* Astronomy

R Lyncis (R Lyn and HD 51610) is a red giant variable star located about 2800 - 3100 light years away in the constellation of Lynx. R Lyncis varies in brightness between magnitude +7.2 and +14.3 over a period of 378.75 days.

Lyncis R (also R Lyn, HD 51610 and HIP 33824) is a long-period variable star located 3,100 light-years away in the constellation Lynx.
R Lyncis is a S-type red giant star whose spectrum is dominated by oxides of metals, similar to class K5-M giant stars but that shows the presence of zirconium oxide. Another feature of this class of stars is the stellar mass loss, which in the case of R Lyncis is estimated at ~3.5 x 10^-7 times the solar mass per year. Also, R Lyncis is a very bright star, between 5600 and 9300 times as luminous as the Sun.
Various measurements of its angular diameter by interferometry give the star a value of between 5.23 and 6.10 milliarcseconds, corresponding to an actual diameter of roughly 550 solar radii.
Lyncis R is a Mira Variable whose brightness varies from magnitude +7.2 and +14.3 over a period of 378.75 days. The variability comes from pulsations in the stellar surface, causing changes in colour and brightness.
However, S-type stars are generally redder than their K- or M-type counterparts of the same photospheric temperature.

Adapted from Source

Maxima of the Variable Star R Lyncis on the 19th August, 2012.

Magnitude range: 7.2 - 14.3
Period: 378.8 days 
Type: Mira

Position(2000):  RA=07 01 18.00769 | Dec= +55 19 49.7553