Object of the Week – July 30, 2017 – UGC 10770 (Arp 32)

UGC 10770 (Arp 32, VV 89, KPG 506, MCG +10-24-107)

Galaxy pair in Draco

RA: 17 13 09
DEC: +59 19 40
Mag: 13.9 vmag
Size: 1.5’x0,5’

This unusual galaxy pair near the head of Draco looks like an airplane propeller. Arp classified this it in the subgroup “Integral sign spiral” which also indicate its morphology.

Astrophysical it is little known about the object. The pair is only around 48 million lights years away. In combination with its small size both galaxies has to be small one. Astronomers believe these touching galaxies as a result of a collision. A more precisely look shows to different morphologies within the galaxies. While the upper one shows nearly no star formation, the lower galaxy shows many knots and indicate a more active star formation. Damjanov et al. suspect an older stellar population for the upper galaxy.

Beside the astrophysics the galaxy is bright enough to spot it in mid size instruments. For my 16-inch it was an easy target and shows a 1/3 elongation with its foreground star in the middle (propeller axis). The 27-inch shows the remarkable integral sign form without showing any HII spots.

DSS 15'x15' blue
Attachment 2619

PanSTARRS 2'x2' g-filter
Attachment 2620

200-inch Hale Telescope
Attachment 2621

sketch: 27", 419x, NELM 6m5+
Attachment 2622

And as always,

Give it a go and let us know!

I didn't see any of the HII blobs either in Jimi's 48-inch, but it was a cool object (notes from May 2012) --

VV 89a, the brighter component of Arp 32, appeared fairly bright, moderately large, elongated 5:2 ~N-S, ~1.0' x 0.25'. It was brighter at the north end and dimmed at the south tip. The galaxy has an unusual banana shape, slightly bending out towards the west! A very faint star (or stellar knot) is just east of the north end. VV 89b (the attached northern component) appeared fairly faint, small, slightly elongated N-S, ~20"x15".

I observed this one just recently and recorded:

"Components resolved with 5.5 mm. Star in between. N component NS, SW end of S component bends sharply S, tapered." 16", 330x, SQM 21.7.