Question: What is the apparent magnitude of the spiral galaxy discovered by Frank Leavenworth?

Context paragraphs:
Francis Preserved Leavenworth: Francis Preserved Leavenworth (born September 3, 1858 in Mount Vernon, Indiana; died November 12, 1928; a.k.a. "Frank Leavenworth") was an American astronomer.  He discovered many New General Catalogue objects together with Frank Muller and Ormond Stone.  They used a telescope with a 66-cm aperture at the Leander McCormick Observatory at the University of Virginia in Charlottesville, Virginia.

NGC 166: NGC 166 (also known as PGC 2143) is a spiral galaxy located around 2.6 million light-years away in the constellation Cetus, with an apparent magnitude of 15.18.  It was discovered by Francis Preserved Leavenworth in 1886.

Sombrero Galaxy: Sombrero Galaxy (also known as Messier Object 104, M104 or NGC 4594) is an unbarred spiral galaxy in the constellation Virgo located 31.13 Mpc from Earth.  The galaxy has a diameter of approximately 15kpc (50,000 light-years), 30% the size of the Milky Way.  It has a bright nucleus, an unusually large central bulge, and a prominent dust lane in its inclined disk.  The dark dust lane and the bulge give this galaxy the appearance of a sombrero.  Astronomers initially thought that the halo was small and light, indicative of a spiral galaxy, but Spitzer found that the halo around the Sombrero Galaxy is larger and more massive than previously thought, indicative of a giant elliptical galaxy.  The galaxy has an apparent magnitude of +8.0, making it easily visible with amateur telescopes, and it is considered by some authors to be the brightest galaxy within a radius of 10 megaparsecs of the Milky Way.  Its large bulge, its central supermassive black hole, and its dust lane all attract the attention of professional astronomers.

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.

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.

SN 2011fe: SN 2011fe, initially designated PTF 11kly, was a Type Ia supernova discovered by the Palomar Transient Factory (PTF) survey on 24 August 2011 during an automated review of images of the Messier 101 from the nights of 22 and 23 August 2011.  It was located in Messier 101, the Pinwheel Galaxy, 21 million light years from Earth.  It was observed by the PTF survey very near the beginning of its supernova event, when it was approximately 1 million times too dim to be visible to the naked eye.  It is the youngest type Ia ever discovered.  About 13 September 2011, it reached its maximum brightness of apparent magnitude +9.9 which equals an absolute magnitude of about -19, equal to 2.5 billion Suns.  At +10 apparent magnitude around 5 September, SN 2011fe was visible in small telescopes.  As of 30 September the supernova was at +11 apparent magnitude in the early evening sky after sunset above the northwest horizon.  It had dropped to +13.7 as of 26 November 2011.

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.

NGC 90: NGC 90 is an interacting spiral galaxy estimated to be about 300 million light-years away in the constellation of Andromeda.  It was discovered by R. J. Mitchell in 1854 and its apparent magnitude is 13.7.  The galaxy is currently interacting with NGC 93 and exhibits two highly elongated and distorted spiral arms with bright blue star clusters indicative of star formation, likely caused by the interaction with its neighbor.

NGC 2: NGC 2 is a spiral galaxy in the constellation Pegasus, discovered by Lawrence Parsons, 4th Earl of Rosse on 20 August 1873, and was described as "very faint, small, south of NGC 1."  It lies slightly to the south of NGC 1.  It is a faint spiral galaxy of apparent magnitude 14.2.

NGC 5713: NGC 5713 is a peculiar, asymmetric galaxy in the constellation Virgo.  Although classified as a spiral galaxy by most galaxy catalogs, NGC 5713 galaxy is very different from most normal spiral galaxies.  While most spiral galaxies either have either two well-defined spiral arms or a filamentary spiral-like structure, this spiral galaxy has only one visible spiral arm in its disk.  This makes it a galaxy of the Magellanic type.  Gravitational interactions with the nearby spiral galaxy NGC 5719 may be responsible for producing the disturbed, asymmetric structure including the single spiral arm.

Supporting paragraphs: NGC 166 Francis Preserved Leavenworth
Answer: 15.18