Neutrinos are produced during stellar evolution by means of thermal and thermonuclear processes. We model the cumulative neutrino flux expected at Earth from all stars in the Milky Way: the Galactic stellar neutrino flux ($\mathrm{GS}\nu \mathrm{F}$). We account for the star formation history of our Galaxy and reconstruct the spatial distribution of Galactic stars by means of a random sampling procedure based on Gaia Data Release 2. We use the stellar evolution code mesa to compute the neutrino emission for a suite of stellar models with solar metallicity and zero-age-main-sequence mass between $0.08M_{\odot }$ and $100M_{\odot }$, from their premain sequence phase to their final fates. We then reconstruct the evolution of the neutrino spectral energy distribution for each stellar model in our suite. The $\mathrm{GS}\nu \mathrm{F}$ lies between $\mathcal{O}(1)\mathrm{keV}$ and $\mathcal{O}(10)\mathrm{MeV}$, with thermal (thermonuclear) processes responsible for shaping neutrino emission at energies smaller (larger) than 0.1 MeV. Stars with mass larger than $\mathcal{O}(1M_{\odot })$, located in the thin disk of the Galaxy, provide the largest contribution to the $\mathrm{GS}\nu \mathrm{F}$. Moreover, most of the $\mathrm{GS}\nu \mathrm{F}$ originates from stars distant from Earth about 5–10 kpc, implying that a large fraction of stellar neutrinos can reach us from the Galactic Center. Solar neutrinos and the diffuse supernova neutrino background have energies comparable to those of the $\mathrm{GS}\nu \mathrm{F}$, challenging the detection of the latter. However, directional information of solar neutrino and $\mathrm{GS}\nu \mathrm{F}$ events, together with the annual modulation of the solar neutrino flux, could facilitate the $\mathrm{GS}\nu \mathrm{F}$ detection; this will kick off a new era for low-energy neutrino astronomy, also providing a novel probe to discover new physics.

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• Extrasolar neutrino astronomy
• Formation & evolution of stars & galaxies
• Particle astrophysics
• Neutrinos
• Stars
• Neutrino detection