This image shows a part of Markarian's chain, without the kinks and perspective that wide fields offer -
@Andy Brown's recent
image captures this beautifully. Markarian, an Armenian astrophysicist first described the common recessive motion of these galaxies in the 1960s. Here you have the bottom of the chain from the giant elliptical galaxies M84 and M86 at right thought the 'eyes' NGC 4435 and 4438 centre, and to upper left NGC 4458 and NGC 4461, with NGC 4473 just peeping out top left. All these galaxies lie around 50-60 mLY from earth.
M84 contains a supermassive black hole at its core, with two jets visible in Hubble images, surrounded by dark matter. M86, unlike all its neighbours show strong blue shift, moving towards the Milky Way at ~250 km/s, and contains a large number of globular clusters. There appears to be a small galaxy embedded at 10 o'clock - whether this is a dwarf galaxy or background object is unclear to me, but remnants of these are found in the star streams surrounding the bright core.
The 'eyes' are interacting lenticular galaxies with NGC 4438 having evidence of this in the fine dust lanes and active bluish streams, ripped from the core. This could be due to the 'right eye' NGC 4435 or the giant M86 (NGC 4406). NGC 4461 and 4473 are a smaller pair of interacting 'eyes'.
I wanted to maximise the integration time on the chain, as dark nights are receding. Taken over three nights, this is just shy of 5 hours data, frustrated by clouds, although a lovely clear night to finish. I am enjoying imaging with my refractor set up, so easy to guide and much sharper than my SCT. I have brightened the galaxies in this image, to pick these out, along with the many smaller companions, from the background. As a result I feel I have lost some of the subtle colour and will produce a revision to highlight these features.
Comments