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Iota's Ghost
NGC5102 4hr48minutes captured last night Bortle 6 skies,a tough target to process nicely as it is a diffuse, mag 9.65 galaxy hiding in the glare of the much closer (approx 59 light years) Iota Centauri, a star of magnitude 2.75
This is a lenticular galaxy in the Centaurus A/M83 Group of galaxies. It was discovered by John Herschel in 1835.
Distance measurements
At least two techniques have been used to measure the distance to NGC 5102. The surface brightness fluctuations distance measurement technique estimates distances to spiral galaxies based on the graininess of the appearance of their bulges. The distance measured to NGC 5102 using this technique is 13.0 ± 0.8 Mly (4.0 ± 0.2 Mpc). However, NGC 5102 is close enough that the tip of the red giant branch (TRGB) method may be used to estimate its distance. The estimated distance to NGC 5102 using this technique is 11.1 ± 1.3 Mly (3.40 ± 0.39 Mpc). Averaged together, these distance measurements give a distance estimate of 12.1 ± 0.7 Mly (3.70 ± 0.23 Mpc).
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