Sculptor is a small and faint constellation in the southern sky. It represents a

sculptor Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable ...

. It was introduced by

Nicolas Louis de Lacaille Abbé Nicolas-Louis de Lacaille (; 15 March 171321 March 1762), formerly sometimes spelled de la Caille, was a French astronomer and geodesist who named 14 out of the 88 constellations. From 1750 to 1754, he studied the sky at the Cape of Good ...

in the 18th century. He originally named it Apparatus Sculptoris (the sculptor's studio), but the name was later shortened.

History

The region to the south of Cetus and Aquarius had been named by

Aratus Aratus (; grc-gre, Ἄρατος ὁ Σολεύς; c. 315 BC/310 BC240) was a Greek didactic poet. His major extant work is his hexameter poem ''Phenomena'' ( grc-gre, Φαινόμενα, ''Phainómena'', "Appearances"; la, Phaenomena), the ...

in 270 BC as ''The Waters'' – an area of scattered faint stars with two brighter stars standing out. Professor of astronomy

Bradley Schaefer Bradley Elliott Schaefer is a professor of astronomy and astrophysics at Louisiana State University. He received his PhD from the Massachusetts Institute of Technology in 1983. Early life In addition to his academic pursuits, Schaefer is rem ...

has proposed that these stars were most likely Alpha and Delta Sculptoris. The French astronomer

Nicolas-Louis de Lacaille Abbé Nicolas-Louis de Lacaille (; 15 March 171321 March 1762), formerly sometimes spelled de la Caille, was a French astronomer and geodesist who named 14 out of the 88 constellations. From 1750 to 1754, he studied the sky at the Cape of Good ...

first described the constellation in French as ''l'Atelier du Sculpteur'' (the sculptor's studio) in 1751–52, depicting a three-legged table with a carved head on it, and an artist's mallet and two chisels on a block of marble alongside it. De Lacaille had observed and catalogued almost 10,000 southern stars during a two-year stay at the

Cape of Good Hope The Cape of Good Hope ( af, Kaap die Goeie Hoop ) ;''Kaap'' in isolation: pt, Cabo da Boa Esperança is a rocky headland on the Atlantic coast of the Cape Peninsula in South Africa. A common misconception is that the Cape of Good Hope is ...

, devising fourteen new constellations in uncharted regions of the

Southern Celestial Hemisphere The southern celestial hemisphere, also called the Southern Sky, is the southern half of the celestial sphere; that is, it lies south of the celestial equator. This arbitrary sphere, on which seemingly fixed stars form constellations, appear ...

not visible from Europe. He named all but one in honour of instruments that symbolised the

Age of Enlightenment The Age of Enlightenment or the Enlightenment; german: Aufklärung, "Enlightenment"; it, L'Illuminismo, "Enlightenment"; pl, Oświecenie, "Enlightenment"; pt, Iluminismo, "Enlightenment"; es, La Ilustración, "Enlightenment" was an intel ...

Characteristics

Sculptor is a small constellation bordered by Aquarius and

Cetus Cetus () is a constellation, sometimes called 'the whale' in English. The Cetus was a sea monster in Greek mythology which both Perseus and Heracles needed to slay. Cetus is in the region of the sky that contains other water-related conste ...

to the north,

Fornax Fornax () is a constellation in the southern celestial hemisphere, partly ringed by the celestial river Eridanus. Its name is Latin for furnace. It was named by French astronomer Nicolas Louis de Lacaille in 1756. Fornax is one of the 88 mod ...

to the east, Phoenix to the south, Grus to the southwest, and

Piscis Austrinus Piscis Austrinus is a constellation in the southern celestial hemisphere. The name is Latin for "the southern fish", in contrast with the larger constellation Pisces, which represents a pair of fish. Before the 20th century, it was also known a ...

to the west. The bright star

Fomalhaut Fomalhaut is the brightest star in the southern constellation of Piscis Austrinus, the "Southern Fish", and one of the brightest stars in the night sky. It has the Bayer designation Alpha Piscis Austrini, which is Latinized from � ...

is nearby. The three-letter abbreviation for the constellation, as adopted by the

International Astronomical Union The International Astronomical Union (IAU; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach ...

in 1922, is "Scl". The official constellation boundaries, as set by Belgian astronomer Eugène Delporte in 1930, are defined by a polygon of 6 segments. In the

equatorial coordinate system The equatorial coordinate system is a celestial coordinate system widely used to specify the positions of celestial objects. It may be implemented in spherical or rectangular coordinates, both defined by an origin at the centre of Earth, a fun ...

, the

right ascension Right ascension (abbreviated RA; symbol ) is the angular distance of a particular point measured eastward along the celestial equator from the Sun at the March equinox to the ( hour circle of the) point in question above the earth. When pai ...

coordinates of these borders lie between and , while the

declination In astronomy, declination (abbreviated dec; symbol ''δ'') is one of the two angles that locate a point on the celestial sphere in the equatorial coordinate system, the other being hour angle. Declination's angle is measured north or south of t ...

coordinates are between −24.80° and −39.37°. The whole constellation is visible to observers south of latitude 50°N.

Notable features

Stars

No stars brighter than 3rd magnitude are located in Sculptor. This is explained by the fact that Sculptor contains the

south galactic pole The galactic coordinate system is a celestial coordinate system in spherical coordinates, with the Sun as its center, the primary direction aligned with the approximate center of the Milky Way Galaxy, and the fundamental plane parallel to an ap ...

where stellar density is very low. Overall, there are 56 stars within the constellation's borders brighter than or equal to

apparent magnitude Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's li ...

6.5. The brightest star is

Alpha Sculptoris Alpha Sculptoris, Latinized from α Sculptoris, is the Bayer designation for a blue-white star in the southern constellation of Sculptor. It has an apparent visual magnitude of +4.30, which makes it the brightest star in this generally f ...

, an SX Arietis-type

variable star A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are classified as e ...

with a spectral type B7IIIp and an apparent magnitude of 4.3. It is 780 ± 30 light-years distant from Earth.

Eta Sculptoris Eta Sculptoris, Latinized from η Sculptoris, is a single, variable star in the central part of the southern constellation of Sculptor. It is visible to the naked eye as a faint, red-hued star with an apparent visual magnitude that fl ...

is a

red giant A red giant is a luminous giant star of low or intermediate mass (roughly 0.3–8 solar masses ()) in a late phase of stellar evolution. The outer atmosphere is inflated and tenuous, making the radius large and the surface temperature around or ...

of spectral type M4III that varies between magnitudes 4.8 and 4.9, pulsating with multiple periods of 22.7, 23.5, 24.6, 47.3, 128.7 and 158.7 days. Estimated to be around 1,082 times as luminous as the Sun,Vizier catalog entry
/ref> it is 460 ± 20 light-years distant from Earth.

R Sculptoris R Sculptoris is a variable star system in the southern constellation of Sculptor. Parallax measurements provide a distance estimate of approximately from the Sun. An independent estimate based on measurements of an ejected shell surr ...

is a red giant that has been found to be surrounded by spirals of matter likely ejected around 1800 years ago. It is 1,440 ± 90 light-years distant from Earth. The

Astronomical Society of Southern Africa The Astronomical Society of Southern Africa (ASSA), formed in 1922, is a widespread body consisting of both amateur and professional astronomers. There are eight autonomous centres throughout Southern Africa. History The Cape Astronomical Associ ...

in 2003 reported that observations of the

Mira variable Mira variables (named for the prototype star Mira) are a class of pulsating stars characterized by very red colours, pulsation periods longer than 100 days, and amplitudes greater than one magnitude in infrared and 2.5 magnitude at visual wave ...

stars T, U, V and

X Sculptoris X, or x, is the twenty-fourth and third-to-last letter in the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''"ex"'' (pronounced ), ...

were very urgently needed as data on their light curves was incomplete.

Deep sky objects

The constellation also contains the Sculptor Dwarf, a

dwarf galaxy A dwarf galaxy is a small galaxy composed of about 1000 up to several billion stars, as compared to the Milky Way's 200–400 billion stars. The Large Magellanic Cloud, which closely orbits the Milky Way and contains over 30 billion stars, is s ...

which is a member of the

Local Group The Local Group is the galaxy group that includes the Milky Way. It has a total diameter of roughly , and a total mass of the order of . It consists of two collections of galaxies in a "dumbbell" shape: the Milky Way and its satellites form ...

, as well as the Sculptor Group, the group of galaxies closest to the Local Group. The

Sculptor Galaxy The Sculptor Galaxy (also known as the Silver Coin, Silver Dollar Galaxy, NGC 253, or Caldwell 65) is an intermediate spiral galaxy in the constellation Sculptor. The Sculptor Galaxy is a starburst galaxy, which means that it is currently under ...

(NGC 253), a

barred spiral galaxy A barred spiral galaxy is a spiral galaxy with a central bar-shaped structure composed of stars. Bars are found in about two thirds of all spiral galaxies, and generally affect both the motions of stars and interstellar gas within spiral galaxies ...

and the largest member of the group, lies near the border between Sculptor and

. Another prominent member of the group is the

irregular galaxy 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 appearanc ...

NGC 55. One unique galaxy in Sculptor is the Cartwheel Galaxy, at a distance of 500 million

light-years A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 101 ...

. The result of a

merger Mergers and acquisitions (M&A) are business transactions in which the ownership of companies, other business organizations, or their operating units are transferred to or consolidated with another company or business organization. As an aspect ...

around 300 million years ago, the Cartwheel Galaxy has a core of older, yellow stars, and an outer ring of younger, blue stars, which has a diameter of 100,000 light-years. The smaller galaxy in the collision is now incorporated into the core, after moving from a distance of 250,000 light-years. The shock waves from the collision sparked extensive

star formation Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as "stellar nurseries" or "star-forming regions", collapse and form stars. As a branch of astronomy, star formation includ ...

in the outer ring.

Namesakes

''Sculptor'' (AK-103) was a

United States Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...

Crater class cargo ship The ''Crater''-class cargo ship were converted EC2-S-C1 type, Liberty cargo ships, constructed by the United States Maritime Commission (USMC) for use by the US Navy during World War II. The designation 'EC2-S-C1': 'EC' for Emergency Cargo, '2' fo ...

named after the constellation.

References

Notes Citations Sources * *

External links

The Deep Photographic Guide to the Constellations: Sculptor

{{DEFAULTSORT:Sculptor (Constellation) Southern constellations Constellations listed by Lacaille