Messier 74 (also known as NGC 628 and Phantom Galaxy) is a large

spiral galaxy Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work ''The Realm of the Nebulae''equatorial Equatorial may refer to something related to: *Earth's equator **the tropics, the Earth's equatorial region **tropical climate *the Celestial equator ** equatorial orbit **equatorial coordinate system ** equatorial mount, of telescopes * equatorial ...

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The origins of the e ...

Pisces Pisces may refer to: * Pisces, an obsolete (because of land vertebrates) taxonomic superclass including all fish * Pisces (astrology), an astrological sign * Pisces (constellation), a constellation **Pisces Overdensity, an overdensity of stars in ...

. It is about 32 million light-years away from Earth. The galaxy contains two clearly defined

spiral arm Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work ''The Realm of the Nebulae''grand design spiral galaxy A grand design spiral galaxy is a type of spiral galaxy with prominent and well-defined spiral arms, as opposed to multi-arm and flocculent spirals which have subtler structural features. The spiral arms of a grand design galaxy extend clearly ar ...

. The galaxy's low surface brightness makes it the most difficult

Messier object The Messier objects are a set of 110 astronomical objects catalogued by the French astronomer Charles Messier in his ''Catalogue des Nébuleuses et des Amas d'Étoiles'' (''Catalogue of Nebulae and Star Clusters''). Because Messier was only int ...

for amateur astronomers to observe. Its relatively large angular (that is, apparent) size and the galaxy's face-on orientation make it an ideal object for professional astronomers who want to study

spiral arm Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work ''The Realm of the Nebulae''spiral density waves. It is estimated that M74 hosts about 100 billion stars.

Observation history

M74 was discovered by

Pierre Méchain Pierre François André Méchain (; 16 August 1744 – 20 September 1804) was a French astronomer and surveyor who, with Charles Messier, was a major contributor to the early study of deep-sky objects and comets. Life Pierre Méchain was born i ...

in 1780. He then communicated his discovery to

Charles Messier Charles Messier (; 26 June 1730 – 12 April 1817) was a French astronomer. He published an astronomical catalogue consisting of 110 nebulae and star clusters, which came to be known as the ''Messier objects''. Messier's purpose f ...

, who listed the galaxy in his

catalog Catalog or catalogue may refer to: *Cataloging **'emmy on the 'og **in science and technology ***Library catalog, a catalog of books and other media ****Union catalog, a combined library catalog describing the collections of a number of libraries ...

In July 2022, it was observed by the

James Webb Space Telescope The James Webb Space Telescope (JWST) is a space telescope which conducts infrared astronomy. As the largest optical telescope in space, its high resolution and sensitivity allow it to view objects too old, distant, or faint for the Hubble Spa ...

, not long after it began taking its first pictures and observations and soon astronomy image processor Judy Schmidt made images of it available.

Structure

M74 has two spiral arms that wind counterclockwise from the galaxy's center. The spiral arms widen as they get farther from M74's center, but one of the arms narrows and the end. The arms deviate slightly from a constant angle.

Supernovae

Three

supernovae A supernova is a powerful and luminous explosion of a star. It has the plural form supernovae or supernovas, and is abbreviated SN or SNe. This transient astronomical event occurs during the last evolutionary stages of a massive star or when a ...

are known to have taken place within it: SN 2002ap,

SN 2003gd SN 2003gd was a Type II-P supernova explosion in the spiral galaxy Messier 74, located in the constellation Pisces. SN 2003gd was discovered on 12 June 2003 by Robert Evans, using a 0.31m reflector, and its discovery was confirmed on 13 June 2003 ...

, and

SN 2013ej SN 2013ej is a Type II-P supernova in the nearby spiral galaxy Messier 74 (NGC 628). It was discovered by the Lick Observatory Supernova Search on July 25, 2013, with the 0.76 m Katzman Automatic Imaging Telescope, with pre-discovery images hav ...

(the numbers denote the year). The latter was bright as 10th magnitude when viewed from the surface of Earth, so visible from almost all modern telescopes in a good night sky. SN 2002ap was one of few Type Ic supernovae (which denotes

hypernova A hypernova (sometimes called a collapsar) is a very energetic supernova thought to result from an extreme core-collapse scenario. In this case, a massive star (>30 solar masses) collapses to form a rotating black hole emitting twin energetic je ...

e) recorded within 10 Mpc every century. This explosion has been used to test theories on the origins of others further away and theories on the emission by supernovae of

gamma ray burst In gamma-ray astronomy, gamma-ray bursts (GRBs) are immensely energetic explosions that have been observed in distant galaxies. They are the most energetic and luminous electromagnetic events since the Big Bang. Bursts can last from ten milli ...

s. SN 2003gd is a Type II-P supernova. Type II supernovae have known

luminosities Luminosity is an absolute measure of radiated electromagnetic power (light), the radiant power emitted by a light-emitting object over time. In astronomy, luminosity is the total amount of electromagnetic energy emitted per unit of time by a st ...

, so they can be used to accurately measure distances. The distance measured to M74 using SN 2003gd is 9.6 ± 2.8 Mpc, or 31 ± 9 million ly. For comparison, distances measured using the brightest supergiants are 7.7 ± 1.7 Mpc and 9.6 ± 2.2 Mpc. Ben Sugerman found a "light echo" – a later reflection of the explosion – associated with SN 2003gd. This is one of the few supernovae in which such a reflection has been found. This reflection appears to be from dust in a sheet-like cloud that lies in front of the supernova, and it can be used to determine the composition of the interstellar dust.

Galaxy group

This is the brightest member of the

M74 Group The M74 Group (also known as the ''NGC 628 Group'') is a small group of galaxies in the constellation Pisces. The face-on spiral galaxy M74 (NGC 628) is the brightest galaxy within the group. Other members include the peculiar spiral galax ...

, a group of 5 to 7 galaxies that also includes the peculiar

spiral galaxy Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work ''The Realm of the Nebulae''NGC 660 and a few

irregular galaxies An irregular galaxy is a galaxy that does not have a distinct regular shape, unlike a spiral or an elliptical galaxy. Irregular galaxies do not fall into any of the regular classes of the Hubble sequence, and they are often chaotic in appearance, ...

. Different group membership identification methods (ranging from a clear, to likely, to perhaps historic gravitational tie) identify several objects of the group in common, and a few galaxies whose exact status within such groupings is currently uncertain. M74 3

Suspected black hole

In 2005Chandra : Photo Album and details of observation: M74 : 22 Mar 05
/ref> the

Chandra X-ray Observatory The Chandra X-ray Observatory (CXO), previously known as the Advanced X-ray Astrophysics Facility (AXAF), is a Flagship-class space telescope launched aboard the during STS-93 by NASA on July 23, 1999. Chandra is sensitive to X-ray sources 1 ...

announced its observation of an

ultraluminous X-ray source An ultraluminous X-ray source (ULX) is an astronomical source of X-rays that is less luminous than an active galactic nucleus but is more consistently luminous than any known stellar process (over 1039 erg/s, or 1032 watts), assuming that it radiat ...

(ULX) in M74, radiating more X-ray power than a

neutron star A neutron star is the collapsed core of a massive supergiant star, which had a total mass of between 10 and 25 solar masses, possibly more if the star was especially metal-rich. Except for black holes and some hypothetical objects (e.g. white ...

, in periodic intervals of around two hours. It has an estimated mass of . This is an indicator of an

intermediate-mass black hole An intermediate-mass black hole (IMBH) is a class of black hole with mass in the range 102–105 solar masses: significantly more than stellar black holes but less than the 105–109 solar mass supermassive black holes. Several IMBH candidate obje ...

. This would be a rather uncommon class, in between in size of stellar black holes and the massive black holes theorized to be in the center of many galaxies. Such an object is believed to form from lesser ("stellar") black holes within a star cluster. The source has been given identification number CXOU J013651.1+154547.

Amateur astronomy observation

Messier 74 is 1.5° east-northeast of

Eta Piscium Eta Piscium (η Piscium, abbreviated Eta Psc, η Psc) is a binary star and the brightest point of light in the constellation of Pisces (constellation), Pisces with an apparent visual magnitude of +3.6. Based upon a measured annual stellar ...

. This galaxy has the second-lowest Earth-surface brightness of any Messier object. ( M101 has the lowest.) It requires a good night sky. This galaxy may be best viewed under low magnification; when highly magnified, the diffuse emission becomes more extended and appears too faint to be seen by many people. Additionally, M74 may be more easily seen when using averted vision when the eyes are fully dark adapted.

References and footnotes

External links

*
Spiral Galaxy M74 @ SEDS Messier pages
* {{Sky, 01, 36, 41.8, +, 15, 47, 01, 30000000 Unbarred spiral galaxies Messier 074 Messier 074 074 Messier 074 01149 05974 Astronomical objects discovered in 1780