags separated by commas.
  • Search By Author

Content Type


Forums

  • Welcome
    • Welcome
  • Beginners
    • Getting Started General Help and Advice
    • Getting Started Equipment Help and Advice
    • Getting Started With Observing
    • Getting Started With Imaging
  • Community
    • Official SGL Announcements and Events
    • SGL Challenges and Competitions
    • SGL Star Parties
    • Star Parties & Astro Events
    • Celestial Events Heads Up
    • The Astro Lounge
  • Retailers
    • Sponsor Announcements and Offers
    • FLO Clearance Offers
    • Supplier Reviews
  • Astro Classifieds
    • For Sale / Swap
    • Wanted
  • Equipment
  • Observing
  • Video Astronomy
  • Imaging
  • Science
  • WADAS's WADAS Discussion Forum
  • Beaufort Club's Topics
  • Swindon Stargazers Club's Topics
  • East Midlands Stargazers''s Topics
  • Central Scotland Astro's Topics
  • SGL Cumbrian Skies's Topics
  • Herts, Beds and Bucks Group's Topics
  • SGL East Anglian Group's Topics
  • South Leicester Observers's Topics
  • South Wales Group's Topics
  • SGL Surrey Observers's Topics
  • South Yorkshire Stargazers's Topics
  • Yorkshire Astronomers's Topics
  • Devon and Cornwall's Topics
  • West Midlands's Topics
  • Essex Cloud Dodgers's Topics
  • Essex Cloud Dodgers's New equipment
  • NLO and Planetarium's Topics
  • Astronomical Society of Edinburgh's Discussion
  • Leicester Astronomical Society's Topics
  • Dorset Stargazers's Topics
  • Hairy Stars Club (Comets)'s Tutorials and Guides
  • Hairy Stars Club (Comets)'s General Discussion
  • Hairy Stars Club (Comets)'s Observing Campaigns
  • Hairy Stars Club (Comets)'s Analysis results
  • Hairy Stars Club (Comets)'s Useful Links
  • Pixinsight Users Club's Pixinsight Discussion Forum

Calendars

  • Astro TV
  • Celestial Events
  • SGL Calendar
  • Astro Society Events
  • Star Parties
  • WADAS's Events
  • Beaufort Club's Events
  • Astronomical Society of Edinburgh's Events
  • Leicester Astronomical Society's Events
  • Dorset Stargazers's Events

Blogs

There are no results to display.

There are no results to display.


Find results in...

Find results that contain...


Date Created

  • Start

    End


Last Updated

  • Start

    End


Filter by number of...

Joined

  • Start

    End


Group


AIM


MSN


Website URL


ICQ


Yahoo


Jabber


Skype


Interests


Location

Found 87 results

  1. Update: 3rd June Re-processed to remove slight magenta tint caused by the non-uniform removal of light pollution by the DBE process ( it was being fooled by the very bright image centre ). The globular star cluster Omega Centauri ( NGC 5139 ) in Centaurus ( please click / tap on image to see larger and sharper ) A full size image can be found here. original below ..... A newly captured ( May 2018 ) image of the great southern globular star cluster, Omega Centauri ( NGC 5139 ) Omega Centauri ( NGC 5139 ) in Centaurus - ( please click / tap image to see larger and sharper ) A full size ( ~ 6000 x 4000 ) image can be found here ....... This image is an attempt to look deeply into the mighty Omega Centauri star cluster and, by using HDR techniques, record as many of its faint members as possible whilst capturing and bringing out the colours of the stars, including in the core. Image details: Resolution ........ 0.586 arcsec/px ( full size image ) Rotation .......... 0.00 deg ( up is North ) Focal ............. 1375.99 mm Pixel size ........ 3.91 um Field of view ..... 58' 20.9" x 38' 55.1" Image center ...... RA: 13 26 45.065 Dec: -47 28 27.26 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 3.9um pixels)\ Location: Blue Mountains, Australia Moderate light pollution ( pale green zone on darksitefinder.com map ) Capture ( May 2018 ) 8 sets of sub-images with exposure duration for each set doubling ( 2s to 240s ) all at ISO 250. Processing: Calibration: master bias, master flat and master dark Integration in 8 sets HDR combination Pixinsight May 2018
  2. The Great Barred Spiral Galaxy ( NGC 1365 ) in the Constellation Fornax ………………………. ( edit - star chart added ) The Great Barred Spiral Galaxy ( NGC 1365 ) - Chart ( please click/tap on image see larger and sharper version ) A full size ( 6200 x 4407px ) image can be downloaded from here. ………………………. Details: 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 when he discovered 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 240 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. ................. 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 : 1375mm 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 ( 3, 7 & 8 Dec 2018 ) 7 sets of sub-images with exposure duration for each set doubling ( 4s to 240s ) all at unity gain ( ISO 250). 140 x 240s + 10 each @ 4s to 120s total around 9.7 hrs Processing ( Pixinsight ) Calibration: master bias, master flat , master dark Integration in 7 sets HDR combination Links: 500px.com/MikeODay photo.net/photos/MikeODay <a href="http://www.flickr.com/photos/mike-oday">www.flickr.com/photos/mike-oday</a> Image Plate Solution =================================== Resolution ........ 0.586 arcsec/px ( full size image ) Rotation .......... -0.003 deg ( North is up ) Field of view ..... 58' 37" x 38' 55" Image center ...... RA: 03 33 36 Dec: -36 08 27 ===================================
  3. MikeODay

    Ptolomy's Cluster

    From the album: Mike's Images

    30 sec subs @ ISO 800 Guided Sykywatcher Quattro 10" f4 Newtonian Baader MPCC Mk3 Coma Corrector Skywatcher AZ EQ 6 GT Mount Orion auto guider on 80mm f5 guide scope Nikon D300 unmodified

    © Copyright Mike O'Day 2014 - all rights reserved

  4. From the album: Mike's Images

    Cat's Paw Nebula - NGC 6334 ( aka Bear Claw Nebula ) An emission nebula in Scorpius (near the scorpion's tail) RA 17h 25m 39.6s ; Dec -35deg 43' 48" . 7th August 2015. Skywatcher Quattro 10" f4 Newtonian. Skywatcher AZ Eq6 GT Mount Orion 80mm f5 guide scope and auto guider - PHD2. Baader MPCC Mark 3 Coma Corrector, UHC-S 'nebula' filter. Nikon D5300 (unmodified). Field of view (deg) ~ 1.35 x 0.90. ISO800, 14bit NEF, Long Exp. NR on. 28 x 200sec (starting at zenith) no moon, 3deg C, 70%RH, moderate LP. PixInsight

    © Copyright Mike O'Day 2015 - all rights reserved

  5. The Cat's Paw Nebula ( NGC 6334 ) in Scorpius updated ( slight tweak to colour balance, a little brighter and tad more contrast ) ( please click / tap on image to see larger and sharper - a full size image can be seen here ) ...... original: ( please click / tap on image to see larger and sharper - a full size image can be seen here ) ……………………... Also known as the Bear Claw Nebula, NGC 6334 is an emission nebula near the scorpion's tail in the Scorpius constellation. Image details: Image centre ...... RA: 17 20 08.185 Dec: -35 52 30.91 Field of view ..... 57' 37.8" x 38' 51.8" Rotation .......... 0.00 deg ( North is up ) Resolution ........ 0.586 arcsec/px 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 3.9um pixels) Location: Blue Mountains, Australia Moderate light pollution ( pale green zone on darksitefinder.com map ) Capture ( July 2018 ) 6 sets of sub-images with exposure duration for each set doubling ( 4s to 240s ) all at ISO 250. 168 x 4 min frames plus ~10 frames each for the shorter exposures Processing: Calibration: bias, dark and flat Integration in 8 sets HDR combination Pixinsight July 2018
  6. Bright Nebula NGC 6188 and open cluster NGC 6193 in Ara Magnitude +5.19, RA 16h 41m 42s, Dec -48deg 48' 46" Approx. 3800 light years away Skywatcher Quattro 10" f4 Newtonian. Skywatcher AZ Eq6 GT Mount (on concrete pier) Orion 80mm f5 guide scope and auto guider - PHD2. Baader MPCC Mark 3 Coma Corrector, UHC-S 'nebula' filter. Nikon D5300 (unmodified). Field of view (deg) ~ 1.35 x 0.90. UHC-S - 32 x 180 sec ISO800 (14bit NEF, Long Exp. NR on). Pixinsight and photoshop 7 July 15 (processed 29 August 15) Other images: photo.net/photos/MikeODay 500px.com/mikeoday
  7. From the album: Mike's Images

    Cat's Paw Nebula - NGC 6334 ( aka Bear Claw Nebula ) An emission nebula in Scorpius (near the scorpion's tail) RA 17h 25m 39.6s ; Dec -35deg 43' 48" . 7th August 2015. Skywatcher Quattro 10" f4 Newtonian. Skywatcher AZ Eq6 GT Mount Orion 80mm f5 guide scope and auto guider - PHD2. Baader MPCC Mark 3 Coma Corrector, UHC-S 'nebula' filter. Nikon D5300 (unmodified). Field of view (deg) ~ 1.35 x 0.90. ISO800, 14bit NEF, Long Exp. NR on. 28 x 200sec (starting at zenith) no moon, 3deg C, 70%RH, moderate LP. PixInsight

    © Copyright Mike O'Day 2015 - all rights reserved

  8. At the intersection of boredom, astronomy and excel lies my analysis of the objects within the NGC (sorry if this is old news). I made these tables using the data from the NGC/IC Project. It may help in further organizing your observational data, or planning, it might not, but it's kind of neat to see the breakdown by objects within the catalog (and it was fun to put together). Let me know if you catch any errors and I can update! -Rick Some interesting findings: I knew there were a bunch of galaxies in the NGC, just was not aware that 80% of all the existing, non-duplicate objects were galaxies There are more Double Stars in the NGC than Planetary Nebulae 7840 NGC entries, but only 5724 unique and existent objects (maybe 5723, depending on NGC 1990) 234 Entries are duplicates (or triplicates) The only duplicated entries are of galaxies There are 82 entries for which objects do not actually exist 83 is probably the real count if you say NGC 1990 does not exist January-April is a great time for open clusters June-August is a great time for globulars Any month is a great month for galaxies July and August are great for planetary nebulae 257 NGC objects are stars, doubles stars or triple stars Triples, Doubles and Single Stars are fairly evenly distributed across the catalog Total Objects in the catalog by Type: NGC Obect Type # of NGC Entries Duplicated Entries # of Unique NGC Objects % of Total % of Existing Objects Most Entries by Type within One NGC Range (Ex: 1-999 or 3000-3999) NGC Range with Most Objects by Type NGC Range with Second Most Count of the Second Most Entries by Type Gxy 6271 234 6037 79.4% 80.2% 890 4000-4999 5000-5999 875 OC 678 0 678 8.9% 9.0% 245 2000-2999 1000-1999 154 GC 142 0 142 1.9% 1.9% 73 6000-6999 1000-1999 30 Star 115 0 115 1.5% 1.5% 23 1-999 4000-4999 18 Neb 111 0 111 1.5% 1.5% 47 2000-2999 1000-1999 31 Double Star 106 0 106 1.4% 1.4% 17 6000-6999 1-999 13 PN 98 0 98 1.3% 1.3% 49 6000-6999 2000-2999 14 OC+Neb 89 0 89 1.2% 1.2% 44 1000-1999 2000-2999 17 Ast 69 0 69 0.9% 0.9% 19 6000-6999 2000-2999 18 Triple Star 36 0 36 0.5% 0.5% 9 2000-2999 1-999 3 GxyCld 22 0 22 0.3% 0.3% 11 5000-5999 1-999 0 MWSC 8 0 8 0.1% 0.1% 8 6000-6999 N/A 0 SNR 6 0 6 0.1% 0.1% 5 6000-6999 1000-1999 1 HIIRgn 6 0 6 0.1% 0.1% 3 4000-4999 3000-3999 2 Neb?* 1 0 1 0.0% 0.0% 1 1000-1999 N/A 0 Nonexistent 82 0 0 1.1% ---- 19 1000-1999 7000-7840 17 Total 7840 234 7524 Neb? *refers to NGC 1990 Objects by Type and Position within the Catalog: NGC Number Galaxy Galaxy Cloud Nebula Questionable Nebula Open Cluster and Nebula Open Cluster Globular Cluster Planetary Nebula Super Nova Remant HII Region Milky Way Star Cloud Triple Star Double Star Star Asterism Nonexistent 1-999 834 6 4 0 12 49 8 4 0 0 0 6 16 23 5 8 1000-1999 646 0 31 1 44 154 30 4 1 0 0 3 13 13 10 19 2000-2999 596 4 47 0 17 245 5 14 0 1 0 9 12 17 18 8 3000-3999 873 1 8 0 2 21 1 7 0 2 0 3 15 10 0 7 4000-4999 890 0 0 0 0 12 5 2 0 3 0 2 5 18 3 7 5000-5999 875 11 1 0 0 28 15 7 0 0 0 2 14 11 2 5 6000-6999 634 0 15 0 12 120 73 49 5 0 8 6 17 6 19 11 7000-7840 689 0 5 0 2 49 5 11 0 0 0 5 14 17 12 17 Total 6037 22 111 1 89 678 142 98 6 6 8 36 106 115 69 82
  9. The Lagoon Nebula ( Messier 8, NGC 6523 ) in the constellation Sagittarious. ( click on image to see larger) The Laboon Nebula ( M8 ) is visible to the naked eye under dark skies from most latitudes except the far north. Seemingly covering an area about three times that of the full Moon, M8 actually covers an area somewhat greater than 110 light years and is around 4300 light years from Earth in the Sagittarius-Carina spiral arm of the Milkyway galaxy. ...... The frames for this image where taken back when I was very new to astrophotography and I was experimenting with camera settings. On this occasion I wanted to see if JPEG images might be easier to process - I was disappointed with the results. Now that I have a bit more knowledge and skill at processing I decided to have another attempt at trying to process the set because I liked the way the JPEG files had retained colour in the stars. I am reasonably pleased with the result; the faint detail in the nebula is not there but I quite like the colours in the centre and in the stars. Details: Messier 8, NGC 6523 - Lagoon Nebula Skywatcher Quattro 10" f4 Newtonian telescope. Skywatcher AZ Eq6 GT Mount.Orion auto guider - PHD2. Baader MPCC Mark 3 Coma Corrector. Nikon D300 (unmodified). 80 x 30 sec ISO 1600 (JPEG) - 31 Aug 14. PixInsight and Photoshop. processed 13 August 2016 Links: https://500px.com/MikeODay http://photo.net/photos/MikeODay
  10. The Eagle Nebula Messier 16 ansd Open Cluster NGC 6611 in the constellation Serpens. ( click on image to see larger ) M16 is around 7,000 light years distant from Earth in the Sagittarius-Carina spiral arm of our Milkyway galaxy and may be part of a larger structure that extends to and includes the Omega Nebula ( M17 ) in Sagittarius. Details: Eagle Nebula - Messier 16 ( IC 4703 ), Open Clusters - NGC 6611 and Trumpler 32. RA ~ 18h 19'm45s Dec ~ -13deg 46' 20" 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, UHC-S 'nebula' filter. Nikon D5300 (unmodified). Field of view (deg) ~ 1.35 x 0.90. ISO800, 14bit NEF, Long Exp. NR on. 35 x 180sec (1/3 before & 2/3 after zenith) 17 July 2015. PixInsight re-processed 21 Aug 2016.. Links: https://500px.com/MikeODay http://photo.net/photos/MikeODay
  11. Galaxy NGC 4945 in Centaurus Details: Galaxy NGC 4945 in Centaurus 19 May 2018 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 .......... North is up Focal ............. 1375.43 mm Pixel size ........ 3.91 um Field of view ..... 43' 27.2" x 28' 54.2" Image center ...... RA: 13 04 51.790 Dec: -49 30 37.17 ========== Location: Blue Mountains, Australia Moderate light pollution ( pale green zone on darksitefinder.com map ) Capture ( 19 May 2018 ): 10 sets of sub-images with exposure duration for each set doubling ( 1/2th sec to 240 sec ) all at ISO250. ( 41 x 240sec + ~8 each forthe other durations ) Processing: Calibration: master bias, master flat and master dark Integration in 10 sets HDR combination Pixinsight May 2018
  12. Update 16th June: I could not wait to tell people that I was just notified that my image of Omega Centauri will be published as a future NASA's Astronomy Picture of the Day ( APOD ) - my first ever I will update the thread when they publish. ................................. A deep look at Omega Centauri ( NGC 5139 ) This image is an attempt to look deeply into the the Omega Centauri globular cluster by using HDR techniques to record as many faint stars as I can whilst retaining colour and detail in the bright stars, including at the core ... ............. Reprocessed to bring out more faint stars and to produce a smother transition between brightness levels. New version ( 12 June 2017 ): Omega Centauri ( NGC 5129 ) ( please click / tap on image to see lager and sharper ) .......... Old version: Omega Centauri ( NGC 5129 ) ( please click / tap on image to see full size and sharper ) Image details: from www.nova.astrometry.net: Size: 58.6 x 39 arcmins, Centre: 13h 26 min 50.4 sec, -47deg 28' 39.1''. Orientation: up is -89.9 East of North ( ie. E^ 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). No filter Long Exposure noise reduction off Location:. Blue Mountains, Australia. Moderate light pollution ( pale green zone on darksitefinder.com map ). Capture: 9 sets of sub-images with exposure duration for each set doubling ( 1s to 240s ) all at ISO800. Processing:. Calibration: master bias, master flat and no darks. Integration in 9 sets. HDR combination. Pixinsight May 2017
  13. Carina Nebula with the bright unstable star Eta Carinae in the centre of the image. edit ( 27 March ): Tweak to shadow levels to bring out more detail and also a slight reduction in the brightness of the highlights. A much larger version ( 4562 x 3072 6062 x 4082) is available on my Flickr page. previous version: Carinae Nebula ( NGC 3372 ) ( please click / tap on image to see larger and sharper ) From Wikipedia ... "Eta Carinae is a highly luminous hypergiant star. Estimates of its mass range from 100 to 150 times the mass of the Sun, and its luminosity is about four million times that of the Sun." This HDR image is constructed from 12 sets of exposures ranging from 1/8 sec ( to capture the bright centre of Eta Carinae ) through to 240 seconds. Total exposure time around 13 hours 17-19 March 2018 Image details: Objects in image: Hypergiant, Eta Carinae ( HD 93308 ) in the centre of the Homunculus Nebula Carina Nebula ( NGC 3372 ) Keyhole Nebula Open Star Clusters: - Trumpler 14, 15, 16 - Collinder 232 Field of view ..... 59' 18.2" x 39' 56.0" Image centre ...... RA: 10 45 01.762 Dec: -59 40 52.87 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 3.9um pixels) Location: Blue Mountains, Australia Moderate light pollution ( pale green zone on darksitefinder.com map ) Capture ( 17, 18 & 19 March 2018 ): 12 sets of sub-images with exposure duration for each set doubling ( 1/8s to 240s ) all at ISO250. ( 181 x 240sec + 10 to 20 each for the other durations ) Processing: Calibration: master bias, master flat and master dark Integration in 12 sets HDR combination Pixinsight March 2018
  14. The Discovery of the Sculptor Galaxy by Miss Caroline Herschel in 1783 On the 23rd of September 1783, sitting before her telescope in the field behind the house she shared with her brother William in Datchet near Slough in the south of England, Miss Caroline Herschel "swept" the sky searching for new comets and never before seen star clusters and nebulae. On this occasion, way down in the sky, not far above the Southern horizon, Miss Herschel saw and noted down a very bright and large nebula where one had never before been recorded and that was later recognised by her brother, Sir William, as the discovery by Caroline Herschel of the nebula he listed in his catalogue as H V.1. ( circ. 1825-33, Sir John Herschel, beloved nephew of Miss Caroline Herschel ) Today we know this 'nebula' to be, not as some thought then, a swirling mass of stars and gases within our own galaxy, but rather, a galaxy not unlike our own but way more distant than the outer reaches of of own Milkyway galaxy. Given various names, Silver Dollar Galaxy, Sliver Coin Galaxy or simply by its number in the New General Catalogue, NGC 253, it is most commonly called the Sculptor Galaxy and we owe its discovery to the first female professional astronomer. Caroline Herschel ( 1750 - 1848 ) ... ( link ) ( 1782 - 1783 ) ... ... ... H V.1 Observed ( by WH ): 30 Oct 1784 128 minutes, 17 seconds following and 1 degree, 39 minutes north of referenced star Description: - cB: "confidently bright" - mE: "much extended: - sp: "south preceding" - nf: "north following" -mbF: "much brighter middle" - size: 50' x 7 or 8' from: ( link ) ............................... The location reference to H V.1 ( NGC 253 ) in William Hershel's catalogue is in relation to a star found in Flamsteed's Catalogue, 18 Pis. Aust., which is #18 in Piscis Austrainus or Epsilon PsA, the 4th magnitude star HD214748 ( HIP111954 ) ( source ) ( Plate from "Atlas Coelestis" by John Flamsteed, 1646-1719 ) ------------------------------------- William Herschel found favour with the King and was granted a position as Royal Astronomer to George III in 1782. Shortly after, William and Caroline moved from Bath to Datchet ( near Windsor ) and took up residency in a rented house which, whilst somewhat delapadated and damp, had ample accommodation and fields for William to construct and deploy the large telescopes he wished to build. It was in these grounds that Caroline set up her "Sweeper" to look for comets and doing so also discovered a number of 'nebulae' including ( in 1783 ) what was later to become known as the Sculptor Galaxy. ( The Herschel house at Datchet near Windsor ) ( The Lawn, Horton Road, Slough ( Datchet ) - Google Maps ) ............. Caroline Herschel's "Sweeper" was a 27" focal length Newtonian telescope that was supported in a kind of altitude-azimuth mount consisting of a rotating table and a small gantry and pulley system that was used to effect altitude adjustments by sliding the tube up and down against a board used to provide stability. There has been some conjecture as to the exact details of the construction, however the image below, even if perhaps not the actual instrument, gives an indication of the overal design philosophy. Late in her life Caroline Herschel recorded details of her telescope in a booklet titled "My little Newtonian sweeper": In her memoir, Caroline Herschel describes the performance of her observations as the conducting of "horizontal sweeps"; from which one might assume the task consisted of setting the altitude in accordance with the plan for the night's observing and then slowing rotating the top of the table in azimuth as one observed and noted down the objects that passed across the view in the eyepiece. However, with the arrival of this new "telescopic sweeper" in the middle of 1783, Caroline Herschel added the new method of sweeping in the vertical, as noted below in an extract from her observing book ( source for both extracts: "Caroline Herschel as observer", Michael Hoskin, Journal for the History of Astronomy, 2005 ) .... The achievement of her discovery of the 'nebula' in the Sculptor constellation was remarkable in so many ways; not the least of which being the low path in the sky that the Sculptor galaxy follows when observed from Datchet in southern England - which on the night of her observation would not have exceeded 12 degrees or so above the horizon. Today, 234 years later, and blessed with 21st century luxuries and conveniences, I write on my IPAD and flip over to my planetarium application, SkySafari, and model the sky as it was seen by Caroline Herschel from near her house on the 23rd of September, 1783 ... ( SkySafari by Simulation Curriculum )
  15. Barred 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 30 million years ago. Details: Spiral Galaxy NGC 6744 in Pavo. 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. ISO800, 14bit NEF, Long Exp. NR on. 44 x 120sec 4th Sept 2016 Processed in PixInsight and finished off in Photoshop. Links: https://500px.com/MikeODay http://photo.net/photos/MikeODay
  16. From the album: Mike's Images

    The Lagoon Nebula ( Messier 8, NGC 6523 ) in the constellation Sagittarius - by Mike O'Day ( https://500px.com/mikeoday ) The Laboon Nebula ( M8 ) is visible to the naked eye under dark skies from most latitudes except the far north. Seemingly covering an area about three times that of the full Moon, M8 actually covers an area somewhat greater than 110 light years and is around 4300 light years from Earth in the Sagittarius-Carina spiral arm of the Milkyway galaxy. Links: https://500px.com/MikeODay http://photo.net/photos/MikeODay Details: Messier 8, NGC 6523 - Lagoon Nebula. also contains: NGC 6526 NGC 6530 NGC 6533 IC 1271 IC 4678 7SGR 9SGR Skywatcher Quattro 10" f4 Newtonian telescope. Skywatcher AZ Eq6 GT Mount. Orion auto guider - PHD2. Baader MPCC Mark 3 Coma Corrector, UHC-S 'nebula' filter. Nikon D300 (unmodified) (14bit NEF). Field of view (deg) ~ 1.35 x 0.90. 20 x 120 sec ISO400. 26 x 30 sec ISO 1600. 23 x 240 sec ISO 200. PixInsight and Photoshop. 2 August 14 . re-processed 24 April 2016 to include the additional subs ( the first version only made use of the 23 x 240 sec ISO 200 subs ) and putting use the processing lessons I have learnt over the past year.

    © Copyright Mike O'Day 2016 - all rights reserved

  17. 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
  18. 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 ...
  19. Aenima

    double cluster 2

    From the album: The next step.

    One of my first targets but still trying to get a decent image - clusters are harder than they look to capture due to them being all stars so tracking errors and uncorrected optical problems are very quick to show up in the end result.

    © Aenima

  20. My first attempt at processing the subs I took last night. Not totally happy yet - next time I process it I think I need to boost the red in the mid tones somewhat to try to compensate for the filter in my standard Nikon D5300. Details: Rosette Nebula in Monoceros ( NGC 2237, 2238, 2239, 2244, 2246 ) by Mike O'Day ( 500px.com/MikeODay ). The Rosette Nebula surrounds a cluster of bright young stars (NGC 2244) and is around 5,200 light years from Earth. Links: https://500px.com/MikeODay http://photo.net/photos/MikeODay This image ~ RA 6h 31m, Dec 5deg 2'. 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 (no filter used). Nikon D5300 (unmodified). Field of view (deg) ~ 1.35 x 0.90..71 x 30 sec ISO 800. Pixinsight & Photoshop. 20 December 2015
  21. A deep look at Omega Centauri ( NGC 5139 ) edit: re-processed from the original exposures - April 2018 ........ previous version: Omega Centauri ( please click / tap on image to see larger and much sharper ) This image is an attempt to look deeply into the mighty Omega Centauri star cluster and, by using HDR techniques, record as many of its faint members as possible whilst capturing and bringing out the subtle colours of the stars, including in the core. ( re-processed from May 2017 subs - master dark added to workflow, new HDR / colour process workflow and stretched using ArcSinh ) Image details: Field of view ..... 58' 32.3" x 38' 55.6" Image center ...... RA: 13 26 50.290 Dec: -47 28 39.80 Orientation: East is up, North is to the right 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 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) Location: Blue Mountains, Australia Moderate light pollution ( pale green zone on darksitefinder.com map ) Capture ( May 2017 ): 9 sets of sub-images with exposure duration for each set doubling ( 1s to 240s ) all at ISO800. Processing: Calibration: master bias, master flat and master dark Integration in 9 sets HDR combination ArcSinh stretch Pixinsight March 2018 Links: 500px.com/MikeODay photo.net/photos/MikeODay www.flickr.com/photos/mike-oday
  22. Re-processed to try to bring increase the brightness of the various nebulae and increase the contrast a little without futher blowing out the stars and adding too much noise ... orignial: Orion's Belt - centred on "Alnitak", is a 1.7 magnitude triple star 740 light years from Earth and appears at one end of the belt. The Flame nebula ( cat: NGC 2024 or Sharpless 2-277 ) ( lower centre left of the image) glows yellow-pink due to the ionising radiation that comes from Alnitak. Seen from Earth, the Flame nebula is behind Alnitak and around 80 light years further away from Earth. The Horsehead nebula ( cat: Barnard 33 ) ( centre right of the image ) is a dark dust and gas cloud that is only visible from Earth due to the backlight illumination and silhouetting caused by the bright pink glow from the ionised hydrogen gas in the emission nebula IC 434. The bright blue reflection nebula below and to the left of the Horsehead is NGC 2023. Details: Combination of two sessions over a year apart. Skywatcher Quattro 10" f4 Newtonian. 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). 14bit NEF, Long Exp. NR on. 18 Dec 2015. 21 x 20 sec ISO 800. 165 x 30 sec ISO 800. 13 x 60 sec ISO 800 . Baader UHC-S , 12bit NEF, Long Exp. NR on. 5 Oct 2014. 19 x 2min ISO400 Pixinsight Links:. https://500px.com/mikeoday http://photo.net/photos/MikeODay
  23. From the album: CCD venture

    A h-alpha shot of the Wizard nebula in Cepheus. ED80 - ATK16HR - Ha clip filter - EQ6 - finderguider 9x50mm PhD2 - photoshop - DSS.
  24. From the album: Mike's Images

    Bright Nebula NGC 6188 and open cluster NGC 6193 in Ara by Mike O'Day Magnitude +5.19, RA 16h 41m 42s, Dec -48deg 48' 46" Approx. 3800 light years away Skywatcher Quattro 10" f4 Newtonian. Skywatcher AZ Eq6 GT Mount (on concrete pier) Orion 80mm f5 guide scope and auto guider - PHD2. Baader MPCC Mark 3 Coma Corrector, UHC-S 'nebula' filter. Nikon D5300 (unmodified). Field of view (deg) ~ 1.35 x 0.90. UHC-S - 32 x 180 sec ISO800 (14bit NEF, Long Exp. NR on). Pixinsight and photoshop 7 July 15 (processed 29 August 15) source: photo.net/photos/MikeODay 500px.com/mikeoday

    © Copyright Mike O'Day 2015 - all rights reserved

  25. 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
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.