[ad_1]
The Hubble Ultra Deep Field offers a surprisingly deep look at a very small parcel of sky in the Fornax constellation, a 2004 270-hour sighting that revealed thousands of galaxies, some of which were seen shortly after their formation in the wake of the Big Bang.
Now astronomers using the MUSE spectrograph on the European Southern Observatory's very large telescope have discovered large atomic hydrogen clouds surrounding many of these galaxies. A discovery that indicates that almost the entire night sky shines with an invisible glow of hydrogen.
"Realizing that all the sky was shining in optics by observing the Lyman-alpha emission from distant hydrogen clouds was a surprise that literally opened the eyes," said Kasper Borello Schmidt, a member of the team of astronomers behind this result.
Themiya Nanayakkara, a member of the team, said: "The next time you observe the moonless sky and the stars, imagine the invisible glow of hydrogen: the first building block of the universe illuminating the whole sky night.
Lyman-alpha emissions are generated when the electrons contained in the atomic hydrogen atom fall back into the minimum permissible energy, thus producing ultraviolet radiation invisible to the human eye but lying within the limits of the MUSE spectrograph. ESO.
The European Southern Observatory has assembled a composite image showing the Lyman-alpha emissions superimposed on the Hubble Ultra Deep Field image.
Philipp Richter, another member of the team, said the MUSE observations provided "a completely new vision of the" cocoons "of diffuse gases that surround galaxies at the beginning of the Universe".
It is not yet clear which process is responsible for hydrogen emissions in the
[ad_2]
Source link
