Object of the Week, June 19, 2022 - NGC 6670 "The Poster Girl"
NGC 6670 (PGC 62033, UGC 11284, CGCG 301-31, MCG 10-26-44, 7ZW 812)
size: 1.1' x 0.5'
magnitude: 14.3vmag
Pair of interacting galaxies in Draco
NGC 6670A (NGC 6670-2, NGC 6670E)
18h33m37.72s, +59d53m22.8s
NGC 6670B (NGC 6670-1, NGC 6670W)
18h33m34.09s, +59d53m17.6s
No simply object as usual by me today, but a more interesting pair when it comes to form a beauty in the sky - the peculiar pair of interacting galaxies in Draco NGC 6670 witch shows slightly different edge-on angles and some starburst activities. In 2008 the pair becomes fame as a "Poster Girl", a compilation of interacting pairs illustrated by the HST.
Discovered at July 31, 1886 by Lewis Swift, he describes the not resolved pair as "extremely faint, small, considerably elongated and extremely difficult". He uses a 16" Refractor at Warner Observatory. So, in summery a later discovered visual object with a relative large and modern telescope from which we can conclude some observations better today than from the more unknown speculum mirrors.
Not unusual enough I found an for me uncommon designation. Because Swift did not record a separation, we found an "1" and "2" in the NGC. Even so NED divided the both main galaxies in an "A" and "B". New to me was the "E" and "W", which stands for the sky direction "west" and "east". NED also accepts theses abbreviations and science took them over. Anyone who knows the origin?
Little science is known about this beauty. Both are located around 400 million light-years away from Earth and seems to have one close encounter and is now in the early stages of a second. Wang et al [2001AJ....122..140W] classify the galaxy as a luminous infrared galaxy (LIRGs) and discovered long H I tidal tails and concluded the current interacting status. They also suggests active star formation in the nuclear regions of the galaxies.
In the 20-inch telescope galaxy E is visible with direct vision as a 3:1 elongated and slightly concentrated object with a very faint spot at the eastern end. W is visible as a faint, structureless pin. The 27-inch shows similar details while the W seems to be a little bit bend.
Reply With Quote