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As promised, a second upload of the Virgo Cluster, this time with labels attached to some of the brighter galaxies. Blowing up the original image can reveal more that I haven't labelled yet.
This image is M4, the large and conspicuous Globular Cluster in Scorpio, just west of Antares. This image is a stack of 6 240-sec exposures with the 60mm Astro-Tech and the Nikon D5100, with a 2x tele-extender, at ISO 800, taken at the Blair Valley Observing Site, April 22, 2012.
M4 was discovered by Philippe Loys de Chéseaux in 1746.
Messier 4 (M4, NGC 6121) is one of the nearest globular clusters in the sky at an estimated distance of about 7,200 light years. Situated prominently about 1.3 degrees west of Antares, in constellation Scorpius, and being as bright as mag 5.6 visually, it can be detected by the naked eye under very dark skies, and is prominent with the slightest optical aid.
Globular cluster M4 was discovered by De Chéseaux in 1745-46 and listed by him as No. 19, and included in Lacaille's catalog as Lacaille I.9. Charles Messier cataloged it on May 8, 1764 and was the first to resolve it into a "cluster of very small [faint] stars;" this is the only globular cluster he could resolve with his moderate instruments, and thus the first globular cluster ever to be resolved. Only about 20 years later, William Herschel was able to resolve all Messier globulars with his large telescopes.
According to newer results (here adopted from W.E. Harris' database), the distance of M4 is perhaps only about 7,200 light years, which until recently, has perhaps been the smallest for a globular; the only serious competitor was NGC 6397 in the southern constellation Ara, yet that one seems to be very slightly more remote now (7,500 light-years). This changed only with the recent (2007) discovery of faint globular cluster FSR 1767 (or 2MASS-GC04) which is estimated at only 4,900 light-years.
As a remarkable detail, M4 displays a central "bar" structure, visible in our photo, roughly from slightly below left to slightly above right; this bar of 11th mag stars is about 2 1/2 ' long in position angle 12 deg and was first noted by William Herschel in 1783. It may be that this structure caused Harlow Shapley to consider it to be elongated slightly elliptically (0.9, in position angle 115 deg), a notion which cannot be confirmed in modern observations or photographs.
M4 would be one of the most splendid globulars in the sky if it were not obscured by heavy clouds of dark interstellar matter. Interstellar absorption also reddens the color of the light from the cluster, and gives it a slightly orange or brown-ish appearance on color images. Its angular diameter, seen on deep photographs, is about 36 minutes of arc, more than that of the Full Moon; this corresponds to a linear diameter of about 75 light years. On typical photos it appears somewhat smaller at about 26', and visually it was estiamted at 14 arc minutes. Its tidal radius, determined by the distance where tidal gravitational forces of the Milky Way Galaxy would cause member stars to escape, is estimated at 32.49', or about 70 light-years, so that this globular gravitationally dominates a spherical volume 140 light-years in diameter.
M4 is one of the most open, or loose, globulars, as its classification in concentration class IX indicates. Its compressed central core was measured at 1.66' diameter, or linearly 3.6 light-years. Its half-mass radius is 3.65' or about 8 light-years, so half the cluster's mass is concentrated in an inner spherical volume of 16 light-years diameter. It is receding from us at 70.4 km/sec and contains at least 43 known variables. Its spectral type has been determined as F8, its color index has been measured at B-V=1.03.
In 1987, the first millisecond pulsar was discovered in this globular cluster. This pulsar, 1821-24, is a neutron star rotating (and pulsating) once every 3.0 milliseconds, or over 300 times per second, which is even 10 times faster than the Crab pulsar in M1. A second millisecond pulsar was found in M28 later in the same year.
In August 1995, the Hubble Space Telescope has photographed white dwarf stars in M4, which are among the oldest stars in our Milky Way Galaxy. In July 2003, investigations with the Hubble Space Telescope led to the identification of a planet orbiting one of these white dwarfs; they form a triple system with a pulsar called PSR B1620-26. This planet, of a mass 2.5 times that of Jupiter, is presumably about as old as the globular cluster M4, a figure currently estimated at about 13 billion years, or almost three times the age of our solar system.
M4 can be easily found as it is only 1.3 deg west of bright Antares (Alpha Scorpii, mag 1.0, spectral type M 1.5 I, slightly variable), just south of the line to Sigma Scorpii (mag 2.9v, spec B2 III). A round diffuse patch in binoculars, it is a circular glow in small telescope, and even a 4-inch resolves the brightest stars, which are of about mag 10.8; the bar feature mentioned above is evident, and the reseolved stars appear irregularly distributed. Larger telescopes show a halo of stars around the bright central portion of the cluster to a diameter of over 16 arc minutes.
cluster of apples - Close photo of a group of apples.. To Download this image without watermarks for Free, visit: www.sourcepics.com/free-stock-photography/24712740-cluste...
old town Oamaru. by the middle of the night the blue eyed penguins are walking down the streets to their clusters
view through the cluster of foreground buildings to the tower on the North Lodge and Chilton House beyond
"The image is more than an idea. It is a vortex or cluster of fused ideas and is endowed with energy."
--Ezra Pound, 1885-1972, American poet, critic and figure of early modernist movement--
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The open cluster M47. 20x1 minute exposures taken prime focus through a Celestron C8NGT (8" Newtonian reflector, f5).
This image was taken through an insane amount of light-pollution - being so close to the horizon meant I was contending with both street lights, and the lights of a nearby school which lights up the Southern horizon. I'd be hard pressed to give this image a black background, but I've done the best I can!
Still getting to grips with deconvolution in Lynkeos, so there's still the problem of fringing around the stars.
The Beehive Cluster (a.k.a. Praesepe or Messier 44), in the center of the constellation Cancer. It is faintly visible by naked eye as a blob in Houston TX. M44 is a quite big star cluster, so only a focal length of 135mm is needed.
相機/Camera: Canon EOS 40D
鏡頭/Lens: Canon EF 28-135mm F4-5.6 IS USM
焦距/Focal length: 135mm
光圈/Aperture: f/5.6
快門速度/Shutter speed: 2s
總曝光時間/Total exposure time: 5m44s
感光度/ISO: 800
共172張圖以DeepSkyStacker疊合而成/Stacked from 172 images using DeepSkyStacker.
Family:Moraceae
Conservation status:Not at risk
Common name:Red Leaf Fig; Fig, Red Leaf; Fig, Cluster; Fig; Cluster Fig
Figs on leafless branches on the stem and also on the leafy twigs. Figs globular, about 15 × 18 mm. Orifice closed by interlocking apical and internal bracts.
North East Queensland.
Canon 550D Tamron SP AF 90 mm f/2.8 Di
The Perseus Galaxy Cluster is one of the largest objects in the known Universe. It is estimated to have up to 3000 galaxies that are bound together by the their mutual gravitational forces. Some of the closer galaxies in the cluster can be seen in the above image as the small brownish-beige objects scatters throughout the central area of the photo. (Click on the image to see an enlarged version that reveals the individual galaxies better.)
The galaxies are located about 250 million light-years from Earth, about 100 times further than our neighbor Andromeda Galaxy M31. The galaxies in the photo are actually quite large but their enormous distance renders them small. The cluster is being carried away from our Milky Way Galaxy at a speed of 3,500 miles/sec due to the expanding Universe. The light that produced this image left the cluster during the Triassic geological period on Earth at a time when dinosaurs had not yet evolved into existence from their ancestors and all of today's individual seven continents on Earth were joined into one giant continent named Pangaea.
A Plane Wave 431 mm (17") f/4.5 CDK astrograph equipped with a FLI-PL 6303E CCD monochrome camera was used to acquire the above image. Luminance, Red, Green, and Blue filters where used take filtered monochrome images. CCDStack2 was used to prepare the data for color blending in Photoshop to produce the single composite image above. This robotic astrograph is located at the New Mexico Skies Observatories in Mayhill, NM and is controlled remotely over the Internet by iTelescope.net members around the world.
Clustered Bellflower. Surface sow at 70F; maintain even moisture, expect germination in 2 to 3 weeks.
Taken with a 31.75cm RCOS Ritchey Chretien working at F9 and a SBIG STL6303E CCD camera.
LRGB 70:60:70:70 using Astrodon near infrared filters. The luminance has zero response shorter than 700nm and R,G and B peak at 850, 830 and 750nm respectively
Viikki Church of the Vine (2005) .
for the Malmi parrish.
Agronominkatu 5 .
FIN-00790 Viikki (Helsinki).
Finland
JKMM architects (Samuli Miettinen).
Altar triptych "The Tree of Life" (Elämän puu) by artist Antti Tanttu
See the rest of the set here
© picture by Mark Larmuseau
M13 is about 145 light-years in diameter. It is a globular cluster composed of several hundred thousand stars, M13 is 25,100 light-years away from Earth.
The Arecibo message of 1974, designed to communicate the existence of human life to hypothetical extraterrestrials, was transmitted toward M13. The reason was that with a higher star density, the chances of a life harboring planet with intelligent life forms, were believed to be higher. Even though the message was transmitted, M13 will no longer be in that location when it arrives. The sending of the message was more of a technological demonstration, rather than an actual attempt to contact life.
Equipment:
Orion Optics VX10 scope, Skywatcher NEQ6 mount, Mono Atik 383L camera, Starlight Xpress Superstar Auto-guider.
Frames:
7 X 240s lights plus darks
Processing:
Stacked and processed in Astroart 5.0.
Famous Scots data, scraped from Wikipedia (en.wikipedia.org/wiki/Famous_Scots) page, clustered on page outlinks using a KMeans algorithm.
Focus is on a cluster related to Brian Cox/Billy Connolly. More details at bit.ly/Hc41un.