Imagine being able to turn off all the stars in our Milky Way. You would then “see” the rest of our Universe shining brightly. Rather than two to three thousand fires, astronomers say today. They indeed confirm that our Universe is brighter than the stars that we know of it would suggest.
Our Universe is bathed in the light emitted by the countless stars that form its galaxies. Countless, but which scientists have been able to get an idea of, all the same, for decades they have been observing them with increasingly efficient instruments. They were able to estimate, in particular, to what extent these stars shine and illuminate the space.
However, researchers have recently come to an astonishing conclusion. What connoisseurs call the Diffuse Background in the visible – the COB, for Cosmic optical backgroundlike background noise from sources outside our Milky Way — is at least twice as strong as astrophysicists previously thought.
Today, analysis of a much larger set of data — hundreds of images taken by the Long Range Reconnaissance Imager (Lorri) of NASA’s New Horizons mission — by < 50 AU New Horizons-LORRI Data" target="_blank">researchers from Rochester Institute of Technology (RIT, USA) confirms this. The light emitted by stars outside our galaxy is two to three times brighter than the light from known populations of galaxies.
Where does this light come from?
Should we conclude that there are still sources of light in our Universe that astronomers have not identified? A few days ago, physicists proposed to look for the error in the disintegration of particles of black matter in photons. However, what seems certain is what researcher Teresa Symons confides in a press release from the RIT : “Determining what produces this light could change our fundamental understanding of how the universe formed over time. »
But measuring the COB remains difficult to do. From Earth, the interplanetary dust prevent the collection of satisfactory data. Future missions or instruments may be able to contribute. Those called CIBER-2 and SPHEREx, for example. To be continued…