 Hubble bubble (astronomy)

The term "Hubble bubble" refers to a large, somewhat spherical region of space that exhibits a lower density of galaxies and other cosmic structures compared to the surrounding universe. This phenomenon is associated with the Hubble Space Telescope and relates to the observation of cosmic expansion. In the context of cosmology, the Hubble bubble is typically discussed in relation to the Hubble flow, which describes how galaxies are observed to be moving away from each other as the universe expands.