March 10, 2019

Arps in E Cam area

March 8, 2019. BMO 20" (F/5). SQM 21.0, good seeing. Arps in E Cam area.

Arp 9, DSS

Arp 9, NGC 2523, Cam. NE of a star. 13 mm: Bar WNW-ESE, small bright core in the middle. Short arm from E end of the bar, weakly CCW to half the distance from the bar end to the star. Stronger arm opposite, slightly longer. 8 mm: Enhanced edge of the halo curving from near the end of the SE arm to W end of the bar. Detached small enhancement beyond the end of the N arm, at almost twice the distance from the bar end.

Arp 17, DSS

Arp 17, UGC 3972, Cam. 8 mm: Diffuse object between m11 and m14 stars (on a line SW-NE). 5.5 mm: Within the halo, main component (PGC 21693) comma-shaped, comprising the small core and the enhanced SW edge like a short arm from W side of the core. Secondary component (PGC 21685) glimpsed intermittently as an enhancement on the N edge of the halo.

Arp 80, DSS

Arp 80, NGC 2633, Cam. 5.5 mm. N of the line between 2 m10 stars (SW-NE). [Sub-] threshold star E. Bright NS core or bar with a starlike center. CW arm from S end of bar, runs parallel to the core on E side, widely separated. Opposite arm is just a short enhanced segment on NW edge of the halo. The long arm points in the general direction of, but does not connect to an enhancement N of the bar, which is widely separated and forms a right triangle with the nucleus and the subthreshold (visible as a diffuse spot) star to the E.

Arp 141, DSS

Arp 141, UGC 3730, Cam. 5.5 mm. Star SW, fainter star NW. Core on N end. S of it is an enhancement vaguely continued S from its W edge, to about half the distance to the star. Small enhancement SE of the first, another one ENE of the star.

Arp 156, SDSS

Arp 156, UGC 5814, Dra. 5.5 mm. E of the faintest (m12) star in a group of 4. Overall, elongated NW-SE. Core on NW end, NE edge flattened and sharp. An almost detached small star cloud SE of the core.

Arp 181, SDSS

Arp 181, NGC 3212 and 3215. Dra. H [III.980 and 981], reobservation. 5.5 mm. Pair stretching ESE of an unequal pair of stars. -12 elongated EW immediately S of a faint star. -15 has a faint star on E edge. It is mainly comma-shaped with the "tail" pointing N from the SW edge of the core. The core is also vaguely extended toward the star from its N edge.