English: The Milky Way Galaxy is the barred spiral galaxy that contains the Solar System - A 200,000 ly wide visible disc, with a dark matter halo 10 times wider - 100 to 400 billion stars and at least that number of planets - Centered by a supermassive black hole of 4,100 million solar masses (27,000 ly away) - The constant rotation speed of stars and gases at various distances from the center (220 km/s) suggests that about 90% of the mass is invisible (dark matter) - Moving as a whole at 600 km/s - Second in size in the Local Group, which forms part of the Virgo Supercluster, which is a component of the Laniakea Supercluster -