The Hubble Space Telescope has discovered the farthest star ever observed: it’s called Erendel, and its light has traveled 12.9 billion years to reach us.
Rivaling the largest known stars, scientists estimate its mass to be at least 50 times the mass of our Sun, and millions of times brighter than it.
L’étoile détenant le précédent record avait elle aussi été observée par Hubble, en 2018. Mais cette dernière existait dans un Univers alors vieux de 4 milliards d’années, contre seulement environ 900 millions d pour’annéle lees apr researchers.
The discovery was published Wednesday in the prestigious scientific journal Nature.
“At first, we almost didn’t believe it,” lead author Brian Welch of Johns Hopkins University in Baltimore, USA, said in a statement.
It was he who was privileged to name this star: Earendel means “morning star” in Old English.
The researcher explained that the star “has been around for so long that it may not have been made of the same raw materials as the stars around us today.”
“Earendel’s study will provide a window into a period of the universe that we were unaware of, but that led to everything we know today,” he added.
This star will therefore be a prime target for the new James Webb Space Telescope, which is currently being calibrated in space. James Webb will be observing this new star this year, James Webb said in a press release for the European Space Agency (ESA), which operates the telescope with NASA.
Just as the sound of an object moving away becomes muffled, the wave of light stretches little by little and travels from the frequency visible to the naked eye, to the infrared frequency.
Unlike Hubble, which has only a small infrared power, James Webb will only work at these wavelengths, allowing us to go back even further.
Until now, only groups of stars could be seen at this distance, without being able to discern a star in particular.
But Earndell got a cosmic help: a phenomenon called gravitational lensing. A group of galaxies, located between us and the star, acts as a magnifying lens to amplify the light of the object.
The European Space Agency compares this effect to ripples on the surface of the water, which in good weather can create amplified beams of light on the pool floor.
This rare alignment should continue for years to come, according to astronomers.
