TrevorW
20-03-2009, 10:54 AM
Target: Fornax Galaxy Cluster (see how many you can find)
Camera: Canon 350d modified
Exposure Capture: DLSR Focus
Scope: SV80ED
Mount: EQ6 Pro
Exposure Setting: Prime focus, ISO800 ICNR off Daylight WB
Exposures: 12 x 330s total 66 minutes taken 18/03/09 between 9:00-11:00pm
Seeing: Average, light pollution bad
Guiding: Orion Starshoot Autoguider using PHD
Focus: DSLR Focus
Stacking: DSS, no darks or flats applied
Processing: PS7
Note: Originally I hoped to collect 2 hours of data but Fornax fell below my roof line and secondly the darks I thought I'd taken got lost in the ether somewhere. Personally I'm impressed by the number of galaxies evident except unfortunately NGC1365 although the direction I was shooting was in line with a street light at the front of my house which is hidden by the roof.
Info: Situated in Fornax
The second richest cluster of galaxies within 100 million light-years, although it is much smaller than the Virgo Cluster; it lies primarily in the constellation Fornax. There are actually two neighboring clusters, Fornax I and Fornax II (also known as the Eridanus Group), which contain 30 to 40 large galaxies each
Galaxy clusters, where hundreds or even thousands of galaxies inhabit dense quarters, provide a busy environment, an excellent place to look for intense galaxy interactions. Even the relatively innocent-looking nearby (60 million light years) Fornax cluster has an example of cataclysmic galaxy evolution in progress. Fornax appears to be a quiet place, even a bit dull, being dominated by old galaxies, ellipticals and S0's mostly. This appearance is deceiving, however; X-ray images reveal a more turbulent picture of a cluster in the late stages of a recent merger of a sizable subgroup with the main cluster. A recent closer look at the relative motions of the galaxies has revealed additional evidence for not one but two subunits of galaxies colliding with the main group.In retrospect, Fornax contains a prominent visual clue that the cluster is not entirely serene: NGC1427A, the only gas-rich irregular galaxy in the cluster, has an unusual "swoosh'' morphology with prominent blue knots of ongoing star formation. It also has a high velocity relative to the main cluster (about 600 km/s) and is probably part of one of the subgroups making its first passage through the main cluster. NGC1427A is relatively isolated, though, so its unusual appearance and vigorous star formation cannot be blamed on interaction with any particular large companion, but instead must be caused by the cluster as a whole. The motions of the stars which make up NGC1427A are distorted, and part of the galaxy appears to be breaking away to the north. This is highly suggestive that NGC1427A will not long survive as an identifiable galaxy passing through the cluster, but will be disrupted, spilling its stars and gas into the intergalactic regions of the Fornax cluster.
Camera: Canon 350d modified
Exposure Capture: DLSR Focus
Scope: SV80ED
Mount: EQ6 Pro
Exposure Setting: Prime focus, ISO800 ICNR off Daylight WB
Exposures: 12 x 330s total 66 minutes taken 18/03/09 between 9:00-11:00pm
Seeing: Average, light pollution bad
Guiding: Orion Starshoot Autoguider using PHD
Focus: DSLR Focus
Stacking: DSS, no darks or flats applied
Processing: PS7
Note: Originally I hoped to collect 2 hours of data but Fornax fell below my roof line and secondly the darks I thought I'd taken got lost in the ether somewhere. Personally I'm impressed by the number of galaxies evident except unfortunately NGC1365 although the direction I was shooting was in line with a street light at the front of my house which is hidden by the roof.
Info: Situated in Fornax
The second richest cluster of galaxies within 100 million light-years, although it is much smaller than the Virgo Cluster; it lies primarily in the constellation Fornax. There are actually two neighboring clusters, Fornax I and Fornax II (also known as the Eridanus Group), which contain 30 to 40 large galaxies each
Galaxy clusters, where hundreds or even thousands of galaxies inhabit dense quarters, provide a busy environment, an excellent place to look for intense galaxy interactions. Even the relatively innocent-looking nearby (60 million light years) Fornax cluster has an example of cataclysmic galaxy evolution in progress. Fornax appears to be a quiet place, even a bit dull, being dominated by old galaxies, ellipticals and S0's mostly. This appearance is deceiving, however; X-ray images reveal a more turbulent picture of a cluster in the late stages of a recent merger of a sizable subgroup with the main cluster. A recent closer look at the relative motions of the galaxies has revealed additional evidence for not one but two subunits of galaxies colliding with the main group.In retrospect, Fornax contains a prominent visual clue that the cluster is not entirely serene: NGC1427A, the only gas-rich irregular galaxy in the cluster, has an unusual "swoosh'' morphology with prominent blue knots of ongoing star formation. It also has a high velocity relative to the main cluster (about 600 km/s) and is probably part of one of the subgroups making its first passage through the main cluster. NGC1427A is relatively isolated, though, so its unusual appearance and vigorous star formation cannot be blamed on interaction with any particular large companion, but instead must be caused by the cluster as a whole. The motions of the stars which make up NGC1427A are distorted, and part of the galaxy appears to be breaking away to the north. This is highly suggestive that NGC1427A will not long survive as an identifiable galaxy passing through the cluster, but will be disrupted, spilling its stars and gas into the intergalactic regions of the Fornax cluster.