NGC 3395 and NGC 3396 (aka Arp 270)
An Interacting pair of Galaxies

NGC 3395 and NGC 3396, are a pair of closely interacting galaxies that appear to be in contract. Both are in the IRAS catalog of infrared sources, and this indicates massive star formation. However, neither galaxy is a particularly bright infrared object, and thus they have probably not actually collided.

One current theory would suggest that these two are in the process of merging into a single elliptical galaxy. Some astronomers predict that this is the fate that awaits the Milky Way and spiral galaxy M-31 in about 5 billion years.

This pair is included in Arp’s catalog of unusual galaxies as ARP 270. Using the red shift data from the “NASA Extra-galactic Data Base(NED)”, and a Hubble Constant of 62 Km per sec., per Megaparsec, one can calculate a rough distance and size for NGC 3395 as: Distance = 85 million light years; Diameter = 52,200 light years. NGC 3396 has the same red shift, which shows that both galaxies are at nearly the same distance.

NGC 3395 (ARP 270) Magnitude: 12.5 Constellation: Leo Minor RA: 10h 49m 49.4s Dec: +32° 58' 51" Epoch 2000 Size (mins): 2.1' x 1.2' Classification: SAB(rs)cd pec: III        Mixed Barred Non-barred Spiral, mixed Inner Ring S-shaped, peculiar, Luminosity Class III Deep Sky Field Guide:        "Very small, very bright nucleus; two main bright knotty arms, IC 2605 is one arm."

NGC 3396 (ARP 270) Magnitude: 12.6 Constellation: Leo Minor RA: 10h 49m 56.1s Dec: +32° 59' 22" Epoch 2000 Size (mins): 3.0' x 1.2' Classification: IBm pec        Barred Irregular, peculiar Deep Sky Field Guide:     "Very bright bar 0.7x0.2 arc min."

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George Normandin, KAS

June 25th, 2000