It’s a long-awaited snapshot: the James Webb Space Telescope photo, which captures thousands of galaxies, formed more than 13 billion years ago. It was unveiled on Monday evening during an event at the White House.
This photograph is “the deepest and clearest infrared image ever taken of the distant Universe so far,” NASA said.
The light, having traveled such a path, stretched from the visible spectrum to the infrared — a wavelength invisible to human eyes, but not to those of James Webb.
The latter aimed, for this shot illustrating the distant times of the cosmos, the cluster of galaxies SMACS 0723 which, acting as a magnifying glass, also made it possible to reveal very distant cosmic objects located behind it – an effect called gravitational lensing .
The image, which is teeming with detail, was taken over an observation time of 12.5 hours. It thus shows thousands of galaxies, at the heart of which certain structures “have never been seen before”, according to NASA. The research work is therefore just beginning. “Researchers will soon begin to learn more about the masses, ages, histories and compositions” of these galaxies, the space agency added.
A $10 billion engineering gem, one of James Webb’s main missions is to explore the early ages of the Universe. In astronomy, seeing far is equivalent to going back in time, the observed light having traveled for billions of years before reaching us.
“A new era has begun for astronomy,” Jonathan Lunine, an astronomer at Cornell University, told AFP, calling the image “fantastic”.
“While this is by no means the farthest Webb can see, (…) it shows the power of this remarkable telescope: enormous sensitivity, a wide range of wavelengths, and vivid image clarity. “, he added.
Continuation of the images on Tuesday
Although the names of James Webb’s first five cosmic targets were announced last week, the images had so far been jealously guarded in order to create suspense.
The following images of this genuine surprise bag will be revealed during a NASA online event on Tuesday morning. They must both impress the general public with their beauty, but also demonstrate to astronomers around the world all the power of the four scientific instruments on board.
Experts will be able to begin to interpret data collected using dedicated software, giving the starting signal for a great scientific adventure.
Two photos of nebulae – very photogenic and gigantic clouds of gas and dust where stars are formed – are on the program for Tuesday: the Carina Nebula, and that of the Austral Ring.
Another target, Stephan’s Quintet, a group of galaxies interacting with each other.
Other worlds
The first spectroscopy from the James Webb Telescope is also due to be made public on Tuesday. This is not an image per se, but a technique used to determine the chemical composition of a distant object. In this case, WASP-96 b, a giant planet composed mainly of gas and located outside our solar system.
Exoplanets (planets orbiting a star other than our Sun) are one of James Webb’s main areas of research. About 5,000 have been discovered since 1995, but they remain very mysterious.
The goal is to study their atmosphere to determine if some could turn out to be worlds conducive to the development of life.
Thanks to his observations in the near and mid-infrared, James Webb will be able to see through impenetrable dust clouds for his predecessor, the mythical Hubble Space Telescope. Launched in 1990 and still in operation, it has a small infrared capacity but operates mainly in visible light and ultraviolet.
Other major differences between the two telescopes: James Webb’s main mirror is almost three times larger than Hubble’s and it evolves much further: 1.5 million kilometers from Earth, against 600 km for Hubble.
The publication of these first images marks the official start of the very first cycle of scientific observation of the telescope.