NGC 3115 - Spindle Galaxy in Sextans

NGC 3115, widely known as the Spindle Galaxy, is a striking lenticular galaxy located in the constellation Sextans at a distance of roughly 30–35 million light-years. Seen almost perfectly edge-on, it presents a razor-thin profile with a bright, elongated central bulge and a sharply defined disk, giving it a clean, minimalist appearance that immediately sets it apart from more chaotic spiral systems.

Messier 102 is sometimes also referred to as the Spindle Galaxy, but its identity has long been debated and it is most commonly associated with NGC 5866—a different edge-on lenticular system in Draco—so it should not be confused with NGC 3115, which is the Spindle Galaxy featured in this image.

Although it resembles an edge-on spiral at first glance, NGC 3115 is classified as an S0 (lenticular) galaxy, representing an evolutionary bridge between spirals and ellipticals. It contains very little gas and shows no significant ongoing star formation, which is why its disk appears smooth and subdued rather than clumpy or richly structured. A thin dust lane runs along the midplane, subtle but distinct, providing one of the few visual clues that this galaxy once had a more spiral-like past.

Scientifically, NGC 3115 is notable for hosting one of the nearest and most massive supermassive black holes known relative to its galaxy’s size. Measurements of stellar motions in its core were among the first to provide strong dynamical evidence for a billion-solar-mass black hole in a nearby galaxy, making NGC 3115 a cornerstone object in the study of galactic nuclei. Surrounding the galaxy is an extended halo populated by a rich system of globular clusters, hinting at a complex formation history involving mergers and early accretion events.

This image is based on 6 hours and 40 minutes of LRGB integration captured with Telescope Live’s CHI-1-CCD.