Milky Way
The Milky Way galaxy, a barred spiral galaxy containing between two and four hundred billion stars, is just one of many galaxies in the observable universe, though the Milky Way has special significance to Humanity as it is the home galaxy of its planet, Earth. The Milky Way is a barred spiral galaxy of SBc classification on the Hubble Sequence. It has two major arms, each sporting several minor arms that stem off of the major arm. One of these major arms, the Carina and Sagittarius Arm, is home to the Orion Arm. Splotches of intense star birth and formation can be seen in the arms. These areas are pink/red in hue and appear as wisps or clouds situated in the galactic plane.
The Milky Way is composed of a disk, in which all the arms and the majority of galactic matter lies, and the galactic bulge, essentially the center of a galaxy. The bulge is home to the galactic nucleus, the dead center of a galaxy and home to an extremely dense clustering of ancient stars. The nucleus is also thought to support a supermassive blackhole. Additionally, most known galaxies possess a halo of old and dying star clusters left over from the galaxy's formation. These clusters are situated up to 100,000 light years from the galactic bulge. Habitable planets may certainly lie within the halo, and some clusters may escape the range of the Halo Effect given their distance from the galactic center.
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