An early view of the universe as seen by the Hubble Space Telescope. Image credit: NASA, ESA, Hubble Frontier Field Group
Recently, the team of Brian Welch of Johns Hopkins University in the United States observed the farthest star from us through the Hubble Space Telescope. The star is 27 billion light-years away from Earth because it takes time for light to travel through the universe, which means that the star we see existed only 900 million years after the Big Bang. The findings were published in Nature on March 30.
The researchers discovered the star through a gravitational lensing process. The principle of the gravitational lensing process involves a relatively close galaxy or cluster twisting and amplifying light from a more distant object, i.e. the phenomenon of distant objects being magnified by a closer object. Like a lens through which we can see astronomical objects that would otherwise be too dark.
The galaxy where the new star is located is called the “sunrise arc” because its shape is formed by the gravitational lens stretching its rays. The researchers named the new star Erendel, a word derived from Old English — an Anglo-Saxon language — meaning “morning star” or “light of the rising sun.”
At present, researchers can’t determine how much the star is magnified by lensing, so it is not possible to determine the size of the star, but its mass is likely to be 50 to 100 times that of the Sun.
The accelerated expansion of the universe means that while the light emitted by Earendel will take about 12.8 billion years to reach Earth, it may now be about 27.7 billion light-years away from us. “Our world is going back to a very different era than it is today,” Welch said. Further observations of this star could allow researchers to determine exactly how stars in the early universe differed from recently formed stars.
Based on the actual size of Erendel, it could also help solve the puzzle of how supermassive black holes formed in the early universe. “If it’s really a very, very large star, then it could form an intermediate black hole that becomes the seed of a supermassive black hole.” Welch said.
The researchers hope to obtain further observational information through the James Webb Space Telescope to study Erendel’s true size and temperature. So far, they have been given the time to observe with the James Webb Space Telescope. (Source: China Science Daily Xin Yu)
Related paper information:https://doi.org/10.1038/s41586-022-04449-y