M102

The Spindle Galaxy (NGC 5866) is a lenticular galaxy in Draco, about 50 million light-years from Earth. It is seen nearly perfectly edge-on, presenting a thin, spindle-shaped disk bisected by a sharp, prominent dust lane. The galaxy spans about 60,000 light-years. The identity of M102 has been debated — it may be a duplicate observation of M101, but most modern catalogs identify it with NGC 5866.

Located about 2.5 degrees southwest of Iota Draconis. In a telescope it appears as a thin, bright streak with a prominent central bulge — one of the finest edge-on galaxies in the Messier catalog. The dark dust lane across the center is visible in 6-inch or larger telescopes under good conditions. The narrow, elegant profile makes it easy to identify. Best observed from April through August.

The history of M102 is tangled. Pierre Mechain reported it to Messier in 1781, but later claimed it was a duplicate of M101. However, the position Mechain gave better matches NGC 5866 (the Spindle Galaxy). Most modern Messier lists include NGC 5866 as M102.