Ngc 3359 is a barred spiral galaxy in the constellation Ursa Major, at a distance of approximately 50 - 60 Mly. Gravitationally bound to this Milky Way sized galaxy is a small Blue Compact Galaxy, dubbed "Little Cub" (so named because of the constellation Ursa Major, Great Bear).
Ngc 3359 has many star forming regions that are visible across the disk. The galaxy has a pronounced bar, which is a relatively new feature. Research has shown that this feature is only approximately 500 million years old, whereas the galaxy itself is up to 10 billion years of age. Also unusual is the fact that the star forming regions extend very close or even into this bar.
The arms of ngc 3359 extend much further than what is usually shown in images of this galaxy. At both the 4 o'clock and 10 o'clock positions there are faint knots visible in this image that are either satellite galaxies of extensions of the spiral arms.
The Little Cub is a "Blue Compact Galaxy" or an "extremely metal-poor star forming galaxy". It has a very low oxygen content, ant its stars contain mostly only Hydrogen and Helium. This type of galaxy therefore resembles galaxies that formed when the universe was still young.
The Little Cub is gravitationally bound to ngc 3359, and is actually being ripped apart by it. Scientists have found a stream of molecular Hydrogen which stretches from Little Cub towards ngc 3359.
Little Cub has a brightness of approximately magnitude 19.5 - 20. The location of the Little Cub in the image is found here:
https://www.astrobin.com/42o6j0/
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