1. How Webb Sees the Universe
The James Webb Space Telescope is specifically designed to observe infrared light.
Light from distant celestial objects shifts to longer wavelengths during its journey due to the expansion of the universe. Therefore, infrared observations provide a great advantage for studying very distant and ancient galaxies.
Webb’s high sensitivity allows astronomers to study the light from extremely distant galaxies whose details could not previously be seen. In this way, astronomers can look not only into the far reaches of space but also into the past of the universe.
2. Reaching the Universe’s First Galaxies
One of Webb’s most important research areas is the period known as the cosmic dawn, when the first stars and galaxies emerged.
This period covers the time interval from about 50 million to 1 billion years after the Big Bang.
Webb has begun to observe galaxies from this era in unprecedented detail. Some galaxies were found to be much brighter than expected, with small and dense star-forming regions.
3. A Galaxy 280 Million Years After the Big Bang
One of Webb’s most striking results regarding the early universe is the confirmation of a galaxy called MoM-z14.
The light from this galaxy was determined to have been emitted about 280 million years after the Big Bang.
The ability to observe a galaxy formed so early provides important data for models of how and how quickly galaxies form.
MoM-z14 is one of the examples showing that Webb is pushing the observable boundaries of the universe further toward the cosmic dawn.
4. The Unexpected Structure of the First Galaxies
Webb observations show that galaxies in the early universe are not simply smaller versions of today’s galaxies.
Some have quite compact structures and are forming stars intensely.
For example, Webb observed a galaxy that existed about 600 million years after the Big Bang, with a mass similar to what a young Milky Way might have had. Numerous star clusters in this galaxy were studied in detail.
5. Hydrogen Clouds in the Early Universe
In the early universe, the surroundings of galaxies were filled with large amounts of neutral hydrogen gas.
This gas made it difficult for certain types of light from young galaxies to travel through space.
However, Webb observed hydrogen light coming from some very distant galaxies.
This has raised new questions about how young galaxies affect the gas around them. Some observations suggest that the merging of galaxies could alter the surrounding gas, helping this light to escape.
6. The Role of Small Galaxies in the Universe’s Reionization
Webb’s spectroscopic observations revealed that very faint, small galaxies in the early universe could also produce significant amounts of energetic radiation.
These galaxies may be powerful sources of radiation capable of ionizing the neutral hydrogen gas around them.
Thus, strong evidence has been obtained that not only large and bright galaxies, but also small galaxies played an important role in the universe’s reionization process.
7. A New Perspective on the Formation of the First Black Holes
Webb is also studying black holes at the centers of galaxies in the early universe.
In an observation made in 2026, the mass of the black hole at the center of a very distant and small galaxy called Abell2744-QSO1 was measured to be about 50 million solar masses.
Observations produced results suggesting that this black hole may have formed before its host galaxy.
This finding adds a new dimension to the question of how supermassive black holes could grow so rapidly in the early universe.
8. GN-z11 and a Very Young Black Hole
The galaxy called GN-z11, studied by Webb, is also one of the remarkable examples of the early universe.
This galaxy existed when the universe was about 430 million years old.
Webb’s observations provided strong evidence for a supermassive black hole at the center of the galaxy, rapidly accreting matter.
Such observations help us understand how the first galaxies and the black holes at their centers evolved together.
9. Information Obtained from Webb’s Light Spectra
Webb does not only produce images of galaxies.
The telescope’s spectrometers can separate the light from celestial objects into different wavelengths, revealing the chemical traces within the light.
Since each element and molecule interacts with light differently, it leaves its own unique lines in the spectrum.
By studying these lines, information can be obtained about the chemical composition, temperature, motion, and density of a distant celestial object.
10. Studying Exoplanet Atmospheres
Webb’s research is not limited to the early universe.
The telescope also studies the atmospheres of planets orbiting other stars.
When an exoplanet passes in front of its star, some of the starlight passes through the planet’s atmosphere. Molecules in the atmosphere can absorb light at certain wavelengths.
By studying these small changes in the spectrum, Webb can obtain information about the substances in the atmosphere.
For example, distinct traces of water vapor were observed in the transmission spectrum taken from the atmosphere of WASP-96 b.
11. Webb’s Four Years of Scientific Observations
The James Webb Space Telescope began its scientific observations in 2022.
The data obtained in its early years has created a very broad field of research, from early galaxies to star-forming regions, from black holes to exoplanet atmospheres.
As of 2026, Webb’s observations are providing new data on previously unanswered questions such as the formation of galaxies and the growth of black holes in the early universe.
12. Re-evaluating Universe Models
Webb’s observations require some existing models of the early universe to be re-evaluated.
In particular, the discovery of bright galaxies at very early times, small galaxies with rapid star formation, and large black holes found in the very young universe highlight the question of how quickly these structures could form.
These results do not show that current cosmological models are completely wrong; however, they do indicate that more detailed models are needed to explain the formation speed of structures in the early universe.
13. Conclusion and Evaluation
Thanks to its infrared observation capability, the James Webb Space Telescope provides new information about the formation of galaxies, stars, and black holes by studying light from the very early periods of the universe.
The observation of galaxies that existed hundreds of millions of years after the Big Bang shows that the early universe has a more complex structure than expected. The role of small galaxies in reionization, the rapid growth of early black holes, and the identification of chemical substances in exoplanet atmospheres demonstrate that Webb can simultaneously investigate both the cosmic past and other planetary systems.
One of Webb’s most important results is that it can not only see celestial objects from the earliest periods of the universe at greater distances, but also obtain detailed information about how they formed by studying the chemical and physical traces in their light.