Pisces is one of the twelve zodiac constellations, and it is located in the northern celestial hemisphere. It is among the largest constellation in the sky, being the 14th largest out of the 88 modern constellations.
Key Facts & Summary
- The constellation of Pisces was among the first 48 constellations listed by the Greco-Roman astronomer Ptolemy, in his 2nd century Almagest.
- Today, Pisces is among the 88 modern constellations and it is the 14th largest in the sky, spreading for around 889 square degrees.
- Pisces is the Latin plural for “fish”, and the constellation itself is associated with the myth of Aphrodite and her son Eros, who were either rescued by two fishes, or they shape-shifted into fishes to flee from the monster Typhon.
- The constellation of Pisces contains only one Messier object, the spiral galaxy Messier 74.
- There is also only one major meteor shower associated with Pisces, the Piscids.
- The brightest star in Pisces is the G-type evolved giant star, Alpherg. This star has an apparent magnitude of +3.611.
- Alpherg also has a companion star orbiting it, a young star of magnitude 7.51.
- Currently, there are around 13 confirmed stars in Pisces that host planets.
- Some other interesting stars in Pisces, apart from its brightest star, are Van Maanen’s star, Alrescha, Fumalsamakah, Delta Piscium, Epsilon Piscium, Revati, Torcular, Omega Piscium, and Gamma Piscium, among many others.
- The constellation of Pisces also hosts some interesting deep-sky objects, apart from the aforementioned Messier object, they are the colliding galaxies NGC 520, the spiral galaxy NGC 488, the CL 0024+1654 galaxy cluster, the radio galaxy 3C 31, the Pisces Dwarf Galaxy, or the CGCG 436-030 spiral galaxy, among many others.
- The best time to view stars and deep-sky objects in Pisces is during November.
The constellation of Pisces originates from some composition of the Babylonian constellations Sinutu4 – the great swallow – in current western Pisces, and Anunitum – the Lady of the Heaven, - in the current northern fish.
Pisces is often associated with the Greek legend of Aphrodite and her son Eros, who either shape-shifted into forms of fishes to escape the monster Typhon sent by the Titans, or they were rescued by two fishes.
The Roman version of the story has Venus and Cupid – the Roman equivalents of Aphrodite and Eros – carried away from this danger on the backs of two fishes.
The constellation of Pisces is among the largest ones in the sky, occupying the 14th place in terms of size. Pisces spreads out for over 889 square degrees.
Pisces is located in the first quadrant of the northern hemisphere (NQ1) and can be seen at latitudes between +90o and -65o.
- Right Ascension: 1h
- Declination: +15o
- Visible: between +90o and -65o
- Best viewed: at 21:00 ( 9 p.m. ) during November
The neighboring constellations surrounding Pisces are Andromeda, Aquarius, Aries, Cetus, Pegasus, and Triangulum. Pisces belongs to the Zodiac family of constellations, along with Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpius, Sagittarius, Capricornus, and Aquarius.
The constellation of Pisces contains only one Messier object. It is the spiral galaxy designated as Messier 74.
Messier 74, also designates as NGC 628, or the Phantom Galaxy is a spiral galaxy situated at around 32 million light-years away from us. This galaxy has two clearly defined spiral arms, and it is estimated to have around 100 billion stars.
It is the brightest member of the M74 Group, a group of 5 -7 galaxies that also includes the peculiar spiral galaxy NGC 660, and a few irregular galaxies.
Messier 74 has an apparent magnitude of 10.0, and it has around 95,000 light-years in diameter. It is located at 1.5 degrees east-northeast of the brightest star in Pisces, Alpherg / Eta Piscium. This galaxy has the second-lowest surface brightness of all Messier objects, the lowest being Messier 101.
There are several interesting stars in Pisces, apart from its brightest star, they are the Van Maanen’s star, Alrescha, Fumalsamakah, Delta Piscium, Epsilon Piscium, Revati, Torcular, Omega Piscium, and Gamma Piscium, among many others. Currently, there are around 13 confirmed stars in Pisces that host planets.
The brightest star in Pisces is Eta Piscium – commonly known as Alpherg, a G-type evolved giant star that has an apparent magnitude of +3.611. Alpherg also has a companion star of magnitude 7.51.
Alpherg, designated as Eta Piscium, is a binary star located at around 350 light-years away from Earth. It is composed of an evolved G-type giant star, and a magnitude 7 companion.
Alpherg has a weak magnetic field, yet it has around 378% of our Sun’s mass, 2,648% of its radius, and it is 457 times brighter than our Sun. This star is cooler than our Sun, having temperatures of around 4,937 K.
Van Maanen’s Star
This star has an apparent magnitude of 12.374, it is quite faint. Van Maanen 2 has only 68% of our Sun’s mass, 1% of its radius, and it is 3 billion years old.
Alrescha, designated as Alpha Piscium, is a binary star system located at around 151 light-years away from us. It has a combined apparent magnitude of 3.82.
The primary component, designated as A, has an apparent magnitude of +4.33, and it is 32 times brighter than our Sun, having 230% of our Sun’s mass, and a rotational velocity of 81 km / 50.3 mi per second.
The secondary component, designated as B, has an apparent magnitude of 5.23, and it is 12 times brighter than our Sun, having 180% of our Sun’s mass, and a rotational velocity of 84 km / 52.1 mi per second.
Delta Piscium is an orange-hued evolved K-type giant star, located at around 311 light-years away from us. It has an apparent magnitude of +4.416, thus it is visible to the naked eye.
Delta Piscium has 165% of our Sun’s mass, 4,400% of its radius, and it is 447 times brighter than our Sun. This star is younger than our Sun, and cooler, having temperatures of around 3,963 K.
Epsilon Piscium is a yellow-orange hued star located at around 182 light-years away from us. It has an apparent magnitude of 4.27. This star is 67.6 times brighter than our Sun.
Epsilon Piscium has around 227% of our Sun’s mass, 1,090% of its radius, and it is cooler than our Sun, having temperatures of around 4,814 K.
Revati, designated as Zeta Piscium, is a quintuple star system located at around 170 light-years away from us. This system is composed of a binary star – Zeta Piscium A – that has a combined apparent magnitude of 5.28, and a triple star system – Zeta Piscium BC – at magnitude 6.43.
The primary star, named Revati, is an A-type subgiant star that has around 207% of our Sun’s mass, it is 27.4 times more luminous, and it is hotter than our Sun, having temperatures of around 7,345 K. This star is also a fast-spinner, having a rotational velocity of around 196 km / 121.7 mi per second.
Torcular, designated as Omicron Piscium, is a binary star system located at around 280 light-years away from us. The two stars have a combined apparent magnitude of 4.27.
This binary star system is a member of the thin disk population of the Milky Way. The primary star, known as Torcular, is an evolved K-type giant star that has around 303% of our Sun’s mass.
Torcular is 132 times brighter than our Sun, and it has 1,457% of its radius. This star is cooler than our Sun and younger. It is estimated that Torcular is only 390 million years old.
Omega Piscium, also known as Cauda Piscis, is a subgiant star located at around 104.3 light-years away from us. It has an apparent magnitude of 4.01.
This star has around 122% of our Sun’s mass, and it is 21 times brighter. Omega Piscium is also hotter than our Sun, having temperatures of around 6,641 K.
Gamma Piscium is a yellow K-type giant star located at around 138 light-years away from us. It has an apparent magnitude of 3.699. It is the second-brightest star in Pisces.
Gamma Piscium has around 111% of our Sun’s mass, 1,128% of its radius, and it is 62.7 times brighter than our Sun.
Nu Piscium is an orange-hued binary star system located at around 353 light-years away from us. It has an apparent magnitude of 4.44. The primary star is an evolved K-type giant star.
Nu Piscium is also classified as a barium star, indicating that the atmosphere was previously enriched by accretion of s-process elements from what is now a white dwarf companion.
This star has around 166% of our Sun’s mass, 3,400% of its radius, and it is 380 times brighter than our Sun. Nu Piscium is estimated to be 3.41 billion years old, thus it is younger than our Sun.
19 Piscium, also designated as TX Piscium, is a variable carbon star, being among the reddest naked eye stars. It is located at around 900 light-years away and it has an apparent magnitude that varies from 4.79 to 5.20.
19 Piscium has between 100% and 300% of our Sun’s mass, 29,500% of its radius, and it is more than 7,019 times brighter than our Sun.
54 Piscium is an orange dwarf star located at around 36 light-years away from us. It has an apparent magnitude of 5.88, and it also hosts an extrasolar planet, and a brown dwarf.
54 Piscium has only 76% of our Sun’s mass, 94% of its radius, and it is only half as bright. This star is also cooler than our Sun, having temperatures of around 5,062 K.
The exoplanet orbits its parent star at a separation of 0.28 AU. The brown dwarf in this system has only 5% of our Sun’s mass, 8% of its radius, and its surface temperatures have been recorded at a mere 810 K.
The constellation of Pisces hosts some interesting deep-sky objects. Apart from the aforementioned Messier object, they are the colliding galaxies NGC 520, the spiral galaxy NGC 488, the CL 0024+1654 galaxy cluster, the radio galaxy 3C 31, the Pisces Dwarf Galaxy, or the CGCG 436-030 spiral galaxy, among many others.
CL 0024+1654 is a large galaxy cluster located at around 3.6 billion light-years away from us. It is composed of many yellow elliptical and spiral galaxies.
The cluster lenses a galaxy located behind it, which results in arc-like images of the galaxy in the background. The galaxy behind this cluster is located at around 5.7 billion light-years away.
3C 31, also designated as NGC 383, is an active double radio source galaxy situated at around 237 million light-years away. This galaxy has an apparent magnitude of 13.4, and it hosts a supermassive black hole at its center.
CGCG436-030, also designated as PGC 4798, is a spiral galaxy located at around 400 million light-years away from us. It has an apparent magnitude of 14.9.
The Pisces Dwarf is an irregular dwarf galaxy that is part of the Local Group of galaxies, and it is suspected of being a satellite galaxy of the Triangulum Galaxy / M33.
The Pisces Dwarf is approaching our Milky Way at a radial velocity of around 287 km / 178.3 mi per second. This galaxy is located at around 2.51 million light-years away from us. It has an apparent magnitude of 14.2, and it is mostly populated by old stars.
Arp 284 is a pair of interacting galaxies, which are designated as NGC 7714, and NGC 7715. NGC 7714 is a spiral galaxy, while NGC 7715 is of uncertain type, probably an edge-on spiral or an irregular galaxy. Arp 284 has an apparent magnitude of 12.2.
NGC 474 is an elliptical galaxy located at around 100 million light-years away from us. This galaxy is bigger than our Milky Way, having 250,000 light-years in diameter. It is known to possess tidal tails, although their origins remain unknown.
NGC 520 is a pair of colliding spiral galaxies located at around 105 million light-years away from us. It has an apparent magnitude of 12.2. Simulations suggest that the merging process began 300 million years ago, and it is still ongoing.
NGC 60 is a spiral galaxy with unusually distorted spiral arms. This event is usually caused by interaction with other galaxies, however, there are none near NGC 60.
NGC 60 is located at around 500 million light-years away from us, and it has an apparent magnitude of 14.85.
NGC 514 is a low-luminosity, intermediate spiral galaxy located at around 82.8 million light-years away from us. It has an apparent magnitude of 11.65.
NGC 488 is a face-on spiral galaxy located at around 98.3 million light-years away from us. It has an apparent magnitude of 10.4, and a diameter of around 171,000 light-years.
The constellation of Pisces is associated with only one meteor shower, the Piscids. The Piscids occur during September and October, with their peak being around the 8th of September, the 21st of September, and on October 13. Around 10 meteors can be seen per hour. This meteor shower is slow and sometimes comparatively long-lasting.
Pisces is located near Aquarius and Aries. While the astrological sign Pisces per definition runs from ecliptical longitude 330o to 0, this position is now mostly covered by the constellation of Aquarius, due to the precession from when the constellation and the sign roughly coincided.
Did you know?
- The ancient Babylonians called a part of Pisces – DU.NU.NU – the fish cord, or ribbon, as evidenced in the first-millennium BC texts known as the Astronomical Diaries.
- The constellation of Pisces is associated with the German legend of Antenteh, who owned just a tub and a crude cabin when he met a magical fish. They offered him a wish, which he refused, however, his wife persuades him to return to the fish and ask for a beautifully furnished home. They granted this wish, but his wife was not satisfied. She then asked to be a queen and have a palace, and this wish was granted. The wife then wanted to become a goddess, but the fish became angry and took the palace and home, leaving the couple with the tub and cabin once again. The tub in this story is sometimes recognized as the Great Square of Pegasus.
- The stars in Pisces were incorporated into several Chinese constellations, such as Wai-ping, or Koui-siou.