Illusions in M104
Posted 22 May 2013 - 10:05 PM
1) The northern edge of the dust lane forms an obtuse angle rather than an arc. I haven't heard of others seeing this, though - maybe it is just me. The edge is not ideally circular in good photos, but the degree of straightness on either side of the nucleus that I perceive must be illusory.
2) Bright enhancements within the northern half, E and W of the central core. Nothing comparable can be seen in photos (including the specially scaled ones in the de Vaucouleurs Atlas). What is perceived visually must rather be similar to "arcs" next to the core that are often seen in elliptical galaxies - where it is certainly an illusion.
3) The glow south of the dust lane curves around the ends of the lane. Photos do show a halo enveloping the galaxy, but it is exceedingly faint. The glow we perceive is most likely illusory and due to the excessive contrast formed by the bright edge-on with the background sky: the eye-brain "pads" it to soften the transition.
4) Details in the dust lane. There are some in photographs that may conceivably be visible with really large scopes; I refer however to those "details" that are relatively easily seen. I see the dark lane as broken E and W of the nucleus at lower magnifications in my 16" but not at higher ones. Since these should be small, high-contrast features, they should be seen better at higher magnifications. I conclude that they are illusory.
In conclusion, M104's real beauty lies in its striking visual simplicity. By rights it should be a relatively plain-looking galaxy, but it is adorned with illusions.
What do you think?
Posted 22 May 2013 - 10:36 PM
Posted 23 May 2013 - 01:38 AM
Posted 23 May 2013 - 02:09 PM
Posted 23 May 2013 - 03:28 PM
Regardless, we see what we see and it's great fun to compare that to photos, especially if you've made a sketch. This often leads to more observing and sketching of the same object which more often than not will lead to seeing more and more with increasing certainty.
Posted 23 May 2013 - 10:41 PM