Using a forward modeling approach based on the predictions of the data-calibrated NEFERTITI model for the Milky Way’s evolution, we uncover the expected properties of the progenitors of our Galaxy as observed by JWST. Our results show that the Firefly Sparkle system detected by JWST at redshift z = 8.3 is consistent with what we predict for a MW-like galaxy in its infancy.
Our novel approach, described in Rusta et al. 2024 ApJ Letter has allowed us to estimate the properties of the individual MW building blocks, which have physically motivated and complex evolutionary histories. We provide predictions for the number of detectable MW progenitors at various redshifts and for different magnification factors. Catching other MW-like systems at cosmic dawn will indeed allow the community to
collect different pictures of an MW analog during its infancy.