JWST Discovers Ten Early Galaxies in the Cosmic Web
Astronomers using the James Webb Space Telescope (JWST) have made a groundbreaking discovery of ten galaxies that make up an early version of the cosmic web, just 830 million years after the Big Bang. The cosmic web is the large-scale structure of the Universe, consisting of filaments and voids that have formed over time.
The cosmic web started as density fluctuations in the early Universe, with matter condensing into knots at the intersections of gas sheets and filaments. These knots and filaments hosted the formation of the first stars and galaxies. By studying the early versions of the cosmic web, astronomers can gain insights into the early evolution of the Universe.
The ten galaxies discovered by the JWST are aligned in a thin, three million light-year-long thread, anchored by a bright quasar. This filamentary structure is one of the earliest ever found associated with a distant quasar. The size and place in cosmic history of this structure have surprised astronomers.
The discovery was made as part of the ASPIRE observation program, which aims to study the formation of the earliest galaxies and black holes in the Universe, as well as the enrichment of the early universe with heavier elements and the epoch of reionization. The ASPIRE program uses both images and spectra of 25 quasars that existed during the early stages of the Universe.
At least eight of the quasars studied in the ASPIRE program have black holes that formed less than a billion years after the Big Bang. These black holes are incredibly massive, with masses between 600 million to 2 billion times that of the Sun. The rapid growth of these black holes raises questions about their formation and fuel sources.
To grow as quickly as observed, these black holes needed a large fuel source. Their host galaxies were also massive, indicating a connection between the black holes and the surrounding galaxies. The outflows from these black holes can suppress star formation in their host galaxies and were observed in the early universe for the first time.
Studying the early universe and the cosmic web is crucial for understanding the origin and evolution of the Universe. The ASPIRE program aims to incorporate the emergence of the earliest massive black holes into the current understanding of cosmic structure.
The Epoch of Reionization, during which the first stars and galaxies formed, is a particularly interesting period for astronomers. The JWST observations provide insights into this epoch, including the formation of the first neutral atoms of gas and the subsequent heating by the first stars. The discoveries made during the ASPIRE program will contribute to a better understanding of the formation of supermassive black holes in the early Universe and the feedback between galaxy formation and black hole creation.
As the JWST continues to observe the early Universe, astronomers expect to uncover more fragments of the cosmic web and gain valuable insights into the evolution of the Universe from its earliest stages.