Context: A spiral galaxy is a type of galaxy originally described by Edwin Hubble in his 1936 work "The Realm of the Nebulae" and, as such, forms part of the Hubble sequence. Spiral galaxies consist of a flat, rotating disk containing stars, gas and dust, and a central concentration of stars known as the bulge. These are surrounded by a much fainter halo of stars, many of which reside in globular clusters., NGC 5866 (also called the Spindle Galaxy or Messier 102) is a relatively bright lenticular or spiral galaxy in the constellation Draco. NGC 5866 was probably discovered by Pierre Méchain or Charles Messier in 1781, and independently found by William Herschel in 1788., The NGC 5866 Group is a small group of galaxies located in the constellation Draco. The group is named after NGC 5866, the galaxy with the highest apparent magnitude in the group, although some galaxy group catalogs list NGC 5907 as the brightest member., NGC 5907 is a spiral galaxy located approximately 50 million light years from Earth . It has an anomalously low metallicity and few detectable giant stars , being apparently composed almost entirely of dwarf stars . It is a member of the NGC 5866 Group . NGC 5907 has long been considered a prototypical example of a warped spiral in relative isolation . Then in 2006 , an international team of astronomers announced the presence of an extended tidal stream surrounding the galaxy that challenges this picture and suggests the gravitational perturbations induced by the stream progenitor may be the cause for the warp . NGC 5907 is also known as the Knife Edge or Splinter galaxy . The galaxy was discovered in 1788 by William Herschel . Supernova 1940A was in this galaxy ., A nebula (Latin for "cloud"; pl. nebulae, nebulæ, or nebulas) is an interstellar cloud of dust, hydrogen, helium and other ionized gases. Originally, "nebula" was a name for any diffuse astronomical object, including galaxies beyond the Milky Way. The Andromeda Galaxy, for instance, was once referred to as the "Andromeda Nebula" (and spiral galaxies in general as "spiral nebulae") before the true nature of galaxies was confirmed in the early 20th century by Vesto Slipher, Edwin Hubble and others., In astronomy and physical cosmology, the metallicity or Z is the fraction of mass of a star or other kind of astronomical object that is not in hydrogen (X) or helium (Y). Most of the physical matter in the universe is in the form of hydrogen and helium, so astronomers use the word "metals" as a convenient short term for "all elements except hydrogen and helium". This usage is distinct from the usual physical definition of a solid metal. The rationale for the astronomical usage is that in the high-temperature and pressure environment of a star, atoms do not undergo chemical reactions and effectively have no chemical properties, including that of being a metal as usually understood. For example, stars and nebulae with relatively high abundances of carbon, nitrogen, oxygen, and neon are called "metal-rich" in astrophysical terms, even though those elements are non-metals in chemistry., A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter. The word galaxy is derived from the Greek "", literally "milky", a reference to the Milky Way. Galaxies range in size from dwarfs with just a few billion stars to giants with one hundred trillion stars, each orbiting its galaxy's center of mass. Galaxies are categorized according to their visual morphology as elliptical, spiral and irregular. Many galaxies are thought to have black holes at their active centers. The Milky Way's central black hole, known as Sagittarius A*, has a mass four million times greater than the Sun. As of March 2016, GN-z11 is the oldest and most distant observed galaxy with a comoving distance of 32 billion light-years from Earth, and observed as it existed just 400 million years after the Big Bang., Subject: ngc 5907, Relation: constellation, Options: (A) andromeda (B) draco (C) sagittarius
Output: draco