IC 4182 is a Magellanic spiral galaxy in the constellation

Canes Venatici Canes Venatici ( ) is one of the 88 constellations designated by the International Astronomical Union (IAU). 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 galaxy lies about 14 million

light years A light-year, alternatively spelled light year (ly or lyr), is a unit of length used to express astronomical distances and is equal to exactly , which is approximately 9.46 trillion km or 5.88 trillion mi. As defined by the International Astro ...

away from Earth, which means, given its apparent dimensions, that IC 4182 is approximately 28,000 light years across. It was discovered by German astronomer

Max Wolf Maximilian Franz Joseph Cornelius Wolf (21 June 1863 – 3 October 1932) was a German astronomer and a pioneer in the field of astrophotography. He was the chairman of astronomy at the University of Heidelberg and director of the Heidelberg-K� ...

on 21 March 1903. IC 4182 is seen nearly face-on. It has a low surface brightness disk with patch of star formation and no spiral pattern. The galaxy is close enough for its brightest stars to be resolvable through large telescopes, having a photometric blue filter apparent magnitude of 19.2, and a visual magnitude of around 20 for the brightest blue stars and around 21 for the brightest red stars. The density of

ultraviolet Ultraviolet radiation, also known as simply UV, is electromagnetic radiation of wavelengths of 10–400 nanometers, shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight and constitutes about 10% of ...

sources decreases monotonically with radius. SN1937CLightCurve

IC 4182 has been the home of one

supernova A supernova (: supernovae or supernovas) is a powerful and luminous explosion of a star. A supernova occurs during the last stellar evolution, evolutionary stages of a massive star, or when a white dwarf is triggered into runaway nuclear fusion ...

, SN 1937C ( type Ia, mag. 8.4).

Fritz Zwicky Fritz Zwicky (; ; February 14, 1898 – February 8, 1974) was a Swiss astronomer. He worked most of his life at the California Institute of Technology in the United States of America, where he made many important contributions in theoretical an ...

discovered the supernova, which was located 30 arcseconds north and 40 arcseconds east of the nucleus, on 24 August 1937. The supernova was a few days post maximum. The peak apparent B-magnitude was estimated to have been 8.7. The galaxy was observed by the

Hubble Space Telescope The Hubble Space Telescope (HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the Orbiting Solar Observatory, first space telescope, but it is one of the largest and most ...

, leading to the discovery of

Cepheid variable A Cepheid variable () is a type of variable star that pulsates radially, varying in both diameter and temperature. It changes in brightness, with a well-defined stable period (typically 1–100 days) and amplitude. Cepheids are important cosmi ...

stars within it. SN 1937C then became the first type Ia supernova to have its distance calibrated with Cepheid stars, and then used as

standard candle The cosmic distance ladder (also known as the extragalactic distance scale) is the succession of methods by which astronomers determine the distances to celestial objects. A ''direct'' distance measurement of an astronomical object is possible ...

s to calculate the

Hubble constant Hubble's law, also known as the Hubble–Lemaître law, is the observation in physical cosmology that galaxies are moving away from Earth at speeds proportional to their distance. In other words, the farther a galaxy is from the Earth, the faste ...

. The galaxy is considered to be a member of the

M94 Group The M94 Group (Canes I Group or Canes Venatici I Group) is a loose, extended group of galaxies located about 13 million light-years away in the constellations Canes Venatici and Coma Berenices. The group is one of many groups that lies within th ...

, while Garcia considered the galaxy to be a member of the LGG 334 group, along with NGC 5005 and NGC 5033.

References

External links

{{Catalogs, IC=4182, UGC=8188 Magellanic spiral galaxies Unbarred spiral galaxies Canes Venatici M94 Group 4182 08188 +09-18-055 045314 Discoveries by Max Wolf 19030321 F13035+3752