We present a study of the double-lined spectroscopic binary HD 21278 in the young Alpha Persei open cluster. HD 21278 was chosen for this project because the primary star in the binary is rapidly evolving. This means the characteristics of the star are changing, which makes it easier to get a precise age estimate as long as its mass is known. We analyzed new spectroscopic data from the Nordic Optical Telescope and reanalyzed archived KPNO spectra to derive precise radial velocities for the binary. Interferometric data was taken using the CHARA Array at Mount Wilson to measure the sky positions of the two stars and the angle of inclination of the approximately 2 milliarcsecond orbit. Using the radial velocities and the inclination angle, we determine the masses of the two stars to be 4.526 土 0.070 M and 2.818 土 0.063 M and, using the masses, we find the age to be 101土6 Myrs. Since all stars that were born in the cluster were born at the same time, the age for the binary can be applied to any stars that were also born in the cluster. Finally, we will use the age estimates to revisit calculations of the initial masses of the massive white dwarfs thought to be escapees from the Alpha Persei cluster. This is interesting because the white dwarfs are near the maximum mass that white dwarfs can have, and will tell us about the threshold between stars that become supernovae and stars that become white dwarfs.
