Astronomers using the James Webb Space Telescope (JWST) have made a groundbreaking discovery: a distant smudge of light known as "Maisie’s galaxy" is one of the earliest galaxies in the universe. Emitting light over 13 billion years ago, just 390 million years after the Big Bang, Maisie’s galaxy is now among the four oldest galaxies with confirmed ages through spectroscopy. This confirmation is a significant milestone for the JWST, marking the first spectroscopically confirmed distant galaxy in its observations.
The initial detection of Maisie’s galaxy occurred during the JWST’s debut season of observations in August 2022. The team determined its ancient age based on its brightness and redshift, which indicates the stretching of light into redder wavelengths as it travels through the expanding universe. However, to truly understand an object’s age, astronomers turn to spectroscopy. In this case, the JWST’s Near Infrared Spectrograph was used to analyze the light of both Maisie’s galaxy and another ancient object, CEERS-93316. While Maisie’s galaxy’s spectroscopic analysis confirmed its age, CEERS-93316 turned out to be a peculiar case, with its light misleadingly suggesting an older age. Overall, Maisie’s galaxy joins a select group of five galaxies, including the four previously confirmed by the JWST, that formed within the first 500 million years of the universe’s existence.
Astronomers Confirm Distant Galaxy as One of the Oldest in the Universe
Astronomers using the James Webb Space Telescope (JWST) have made an exciting discovery, confirming that a distant smudge of light known as "Maisie’s galaxy" is one of the earliest galaxies in the universe. The object, named after lead researcher Steven Finkelstein’s daughter, emitted light over 13 billion years ago, just 390 million years after the Big Bang. This impressive age places Maisie’s galaxy among the four oldest galaxies in the universe whose ages have been confirmed by spectroscopy.
The significance of Maisie’s galaxy lies in the fact that it was one of the first distant galaxies identified by the JWST, and it is the first of this set to be spectroscopically confirmed. Spectroscopy is a technique that splits light into its component frequencies, providing insights into the brightness, heat, and chemical composition of objects. This technique is crucial for accurately determining the age and distance of galaxies.
Initially detected in August 2022 during the JWST’s debut season of observations, Maisie’s galaxy was believed to be extremely old based on its brightness and redshift. Redshift measures the extent to which light stretches into redder wavelengths as it travels through the expanding universe. Higher redshift values indicate older and more distant light sources. However, relying solely on the brightness of light can be misleading, as different elements within stars and galaxies emit light at different frequencies. To overcome this, astronomers used spectroscopy to analyze the light of Maisie’s galaxy and another galaxy called CEERS-93316.
The spectroscopic analysis confirmed that Maisie’s galaxy is indeed as ancient as its brightness suggests. However, the same cannot be said for CEERS-93316. The researchers discovered that the galaxy’s light was distorted by globs of hot hydrogen and oxygen, causing it to appear bluer and older than it actually is. The revised estimate places CEERS-93316 at about 1 billion years after the Big Bang, removing it from the list of the oldest known galaxies.
Maisie’s galaxy now joins a short list of four other galaxies that were also discovered and spectroscopically confirmed by the JWST. These galaxies formed between 300 million and 500 million years after the beginning of space-time. This discovery is a significant contribution to our understanding of the early universe and adds to the growing body of knowledge being gathered by the JWST.
In conclusion, the confirmation of Maisie’s galaxy as one of the oldest galaxies in the universe is a remarkable achievement for astronomers using the JWST. By utilizing spectroscopy, they were able to accurately determine the age and distance of this distant object. This finding enhances our understanding of the early universe and contributes to the ongoing exploration of space and time.