Newly Confirmed Early Galaxy Discovered James Webb Space Telescope

Summary: The James Webb Space Telescope (JWST) has confirmed the existence of one of the earliest galaxies known in the Universe. Dubbed Maisie’s Galaxy, the object was observed to have appeared just 390 million years after the Big Bang. This discovery not only indicates that the early Universe is more populated than previously thought, but it also emphasizes the need for careful analysis of JWST observations. The galaxy, named in honor of astronomer Steven Finkelstein’s daughter, marks one of the first distant galaxies identified the JWST that has been spectroscopically confirmed. By using redshift, a measure of the stretching of light caused the Universe’s expansion, astronomers can determine the time at which the light was emitted. LMaisies’s Galaxy was initially estimated to have a redshift of z~12, suggesting it was observed approximately 366 million years after the Big Bang. However, spectroscopic analysis using the JWST’s NIRSpec instrument later determined its redshift to be z=11.4, indicating an age of around 390 million years after the Big Bang. This validation of an early galaxy adds to our understanding of the early Universe’s evolution and sets the stage for further exploration with the JWST.

The recently confirmed early galaxy, Maisie’s Galaxy, serves as evidence that the early Universe is more populated than anticipated. Its discovery the JWST underlines the importance of meticulous analysis when studying distant celestial objects. By measuring redshift, astronomers can infer the time at which light was emitted. The JWST, equipped with infrared technology, allows scientists to explore the early Universe in unprecedented detail.

Initially, the redshift estimate for Maisie’s Galaxy was based on its brightness, determined through photometry. This estimate placed the galaxy’s observation around 366 million years after the Big Bang. To refine this estimation, astronomers employed the JWST’s NIRSpec instrument. Through spectroscopy, the instrument analyzes the different wavelengths of near-infrared light, providing a more precise analysis. The revised redshift value for Maisie’s Galaxy is z=11.4, indicating an observation age of approximately 390 million years post-Big Bang. This suggests that the light from the galaxy traveled for around 13.4 billion years before reaching the JWST.

In addition to confirming Maisie’s Galaxy, the research also examined two other early Universe galaxies discovered as part of the Cosmic Evolution Early Release Science (CEERS) Survey, which led to the identification of Maisie’s Galaxy. One galaxy exhibited a redshift consistent with the photometric estimate, while the other had a significantly different redshift value after spectroscopic follow-up.

The misidentification highlights the challenges of interpreting high-redshift objects that possess overlapping characteristics, known as the “triple overlap zone.” Consequently, careful consideration is essential when studying galaxies with unusually high redshifts. The confirmation of Maisie’s Galaxy, as well as the lessons learned from the misidentified galaxy in the CEERS survey, contribute to a better understanding of the early Universe’s dynamics.

Source: The research has been published in Nature.