Milky Way

The Milky Way, home to the Solar System, is one of the densest, most massive spiral galaxies known, and the dominant member of the Local Group by mass. While its stellar disc is physically smaller than Andromeda's, our home galaxy has about half again the mass of its already giant neighbor, at least 1.9 trillion Solar Masses, about a third of which is baryonic, and half of that luminous. This suggests a total stellar population around 600 billion, but could be as high as a few trillion.

An extremely pronounced bar structure appears to dominate the central region of the Milky Way, suggesting that the galaxy has yet to encounter a major collision event, though eventually Andromeda will make such a collision. The central black hole, massing an estimated 2.6 million solar masses, is exceedingly tiny compared to the expected average of a billion solar masses for a galaxy of such mass.

---

Including the region that harbors Sol, there are five regions in the Milky Way believed likely to harbor Earthlike worlds. This includes the region the dyrajt hail from, which is the largest such galactic habitable zone.