VZ Camelopardalis is a single, variable star in the northern circumpolar constellation of

Camelopardalis Camelopardalis is a large but faint constellation of the northern sky representing a giraffe. The constellation was introduced in 1612 or 1613 by Petrus Plancius. Some older astronomy books give Camelopardalus or Camelopardus as alternative for ...

. It has a reddish hue and is faintly visible to the naked eye with an apparent visual magnitude that fluctuates around 4.92. The star is located at a distance of approximately 500

light year 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 1012 ...

s from the Sun based on

parallax Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight and is measured by the angle or semi-angle of inclination between those two lines. Due to foreshortening, nearby objects ...

, and is drifting further away with a

radial velocity The radial velocity or line-of-sight velocity, also known as radial speed or range rate, of a target with respect to an observer is the temporal rate of change, rate of change of the distance or Slant range, range between the two points. It is e ...

of +12 km/s. It was considered a member of the

Hyades Supercluster The Hyades Stream (or Hyades moving group) is a large collection of scattered stars that also share a similar trajectory with the Hyades Cluster. In 1869, Richard A. Proctor observed that numerous stars at large distances from the Hyades share a ...

, but in 1990 this was brought into question. This object is an aging

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 ...

star on the

asymptotic giant branch The asymptotic giant branch (AGB) is a region of the Hertzsprung–Russell diagram populated by evolved cool luminous stars. This is a period of stellar evolution undertaken by all low- to intermediate-mass stars (about 0.5 to 8 solar masses) lat ...

with a

stellar classification In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction grati ...

of M4IIIa. Its variable nature was discovered by American astronomer J. Ashbrook in 1948. This is a suspected slow irregular variable of sub-type Lb that varies in visual magnitude from 4.80 down to 4.96. Long-term

photometry Photometry can refer to: * Photometry (optics), the science of measurement of visible light in terms of its perceived brightness to human vision * Photometry (astronomy), the measurement of the flux or intensity of an astronomical object's electrom ...

measurements suggest there are at least four pulsation periods ranging from 27.1 to 39.0 days. With the supply of hydrogen at its core exhausted the star has cooled and expanded until it has now reached 89 times the

radius of the Sun Solar radius is a unit of distance used to express the size of stars in astronomy relative to the Sun. The solar radius is usually defined as the radius to the layer in the Sun's photosphere where the optical depth equals 2/3: :1\,R_ = 6.957\t ...

. It is radiating 1,252 times the luminosity of the Sun from its

photosphere The photosphere is a star's outer shell from which light is radiated. The term itself is derived from Ancient Greek roots, φῶς, φωτός/''phos, photos'' meaning "light" and σφαῖρα/''sphaira'' meaning "sphere", in reference to it ...

at an

effective temperature The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation. Effective temperature is often used as an estimate of a body's surface temperature ...

of 3,641 K.

References

{{DEFAULTSORT:VZ Camelopardalis M-type giants Asymptotic-giant-branch stars Slow irregular variables Camelopardalis Durchmusterung objects 055966 036547,

2742 74 may refer to: * 74 (number) * one of the years 74 BC, AD 74, 1974, 2074 * The 74, an American nonprofit news website * Seventy-four (ship), a type of two-decked sailing ship See also * List of highways numbered A ''list'' is any set of item ...

Camelopardalis, VZ