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Abstract We present individual star formation histories (SFHs) of ∼3000 massive galaxies (log(M_*/M_⊙) > 10.5) from the Large Early Galaxy Astrophysics Census spectroscopic survey at a lookback time of ∼7 billion yr and quantify the population trends leveraging 20 hr deep-integrated spectra of these ∼1800 star-forming and ∼1200 quiescent galaxies at 0.6 <z< 1.0. Essentially all galaxies at this epoch contain stars of age <3 Gyr, in contrast with older massive galaxies today, facilitating better recovery of previous generations of star formation at cosmic noon and earlier. We conduct spectrophotometric analysis using parametric and nonparametric Bayesian stellar population synthesis modeling tools—BagpipesandProspector—to constrain the median SFHs of this mass complete sample and characterize population trends. A consistent picture arises for the late-time stellar mass growth when quantified ast₅₀andt₉₀, corresponding to the age of the Universe when galaxies formed 50% and 90% of their total stellar mass, although the two methods disagree at the earliest formation times (e.g.,t₁₀). Our results reveal trends in both stellar mass and stellar velocity dispersion as in the local Universe—low-mass galaxies with shallower potential wells grow their stellar masses later in cosmic history compared to high-mass galaxies. Unlike local quiescent galaxies, the median duration of late-time star formation (τ_SF,late=t₉₀–t₅₀) does not consistently depend on the stellar mass. This census sets a benchmark for future deep spectrophotometric studies of the more distant Universe. 

We present new JWST observations of the nearby, prototypical edge-on, spiral galaxy NGC 891. The northern half of the disk was observed with NIRCam in its F150W and F277W filters. Absorption is clearly visible in the mid-plane of the F150W image, along with vertical dusty plumes that closely resemble the ones seen in the optical. A ∼10 × 3 kpc²area of the lower circumgalactic medium (CGM) was mapped with MIRI F770W at 12 pc scales. Thanks to the sensitivity and resolution of JWST, we detect dust emission out to ∼4 kpc from the disk, in the form of filaments, arcs, and super-bubbles. Some of these filaments can be traced back to regions with recent star formation activity, suggesting that feedback-driven galactic winds play an important role in regulating baryonic cycling. The presence of dust at these altitudes raises questions about the transport mechanisms at play and suggests that small dust grains are able to survive for several tens of million years after having been ejected by galactic winds in the disk-halo interface. We lay out several scenarios that could explain this emission: dust grains may be shielded in the outer layers of cool dense clouds expelled from the galaxy disk, and/or the emission comes from the mixing layers around these cool clumps where material from the hot gas is able to cool down and mix with these cool cloudlets. This first set of data and upcoming spectroscopy will be very helpful to understand the survival of dust grains in energetic environments, and their contribution to recycling baryonic material in the mid-plane of galaxies.