Eos is the name of the Greek goddess of Aube. From now on, it is also that of a cloud of molecules 40 times larger than the moon, and 3,400 times more massive than the sun, revealed by a recent study published in Nature Astronomy.
But scientists could never have discovered it. Invisible to the naked and undetectable eye by conventional tools, he had escaped the eyes of scientists, reports CNN. “”This thing was almost in our cosmic garden, and we just missed it“Said Thomas Haworth, astrophysicist to the Queen Mary University of London and co-author of the study.
Our giant neighbor, invisible so far
In space, molecular clouds are areas composed of gas and dust from which hydrogen and carbon carbon carbon carbon molecules can form. These clouds are often very dense and cold, creating ideal conditions for the birth of new stars. Usually, scientists manage to spot them using radio and infrared observations capable of detecting the chemical signature of carbon monoxide.
The most beautiful photos captured by Thomas Pesquet from space
But then how was EOS being able to escape the radars of researchers? Especially since this cloud is closest to the earth: it is “only” 300 light years. “”It is surprising that there is something as big just in our solar neighborhood that we had not seen before“Said Melissa McClure, researcher at the University of Leiden in the Netherlands. It is because EOS contains very little carbon monoxide and therefore did not produce the signature detected by conventional tools.
The opportunity to better understand the history of our solar system
It was by falling on data collected in 2023 that Blakesley Burkhart, the main author of the study was able to detect EOS. These had been collected by an ultraviolet spectrograph mounted on a Korean satellite. Indeed, the role of the spectrograph is to decompose the ultraviolet light emitted by a material in its different wavelengths. A little in the same way as a prism breaks down the light. Thus, the hydrogen molecules present in EOS appeared as fluorescent, which made it possible to detect the extent of the cloud. By capturing the ultraviolet light emitted by hydrogen, scientists were able to observe EOS, literally brilliant in the dark.
As mentioned above, molecular clouds are places particularly conducive to the formation of stars. “”Our discovery of eos is exciting because we can now measure directly how molecular clouds are formed and dissociate, and how a galaxy begins to transform the gas and interstellar dust into stars and planetsS, “explained Blakesley Burkhart to CNN. Studying it will therefore be able to represent an unexpected opportunity to better understand the formation of our solar system.
