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We confirm the reality of the recently discovered Milky Way stellar cluster$\textit{Gaia}$ 1 using spectra acquired with the HERMES and AAOmegaspectrographs of the Anglo-Australian Telescope. This cluster had beenpreviously undiscovered due to its close angular proximity to Sirius, thebrightest star in the sky at visual wavelengths. Our observations identified 41cluster members, and yielded an overall metallicity of [Fe/H]$=-0.13\pm0.13$and barycentric radial velocity of $v_r=58.30\pm0.22$ km/s. These kinematicsprovide a dynamical mass estimate of $12.9^{+4.6}_{-3.9}\times10^3$M$_{\odot}$. Isochrone fits to $\textit{Gaia}$, 2MASS, and Pan-STARRS1photometry indicate that $\textit{Gaia}$ 1 is an intermediate age ($\sim3$ Gyr)stellar cluster. Combining the spatial and kinematic data we calculate$\textit{Gaia}$ 1 has a circular orbit with a radius of about 12~kpc, but witha large out of plane motion: $z_\textrm{max}=1.1^{+0.4}_{-0.3}$ kpc. Clusterswith such orbits are unlikely to survive long due to the number of planepassages they would experience.

$\textit{Siriusly}$, a newly identified intermediate-age Milky Way stellar cluster: A spectroscopic study of $\textit{Gaia}$ 1