1 Lyncis is a single star in the northern

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 ...

Lynx A lynx is a type of wild cat. Lynx may also refer to: Astronomy * Lynx (constellation) * Lynx (Chinese astronomy) * Lynx X-ray Observatory, a NASA-funded mission concept for a next-generation X-ray space observatory Places Canada * Lynx, Ontar ...

. It is also known by its variable star designation of UW Lyncis; ''1 Lyncis'' is the Flamsteed designation. This object is visible to the naked eye as a faint, reddish-hued star with an apparent visual magnitude of 4.95. It is moving further from the Earth with a heliocentric

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. The star 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 ...

of spectral type M3IIIab, currently 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 ...

, having exhausted the hydrogen at its core and evolved away from the

main sequence In astronomy, the main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Her ...

. It has been classified as a possible slow irregular variable, after being found to be slightly variable in 1969 by

Olin J. Eggen Olin Jeuck Eggen (July 9, 1919 – October 2, 1998) was an American astronomer. Biography Olin Jeuck Eggen was born to Olin Eggen and Bertha Clare Jeuck in the village of Orfordville in Rock County, Wisconsin. Both of his parents were of Norw ...

. Its changes in brightness are complex, with two shorter changeable periods of 35–40 and 47–50 days due to the star's pulsations, and a longer period of 1,500 days possibly due to the star's rotation or convectively induced oscillatory thermal (COT) mode. The star has expanded to 156 times the Sun's radius and it is radiating 2,848 times the luminosity of the Sun from its enlarged

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 3,485 K.

References

{{DEFAULTSORT:1 Lyncis M-type giants Asymptotic-giant-branch stars Slow irregular variables Lynx (constellation) BD+61 0869 Lyncis, 01 042973 029919 2215 Lyncis, UW