V445

V445 is not a single object but a designation used in the astronomical naming of variable stars. The label follows the convention of assigning a sequential V-number to variable stars within a given constellation. As a result, V445 can refer to more than one distinct star, each with its own set of properties and variability type. The best-known examples are V445 Puppis and V445 Lyr, among potentially others in different constellations.

V445 Puppis is a nova located in the southern constellation Puppis. It erupted around 2000 and is notable for its unusual spectral characteristics: its outburst spectra are dominated by helium and carbon lines with little to no hydrogen detected. This led to the interpretation of V445 Puppis as a helium nova, a thermonuclear explosion on a white dwarf accreting helium from a companion. The eruption was accompanied by dust formation, and the object faded over subsequent years, highlighting the diversity of nova phenomena beyond hydrogen-rich explosions.

V445 Lyr is a RR Lyrae-type variable star in the constellation Lyra observed by the Kepler space telescope. It is distinguished by a complex Blazhko modulation, with multiple amplitude and phase variation periods. Kepler data provided detailed light curves that have contributed to the study of pulsation modes and the Blazhko effect in RR Lyrae stars.

In summary, V445 refers to multiple variable stars, each with distinct astrophysical significance. The designation is a cataloging label rather than a reference to a single object, underscoring the diversity within variable-star studies.