Search the Community
Showing results for tags 'jewel box'.
Found 6 results
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.
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
14-15 May 2015Equpiment: NexStar 8SE On the night of 14/15 May as I continued to image Lamda Centauri nebula through the Sulfur single Ion filter through my refractor, I had to keep an eye out for passing clouds.. there were moments when thick clouds moved 15 or so minutes at a time over the patch of sky I was imaging, so I had to be near it to stop the exposure as the clouds rolled in then start it as they went away….Autoguiding of the running chicken nebula was done by OAG and Celestron NexGuide. So I thought, one thing I haven’t done in way too long was do some nice old fashioned eyepiece observing…. I set up the SCT on the Alt-Az mount I’ll tell you I had some awesome views… AWESOME…. First I looked at Saturn…. It was bright and massive at 406X magnified… clearly visible was the Cassini division in the rings, the cloud belts and ring shadow on the globe and 6 of its moons around it…. then after about 30 or 40 minutes of absorbing that view I moved onto the Omega Centauri… first with the low power 50X magnified… the globular cluster was clear, and a clear fuzzball of stars in the eyepiece circle…. Then I tried the TV11mm Nagler I recently received. The view in high power… what I saw has to be seen to be believed, at 185X not only was the globular massive and the individual stars were resolvable in the CORE!!!! The Core!!! But because the eyepiece is wide view the circle was not visible, it was almost out of the peripheral, so it was like looking into space through a window…. Awesome…. Then I went toward the Jewel Box near the southern cross… at low power the distinct “V” shape of the Jewel box was obvious and the different colors of the stars were visible. But with the high power eyepiece not only were the different colors of the stars visible and glistening but there were so many stars in the view that the “V” shape was almost lost, why it’s called the “Jewel Box” was plainly visible. Next target was the Carina nebul. Here I had to use the ultra high contrast filter to dim out the stars that overwhelm the nebula and I bs you not, with the filter there were actual whisps, folds and structures are visible within the nebula… stuff normally expected to need to be long exposed to see, but were visible through the eyepiece! Before those four I just described I looked at the Lagoon Nebula, the Trifid nebula and the butterfly nebula but those were too low into and toward lights from CBD so the details were washed out, I still saw the “lagoon” in the lagoon nebula but not as defined as it would be at a dark location or position in the sky. The Trifid and the butterfly were just a barely visible smudge. The butterfly had the shape of it visible but only barely. I remember when I took the scope to the mountains and looked at the Trifid nebula from there, the shape of the Trifid was clearly visible as well as the breaks in the “flower” part, tonight was not even close. I’ll tell you... it doesn’t seem like a lot of objects were looked at but more than 3 hours went by like nothing…. I didn’t feel that my bones have frozen through until I realized what time it was and that the object I was imaging moved behind the trees and buildings in the distance. In the last few years I mostly did astrophotography but after tonight I think I need to do more traveling to dark sites and do lot more observing. MG
This is a re-processed version of an old capture of mine taken last year when I was a two day old baby astrophotographer. Back then I was only just learing how to polar align my scope on its tripod and auto-guiding was a distant goal. This is a stack of 15 x 30sec images from my unmodified Nikon D300 ( I now use an unmodified D5300 as it is lighter and causes less flex in the focuser ). Description: The Jewel Box Cluster in the Crux Constellation ( NGC 4755 ) by Mike O'Day ( 500px.com/MikeODay ) Viewed through a telsecope, John Herschel described the Jewel Box Cluster as "a casket of varioulsy coloured precious stones" - hence the name. The Jewel Box, visible only from the Southern Hemisphere and appearing as a bright fuzzy star to the naked eye, is a cluster of around 100 ( mostly blue giant ) stars approximately 7000 light years from Earth. Links: 500px.com/MikeODay photo.net/photos/MikeODay Details: NGC 4755 - RA 12h 54.5m, Dec -60deg 26'. Skywatcher Quattro 10" f4 Newtonian. Skywatcher AZ Eq6 GT Mount. Unguided. Baader MPCC Mark 3 Coma Corrector. Nikon D300 (unmodified). Field of view (deg) ~ 1.35 x 0.90. Combination of 15 images 30 sec @ ISO800. Registax & Photoshop 24 April 2014 (re-processed Nov 2015)
Djt posted a topic in Imaging Challenge #12 - Open Clusters (Now Closed)Hi thought you might be interested in this. The Jewel box sits in Crux and is pretty spectacular in an eyepiece. This was captured using MaximDL and processed in PixInsight. Not much was done in terms of processing but as the stars are fairly young I boosted the blues a little as in its basic processed state they were pretty much white (so shorter subs needed?) location - Sydney gear GSO RC10a Truss (first light) Moravian G2 8300 with astronomiks filters AP900 mount Image data, RGB 24:24:24 in 3 minute subs Cheers
7th November 2015 Equipment: Olympus 10x50mm DPS-I on tripod (6 degree FOV) Time: 02:40-04:00 Orion's Sword: Orion Nebula was glowing quite brightly. There was hints of nebulosity around the Running Man and the stars very crisp points of light. Rosette central cluster was obvious, I thought I saw a very faint haze around it, but it was so dim that it was most likely wishful thinking. Pleiades very crisp and looked great. Through the crispness there was a very slight shimmer/twinkle to the stars. It was a great view, something that definitely needs the stability of a tripod to see. Jewel Box cluster was quite small but about 6 individual stars and a V shape was clearly visible. Alpha Cruxis was visible as double star. The bright primary was not resolvable as two. Cluster at the other side of Crux from the Jewel Box, easterly from the Carina Nebula there was a dense star field, definitely worth putting a camera on it to see if there is any nebulosity there. There was a distinct orange star among the star field, much brighter and orange than any of the other stars around. Initially I thought it looked out of place and reminded me of the supernova spotted in Sagittarius through the binoculars on 20 March 2015 @ 3:42am AEDT (16:42UT). The dense star field was approximately 1 degree in size so will most likely need to be imaged at 500mm f6.25 to get whole object into frame. Carina Nebula was nicely visible, the dark V shape dust lane... or A as it was orientated tonight, was clearly visible among shimmering stars and nebulous haze. As a note there was a star cluster in or near Canis Major to look into. The Olympus DPS-I 10x50mm binoculars are great, clear and sharp for astronomical observing, there is slight distortion to the extreme edges of the FOV but nothing that bothered me at all. It was a great night of binocular observing. MG