Question: Who is regarded as one of the most important astronomers of all time, and invented a morphological classification scheme for galaxies?

full_context: Document 1: Edwin Hubble: Edwin Powell Hubble (November 20, 1889 – September 28, 1953) was an American astronomer. He played a crucial role in establishing the fields of extragalactic astronomy and observational cosmology and is regarded as one of the most important astronomers of all time.
Document 2: Physical cosmology: Physical cosmology is the study of the largest-scale structures and dynamics of the Universe and is concerned with fundamental questions about its origin, structure, evolution, and ultimate fate. Cosmology as a science originated with the Copernican principle, which implies that celestial bodies obey identical physical laws to those on Earth, and Newtonian mechanics, which first allowed us to understand those physical laws. Physical cosmology, as it is now understood, began with the development in 1915 of Albert Einstein's general theory of relativity, followed by major observational discoveries in the 1920s: first, Edwin Hubble discovered that the universe contains a huge number of external galaxies beyond our own Milky Way; then, work by Vesto Slipher and others showed that the universe is expanding. These advances made it possible to speculate about the origin of the universe, and allowed the establishment of the Big Bang Theory, by Georges Lemaitre, as the leading cosmological model. A few researchers still advocate a handful of alternative cosmologies; however, most cosmologists agree that the Big Bang theory explains the observations better.
Document 3: Hubble sequence: The Hubble sequence is a morphological classification scheme for galaxies invented by Edwin Hubble in 1926. It is often known colloquially as the Hubble tuning fork diagram because of the shape in which it is traditionally represented.
Document 4: Galaxy morphological classification: Galaxy morphological classification is a system used by astronomers to divide galaxies into groups based on their visual appearance. There are several schemes in use by which galaxies can be classified according to their morphologies, the most famous being the Hubble sequence, devised by Edwin Hubble and later expanded by Gérard de Vaucouleurs and Allan Sandage.
Document 5: Malin 1: Malin 1 is a giant low surface brightness (LSB) spiral galaxy, the prototype of LSB galaxies. It is located 366 Mpc away in the constellation Coma Berenices, near the North Galactic Pole. s of 2015 it is the largest known spiral galaxy so far discovered, with an approximate diameter of 650000 ly , six and a half times the diameter of our Milky Way. It was discovered by astronomer David Malin in 1986 and is the first LSB galaxy verified to exist. As such, it is also the first giant LSB galaxy discovered. Its high surface brightness central spiral is 30000 ly across, with a bulge of 10000 ly . The central spiral is a SB0a type barred-spiral.
Document 6: Elliptical galaxy: An elliptical galaxy is a type of galaxy having an approximately ellipsoidal shape and a smooth, nearly featureless brightness profile. Unlike flat spiral galaxies with organization and structure, they are more three-dimensional, without much structure, and their stars are in somewhat random orbits around the center. They are one of the three main classes of galaxy originally described by Edwin Hubble in his 1936 work "The Realm of the Nebulae", along with spiral and lenticular galaxies. Elliptical galaxies range in shape from nearly spherical to highly flat and in size from tens of millions to over one hundred trillion stars. Originally Edwin Hubble hypothesized that elliptical galaxies evolved into spiral galaxies, which was later discovered to be false. Stars found inside of elliptical galaxies are on average much older than stars found in spiral galaxies.
Document 7: Edmond Halley: Edmond (or Edmund) Halley, FRS (pronounced ; 8 November [O.S. 29 October] 1656 – 25 January 1742 [O.S. 14 January 1741] ) was an English astronomer, geophysicist, mathematician, meteorologist, and physicist who is best known for computing the orbit of Halley's Comet. He was the second Astronomer Royal in Britain, succeeding John Flamsteed.
Document 8: Hercules (dwarf galaxy): Hercules, or Her, is a dwarf spheroidal galaxy situated in the Hercules constellation and discovered in 2006 in data obtained by the Sloan Digital Sky Survey. The galaxy is located at a distance of about 140 kpc from the Sun and moves away from the Sun with a velocity of about 45 km/s. It is classified as a dwarf spheroidal galaxy (dSph). Her has a noticeably elongated (ratio of axes ~ 3:1) shape with a half-light radius of about 350 pc. This elongation may be caused by tidal forces acting from the Milky Way galaxy, meaning that Her is being tidally disrupted now. Her also shows some gradient of velocities across the galaxy's body and is embedded into a faint stellar stream, which also points towards its ongoing tidal disruption.
Document 9: Multiwavelength Atlas of Galaxies: The Multiwavelength Atlas of Galaxies is a textbook and atlas of 35 well studied galaxies (including our Galaxy) authored by Glen Mackie of the Centre for Astrophysics & Supercomputing, Swinburne University of Technology. It was originally published in 2011 by Cambridge University Press.
Document 10: Pillars of Creation: Pillars of Creation is a photograph taken by the Hubble Space Telescope of elephant trunks of interstellar gas and dust in the Eagle Nebula, some 6,500-7,000 light years from Earth. They are so named because the gas and dust are in the process of creating new stars, while also being eroded by the light from nearby stars that have recently formed. Taken on April 1, 1995, it was named one of the top ten photographs from Hubble by Space.com. The astronomers responsible for the photo were Jeff Hester and Paul Scowen from Arizona State University. The region was rephotographed by ESA's Herschel Space Observatory in 2011, and again by the Hubble in 2014 (see below).
Document 11: Holmdel Horn Antenna: The Holmdel Horn Antenna is a large microwave horn antenna that was used as a radio telescope during the 1960s at Bell Telephone Laboratories in Holmdel Township, New Jersey, United States. It was designated a National Historic Landmark in 1988 because of its association with the research work of two radio astronomers, Arno Penzias and Robert Wilson. In 1965 while using this antenna, Penzias and Wilson discovered the microwave background radiation that permeates the universe. This was one of the most important discoveries in physical cosmology since Edwin Hubble demonstrated in the 1920s that the universe was expanding. It provided the evidence that confirmed George Gamow's and Abbe Georges Lemaitre's "Big Bang" theory of the creation of the universe. This helped change the science of cosmology, the study of the history of the universe, from a field for unlimited theoretical speculation into a discipline of direct observation. In 1978 Penzias and Wilson received the Nobel Prize for Physics for their discovery.
Document 12: Canes Venatici: Canes Venatici is one of the 88 official modern constellations. It is a small northern constellation that was created by Johannes Hevelius in the 17th century. Its name is Latin for "hunting dogs", and the constellation is often depicted in illustrations as representing the dogs of Boötes the Herdsman, a neighboring constellation. Cor Caroli is the constellation's brightest star, with an apparent magnitude of 2.9. La Superba is one of the reddest stars in the sky and one of the brightest carbon stars. The Whirlpool Galaxy is a spiral galaxy tilted face-on to observers on Earth, and was the first galaxy whose spiral nature was discerned.
Document 13: Intermediate spiral galaxy: An intermediate spiral galaxy is a galaxy that is in between the classifications of a barred spiral galaxy and an unbarred spiral galaxy. It is designated as SAB in the galaxy morphological classification scheme. By definition, a galaxy is a congregation of stars held together by gravity. The first intermediate spiral galaxy discovered is the Milky Way, by Galileo, in 1610. He was the first person with a telescope powerful enough to make such a discovery. Before Galileo, it was thought that all bright objects in the sky were either the planets in the Solar System, moons, comets, or stars. Until the beginning on the twentieth century, astronomers did not know the size of the Universe, but speculated it to be about as big as the Milky Way. In 1920, at the National Academy of Science, there was a big debate between Harlow Shapley and Heber D. Curtis on whether nebulae are small globular clusters surrounding the Milky Way, or separate galaxies located farther away. Nothing was resolved at the debate; neither side was able to provide conclusive evidence to prove their side correct over their opponent. In 1923, Edwin Hubble resolved the matter with a photograph that he took of the Andromeda Galaxy. What he found in his photograph was a very bright light source pulsing at a certain rate, a Cepheid variable, located outside the Milky Way. This can be used to determine the distance to it. Hubble proved that the Universe was full of galaxies, and disproved that the Milky Way was the extent of the Universe. There are many types of galaxies in the Universe, elliptical, barred spiral galaxies; they vary in shape and size, but on average spiral galaxies are the most abundant.
Document 14: Lenticular galaxy: A lenticular galaxy is a type of galaxy intermediate between an elliptical and a spiral galaxy in galaxy morphological classification schemes. Lenticular galaxies are disc galaxies (like spiral galaxies) that have used up or lost most of their interstellar matter and therefore have very little ongoing star formation. They may, however, retain significant dust in their disks. As a result, they consist mainly of aging stars (like elliptical galaxies). Because of their ill-defined spiral arms, if they are inclined face-on it is often difficult to distinguish between them and elliptical galaxies. Despite the morphological differences, lenticular and elliptical galaxies share common properties like spectral features and scaling relations. Both can be considered early-type galaxies that are passively evolving, at least in the local part of the Universe.
Document 15: Hubble European Space Agency Information Centre: The Hubble European Space Agency Information Centre (HEIC) is a science communication office, established at the Space Telescope - European Coordinating Facility (ST-ECF) in Munich, Germany late in 1999. This initiative was taken so as to fulfil the NASA/ESA Hubble Space Telescope (HST) outreach and education tasks for the European Space Agency (ESA), as outlined in an agreement between NASA and ESA.
ground_truth: Edwin Hubble