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The Virgo Galaxy Cluster - Markarian's Chain
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Copyright 2005 Hap Griffin
This is a wide-field shot of the western half of the remarkable galaxy cluster
in the constellation Virgo. If you look close, there are dozen's of
identifiable galaxies in this photograph. I am working on a clickable
overlay to label the various galaxies. Check back soon! However,
this low-resolution JPEG does not do this region justice. If you have a
broadband internet connection, I invite you to download the original
full-resolution TIF version of this photograph at http://www.machunter.org/images/VirgoCluster.tif
(right-click on the link and chose "Save Target As...") and open it in Photoshop or another graphics program able to handle uncompressed
TIF files. Zoom in close and slowly pan across this expanse of space
exploring the fantastic collection galaxies contained within.
The entire Virgo cluster contains some 2000 galaxies and represents an example of the largest structural unit in the Universe. It is gravitationally connected to the "Local Group" of galaxies of which our Milky Way is a member. While currently receding from the Virgo cluster, our Local Group is experiencing a slowdown because of its enormous gravity and will eventually be pulled into it.
The middle of this photograph is the collection of galaxies known as Markarian's Chain. The triangle of galaxies looking somewhat like a "face" at the lower right is anchored by the large linticular galaxy M86 with its close neighbor M84 to it's right. Below this pair and forming the "mouth" of the face, is the edge-on spiral NGC 4388. Above the "right eye" of the face and looking much like an "eyebrow" is another edge-on spiral, NGC 4402. Moving towards the left in this conspicuous chain is the interacting pair of galaxies, NGC 4438 and NGC 4435. Moving farther towards the left is the pair NGC 4461 and NGC 4458, followed by NGC 4473. The chain is completed by the pair of NGC 4477 and NGC 4479.
The large galaxy at the lower left is M87, the central galaxy in the Virgo Cluster. It is also a huge galaxy (larger than our own Milky Way) with a diameter of 120,000 light years and a mass of several trillion suns.
The galaxies of the Virgo Cluster lie at a distance of approximately 60 million light years. Thus, the light that arrived here on earth allowing this photograph to be taken originated shortly after the dinosaurs died out on our planet. When you pan through the hi-res version, contemplate about how you are literally a time travellor when looking at distant objects in our Universe.
Date/Location:
April 2, 2005 Griffin/Hunter
Observatory Bethune, SC
Instrument: Canon 300D Digital SLR (modified) through Orion
80mm ED80 APO refractor
Focal Ratio: Approx. f4.5 using Meade 0.6 Focal Reducer
Guiding: Auto through 10" Meade LX-200 w/ SBIG ST-237
Conditions: Visually clear but VERY windy
Weather: 50 deg. F
Exposure: 135 minutes total @ ISO 800 (27 x 5 min exposures) calibrated with flat frame
and Master Dark frame (average combine of 9 darks)
Filters: Baader UV/IR Block
Processing: Focused and captured with DSLRFocus.
RAW to TIFF conversion, frame calibrations, Digital Development,
Adaptive Richardson_Lucy deconvolution, scaling and JPEG conversion with ImagesPlus.
Frame alignment in Registar. Noise reduction with
NeatImage.