The early Universe hid ancient Galaxies: scientists discovered characteristic dust and metals

The early universe hid ancient galaxies

In the earliest Universe, massive Galaxies were actually much older than previously thought. It is the opinion of an international group of astronomers, which studies distant Galaxies using the most modern technologies, including the sublimated Atacama lattice. The researchers from the University of Copenhagen said that they were able to conduct a large multi-wavelength survey of distant galactic formations for the first time. It helped to understand how the initial phase of formation and evolution of galaxies in the Universe took place.

The astronomers did not expect to find mature galaxies, and the new data presents a more consistent picture of the average state in the early Universe. Science believes that most Galaxies formed during the early Universe.

For example, the Milky Way probably began its stages of birth about 13.8 billion years ago. And then the age of the Universe was only 10% of its current age. It is about 1.5 billion years after the Big Bang, when many Galaxies experienced a growth spurt. During that period, they were able to accumulate a significant amount of star mass and other properties that have been preserved in them to nowadays.

The Galaxies are considered mature if they contain significant amounts of dust and heavy elements such as metals. The dust is considered a byproduct of dying stars. But in the early Universe, Galaxies did not have time to form stars, let alone survive their death, so the scientists were surprised by the discovery of dust and metals.

An astronomer Seiji Fujimoto believes that sometimes the observed Galaxy is hidden by the dust, and it was possible to obtain any information about it only after the use of powerful optical telescopes that make it possible to see the state of the Galaxy through the veil that envelops it.

The modern ALMA installation was of great help in that, it can not only get an image of each Galaxy, but it is also able to see how the metal gas moves in individual Galaxies. The results of the new research, including the obtained unusual facts, will contribute to a fundamental understanding of the Universe.

Reference: “The ALPINE-ALMA [CII] survey – Survey strategy, observations, and sample properties of 118 star-forming galaxies at 4 < z < 6” by O. Le Fèvre, M. Béthermin, A. Faisst, G. C. Jones, P. Capak, P. Cassata, J. D. Silverman, D. Schaerer, L. Yan, R. Amorin, S. Bardelli, M. Boquien, A. Cimatti, M. Dessauges-Zavadsky, M. Giavalisco, N. P. Hathi, Y. Fudamoto, S. Fujimoto, M. Ginolfi, C. Gruppioni, S. Hemmati, E. Ibar, A. Koekemoer, Y. Khusanova, G. Lagache, B. C. Lemaux, F. Loiacono, R. Maiolino, C. Mancini, D. Narayanan, L. Morselli, Hugo Méndez-Hernàndez, P. A. Oesch, F. Pozzi, M. Romano, D. Riechers, N. Scoville, M. Talia, L. A. M. Tasca, R. Thomas, S. Toft, L. Vallini, D. Vergani, F. Walter, G. Zamorani and E. Zucca, 27 October 2020, Astronomy & Astrophysics. DOI: 10.1051/0004-6361/201936965