Abstract: The cerebral cortex is comprised of properly localized cell types that exert their specific functions. In the developing brain, cells migrate from the germinal region to their functional locations (Silva et al., 2019; Cossart and Garel, 2022). For example, neocortical excitatory neurons are generated in the cerebral ventricular and subventricular zones, move to the developing cortical plate via radial migration, and reside in a radial array of six neuronal layers (Oishi and Nakajima, 2018). On the other hand, cortical interneurons are mainly generated in ganglionic eminences, migrate tangentially across the cerebral cortex, and reach their final destinations in the cortex (Lim et al., 2018). The failure of neuronal migration leads to defects in cortical layer formation. While the mechanisms of neuronal distribution have been well examined, how astrocytes are diffusely distributed in the cortex is still unclear. Astrocytes are glial cells in the cerebral cortex with several functions, including metabolic support and synapse formation (Abbott et al., 2006; Bosworth and Allen, 2017; Allen and Lyons, 2018). For example, astrocytes establish synaptic connectivity in the developing brain while they contact numerous synapses and maintain optimal neuronal activity in the adult brain. In the developing brain, astrocytes are primarily generated from radial glia after the neurogenic period. While a certain type of astrocyte called fibrous astrocytes populates the white matter, protoplasmic astrocytes migrate to the cortical plate during neural network formation.