Have you ever wondered what the first stars in the universe looked like? How did they form and evolve? How did they influence the formation of galaxies and planets? These are some of the questions that astronomers and cosmologists are trying to answer by exploring the distant universe with powerful telescopes. And they have just made a remarkable discovery: the most distant star ever observed by NASA’s James Webb Space Telescope. This star, nicknamed Earendel, is located in a galaxy called the Sunrise Arc, which is magnified by a massive galaxy cluster that acts like a natural lens. In this article, we will tell you everything you need to know about this amazing discovery and what it can teach us about the early history of the universe.
What is gravitational lensing and how did it help JWST to detect Earendel?
Gravitational lensing is a phenomenon that occurs when a massive object, such as a galaxy or a galaxy cluster, bends the light from a distant source, such as a star or a galaxy, creating multiple images or arcs of the source. This effect can magnify and distort the source, making it easier to observe by telescopes. This is what happened with Earendel and the Sunrise Arc. The Sunrise Arc is a galaxy that lies behind a massive galaxy cluster called MACS J0717+3745, which acts like a natural lens for JWST. The cluster magnifies and stretches the galaxy into an arc shape, revealing Earendel as a bright spot in the arc.
Gravitational lensing is not only useful for detecting distant objects, but also for studying them in more detail. By measuring how much light is bent by the lensing object, astronomers can estimate its mass and distance. By comparing how different parts of the source are magnified and distorted by the lensing object, astronomers can infer its shape and structure. By analyzing how different wavelengths of light are affected by the lensing object, astronomers can determine its temperature and chemical composition.
Gravitational lensing is one of the main tools that JWST uses to explore the distant universe. JWST has a high sensitivity and resolution that allows it to detect faint and small objects that are magnified by gravitational lensing. JWST also has a wide wavelength coverage that enables it to observe different types of objects that are affected by gravitational lensing in different ways.
What kind of star is Earendel and how does it differ from other stars we know?
Earendel is a very special star. It is classified as a Population III star, which means it is one of the first stars ever formed in the universe, about 13 billion years ago. Population III stars are very different from other stars we know, such as our Sun or other Population I or II stars. Population III stars are much larger, hotter, brighter, and shorter-lived than other stars. They are also made of almost pure hydrogen and helium, with no traces of heavier elements like carbon or oxygen. These elements are produced by nuclear fusion inside stars and released into space when they die in supernova explosions. Population III stars are responsible for creating these elements and enriching the universe with them.
Earendel is the first Population III star ever observed by JWST, and only the second one ever observed by any telescope. The first one was detected in 2015 by the Hubble Space Telescope, and was named CR7, after the Portuguese soccer player Cristiano Ronaldo. Earendel is more distant and fainter than CR7, but also more magnified by gravitational lensing. Earendel is about 300 times more massive than the Sun, 100,000 times more luminous, and 10,000 degrees hotter. Earendel is also very young, only about 10 million years old, which is a fraction of the Sun’s age of 4.6 billion years. Earendel is expected to die soon in a spectacular supernova explosion, releasing its energy and elements into the surrounding space.
Earendel’s name comes from an Old English poem called “Christ I”, where it is used as a metaphor for the morning star or Venus. Earendel means “shining light” or “ray of light” in Old English, and is also related to the name of a mythical mariner in J.R.R. Tolkien’s works, who sailed across the sky with a silmaril on his brow. Earendel’s name was chosen by a team of astronomers led by Dr. Patrick Kelly from the University of Minnesota, who discovered the star using JWST’s data.
What can we learn from Earendel and how can it help us understand the early history of the universe?
Earendel is a very valuable source of information for astronomers and cosmologists. By studying its properties, such as its type, temperature, luminosity, and chemical composition, we can learn more about how stars formed and evolved in the early universe, and how they influenced the formation of galaxies and planets. We can also learn more about how gravitational lensing works and how it affects our observations of distant objects.
However, observing such distant objects is not easy. There are many challenges and limitations involved in this process. For example, Earendel is very faint and requires a very powerful telescope like JWST to detect it. Even with JWST’s advanced technology, Earendel’s image is still blurry and noisy due to atmospheric interference and cosmic background radiation. Moreover, Earendel’s light has been traveling for 13 billion years before reaching us, which means we are seeing it as it was in the past, not as it is now. Therefore, we cannot know what happened to Earendel after it emitted its light, or if it still exists today.
Despite these challenges and limitations, astronomers and cosmologists are eager to continue exploring the distant universe and finding more clues about its origin and evolution. JWST is not the only telescope that can do this. There are other telescopes, both on Earth and in space, that can complement JWST’s observations and provide more data and perspectives. For example, the Extremely Large Telescope, or ELT, is a ground-based telescope that is being built in Chile and is expected to be operational by 2025. ELT will have a 39-meter mirror, which will make it the largest optical telescope in the world. ELT will be able to observe Earendel and other distant objects with more detail and precision than JWST.
Conclusion
To conclude, we have talked to you about the discovery of the most distant star ever observed by NASA’s James Webb Space Telescope. This star, nicknamed Earendel, is located in a galaxy called the Sunrise Arc, which is magnified by a massive galaxy cluster that acts like a natural lens. This discovery is important because it allows us to see how stars formed and evolved in the first billion years of the universe, and how they influenced the formation of galaxies and planets. It also challenges us to overcome the difficulties and uncertainties of observing such distant objects and to use different telescopes and methods to gain more insight into the early history of the universe.
We hope you enjoyed this article and learned something new and interesting about astronomy and cosmology. Thank you for your attention and interest. If you have any questions or comments, please feel free to ask or share them below. 😊
