The Hubble Space Telescope managed to photograph the first phases of the explosion of a star (supernova), which occurred 11,000 million years agowhen the universe was still “primitive”.
A finding, underlines the Superior Council for Scientific Research (CSIC), that could improve scientific knowledge on the formation of stars and galaxies in the origins of the universe, and the image appears today published in Nature magazine.
The snapshot captured by Hubble – the space telescope of ESA and NASA – collects three different moments within hours of the stellar explosion and corresponds to a star that had a size 500 times larger than the Sun and exploded 11,000 million years ago.
This is the first time that a supernova in its early stages has been observed with such precision at this distance and that, moreover, it corresponds to a stellar explosion at the beginning of the universe’s history, CSIC points out in a press release released today.
“It is quite rare that a supernova can be detected at a very early stage, because that phase is very short,” according to Wenlei Chen, first author of the work and researcher at the University of Minnesota School of Physics and Astronomy (United States). . .
The Hubble telescope captured three unique moments of the supernova explosion in different phasesthat arrived on Earth at the same time.
The “gravitational lens”
This image was achieved thanks to the phenomenon called “gravitational lenses”: this effect is produced by a cluster of galaxies, with a mass thousands of times that of our Galaxy, which amplifies the light that is produced in very distant and aligned objects just behind the cluster, and works as a lens, increasing the light coming from the supernova, making it visible to the space telescope.
In this way, the galaxy cluster known as “Abel 370” it acted as if it were the lens, magnifying the light from the distant supernova, which was behind the cluster.
The images zoomed in by this lens took three different paths through the cluster, due to differences in length in the supernova’s light paths, slowing down time, and the curvature of space due to gravity. it had already been predicted by Albert Einsteinexplains the CSIC.
But because light takes different times to travel these three paths, the image captured by Hubble shows three moments of the explosion in a single snapshot, according to José María Diego, a researcher at the Institute of Physics of Cantabria (a Spanish mixed center of the CSIC and the University of Cantabria).
The researcher, who participated in the interpretation of the “gravitational lensing” effect and of the times between the different images of the supernova, specifies that between these three instants, one of them corresponds only to a few hours after the explosion.
In addition, the telescope captured the temperature variations of the supernova, which are observed with the variation of its color; when it is bluer, the supernova is hotter and, as it cools, its light becomes redder.
“You see different colors in all three images,” says Patrick Kelly, study leader and professor at the University of Minnesota School of Physics and Astronomy.
“In the core of the massive star there is a shock, it heats up and then you see it cools; it’s probably one of the most amazing things I’ve ever seen,” says the researcher.
The observations show that the red supergiant star was 500 times larger than the Sun, the CSIC says, and says this is the first time the research team has been able to measure the size of a dying star in the more primitive universe.
To achieve this, they relied on machine learning algorithms to measure the star’s brightness and cooling rate.
Now, taking advantage of the arrival of NASA’s new James Webb space telescope, the team plans to begin observing supernovae even further and to create a catalog of supernovae that will help understand whether stars that existed billions of years ago are different from those of the universe that is known today.