[{"n": "BL Lacertae object", "u": "/e/galaxies-and-their-properties/bl-lacertae-object/", "s": "Active galactic nuclei with rapid variability and featureless spectra."}, {"n": "Brightest cluster galaxy", "u": "/e/galaxies-and-their-properties/brightest-cluster-galaxy/", "s": "The most massive galaxies, found at cluster centers."}, {"n": "Dark galaxy", "u": "/e/galaxies-and-their-properties/dark-galaxy/", "s": "Hypothesized galaxies made of dark matter, with no visible stars."}, {"n": "Dark matter halo", "u": "/e/galaxies-and-their-properties/dark-matter-halo/", "s": "Invisible mass scaffold that shapes and binds every galaxy."}, {"n": "Dwarf elliptical galaxy", "u": "/e/galaxies-and-their-properties/dwarf-elliptical-galaxy/", "s": "Small elliptical galaxies common in groups and clusters."}, {"n": "Field galaxy", "u": "/e/galaxies-and-their-properties/field-galaxy/", "s": "A galaxy gravitationally alone, not in a group or cluster."}, {"n": "Galactic halo", "u": "/e/galaxies-and-their-properties/galactic-halo/", "s": "Extended spherical component of a galaxy beyond its visible parts."}, {"n": "Galactic tide", "u": "/e/galaxies-and-their-properties/galactic-tide/", "s": "Tidal force from a galaxy's gravitational field."}, {"n": "Grand design spiral galaxy", "u": "/e/galaxies-and-their-properties/grand-design-spiral-galaxy/", "s": "Spiral galaxy with prominent, well-defined continuous arms."}, {"n": "Hubble sequence", "u": "/e/galaxies-and-their-properties/hubble-sequence/", "s": "A morphological galaxy classification scheme published by Edwin Hubble in 1926."}, {"n": "Interacting galaxy", "u": "/e/galaxies-and-their-properties/interacting-galaxy/", "s": "Galaxies whose gravity disturbs one another."}, {"n": "Low surface brightness galaxy", "u": "/e/galaxies-and-their-properties/low-surface-brightness-galaxy/", "s": "Diffuse galaxies dominated by dark matter, with faint stellar disks."}, {"n": "Luminous infrared galaxy", "u": "/e/galaxies-and-their-properties/luminous-infrared-galaxy/", "s": "Galaxies that outshine the Sun by 100 billion times in infrared."}, {"n": "Magellanic spiral", "u": "/e/galaxies-and-their-properties/magellanic-spiral/", "s": "Dwarf spiral galaxies with a single prominent arm, often complex."}, {"n": "Peculiar galaxy", "u": "/e/galaxies-and-their-properties/peculiar-galaxy/", "s": "Galaxies of unusual size, shape, or composition."}, {"n": "Ring galaxy", "u": "/e/galaxies-and-their-properties/ring-galaxy/", "s": "A galaxy with a ring-shaped structure of stars and gas."}, {"n": "Satellite galaxy", "u": "/e/galaxies-and-their-properties/satellite-galaxy/", "s": "Smaller galaxies bound to larger hosts, key to cosmology."}, {"n": "Type-cD galaxy", "u": "/e/galaxies-and-their-properties/type-cd-galaxy/", "s": "Supergiant elliptical galaxies at the centres of rich clusters."}, {"n": "Unbarred spiral galaxy", "u": "/e/galaxies-and-their-properties/unbarred-spiral-galaxy/", "s": "A spiral galaxy without a central bar structure."}]