Tau1 Aquarii


Tau1 Aquarii, Latinized from τ1 Aquarii, is the Bayer designation for a star in the equatorial constellation of Aquarius. With an apparent visual magnitude of 5.66, it is a faint naked eye that requires dark suburban skies for viewing. Parallax measurements made during the Hipparcos mission yield a distance estimate of roughly from Earth.
τ1 Aquarii has a stellar classification of B9 V; right along the borderline between a B- and A-type main sequence star. It is around 100 million years old and has twice the Sun's radius. When examined in the infrared band, it displays an excess emission that is a characteristic of stars with an orbiting debris disk. The model that best fits the data suggests there are two concentric circumstellar disks.