M102 - The Spindle Galaxy

Messier 102 (commonly identified with NGC 5866) is an edge-on lenticular galaxy (type S0) located in the northern constellation Draco, about 44–50 million light-years away. With an apparent magnitude of 10.7 and a size of 4.7 × 1.9 arcminutes, it spans roughly 60,000 light-years across - about two-thirds the diameter of the Milky Way. Seen almost exactly edge-on, M102 presents a striking central dust lane cutting across its bulge, an unusual feature for a lenticular galaxy. The Hubble Space Telescope reveals a reddish bulge surrounding a bright nucleus, a blue stellar disk parallel to the dust lane, and a faint extended halo. The galaxy is estimated to host around 100 billion stars, and the warped dust lane suggests a past interaction or merger. M102 is a prominent member of the NGC 5866 Group (or M102 Group), which also includes galaxies such as NGC 5907 and NGC 5879. The galaxy is receding from us at 672 km/s. Interestingly, the north celestial pole passes within a degree of M102 every ~25,800 years - most recently around 4900 BC, and it will do so again in the year 20900 AD.

M102 was discovered in 1781 by Pierre Méchain, who described it as a faint nebula “between the stars Omicron Boötis and Iota Draconis.” He reported it to Charles Messier, who included it in his catalog. Confusion later arose when Méchain wrote that M102 was a duplicate observation of M101, sparking a long-standing debate. However, most historians and observers today identify NGC 5866 as Messier’s intended object. The galaxy was independently rediscovered by William Herschel in 1788, and later studied by John Herschel, William Parsons (Lord Rosse), and many others, each noting its elongated form and central dark lane.

Image captured using the SPA-2-CCD system over 2h40m of LRGB integration.

Sources:

en.wikipedia.org

www.messier-objects.com

Data credit: Telescope.Live