Through the use of a Hubble Space Telescope photograph, astronomers reported the finding of the furthest known star in March 2022. The old English name for “morning star” was Earendel, therefore they named it after that. The same star has now been examined by JWST’s Near-infrared Camera (NIRCam) and NIRSpec spectrometer, which have provided more information about it.
It looks that Earendel is a large B-type star. That places it evolutionarily on the Main Sequence, indicating that it is a hydrogen-burning star. It is a million times more bright and twice as hot as the Sun. Astronomers believe that this star, like numerous other similarly massive stars, may have a partner. They are almost 13 billion light-years away from us and lie so near to one another that it is difficult to distinguish them from one another. However, this star’s spectra, or the hues of its light, give some indication that a companion might be there. They should be able to identify the companion with the aid of additional research using the gravitational lens’s magnification and more in-depth images made with JWST’s NIRCam.
Only 900 million years after the Big Bang, the star Earendel began to radiate the light we see today. The gravitational lens that showed it is 4000 times more magnifying Earendel. Now, scientists are interested in learning if it belongs to the very first star-forming generations. If so, its spectra would show that it is primarily composed of hydrogen and helium. If it is a second-generation star, its light’s characteristics would also reveal more components. Rigel and Beta Centauri are two further instances of this kind of blue supergiant star.
Earendel’s Home in the Sunrise Arc
We see the host galaxy of this star as a lengthy streak of light in the form of a crescent. Gravitational lensing from the large galaxy cluster WHL0137-08 is to blame for the smearing. This far-off galaxy is depicted in great clarity in the NIRCam view. There are nurseries where the stars of tomorrow are being born. Some of those stars are just five million years old, making them relatively young.
Star clusters that are far advanced in their evolution can also be found in the galaxy. One of the clusters has a lifespan of roughly 10 million years. It may still be around in the present-day universe. The cluster provides scientists with some intriguing hints on the globular clusters that currently abound in our own Milky Way. It is possible that some of them developed at the same time as the distant clusters in WHL0137-08.
It’s interesting to note that the JWST image provides more information regarding the lensing effect on the far-off galaxy. The town of Earendel is situated along a lensing-created “ripple”. That is how it appears when it is not included in the distorted picture of its home galaxy. The infrared spectrometer (NIRSpec) on board JWST also collected data in addition to the NIRCam picture of this scene. It provides astronomers with further information regarding the precise separation between Earendel and its host galaxy.
Gravitational Lensing to See More Faraway Stars
Using its infrared-sensitive equipment, JWST has discovered additional far-off stars. Earendel continues to hold the distance record. But there are still a lot of other things to notice. Astronomers are working toward one of their ultimate goals: locating the very first stars to ever light.
Those very first things might have materialized as soon as 100 million years after the Big Bang. They were probably very large and incredibly bright. They heated and ionized the atmosphere surrounding them as they emerged from the Cosmic Dark Ages. In their hydrogen-burning cores, they created heavier chemical elements as they grew and died. When they perished, they dispersed those components throughout space, where they eventually seeded planets and future star generations.
We will learn a lot about all of those circumstances in the young Universe, the distribution of matter (including dark matter), and the eventual development of galaxies in the early epochs of cosmic time from the evidence of their lives and lifestyles.