Observation of one of the very first galaxies in the Universe

By combining data from two major European observatories located in Chile, and those from the Hubble Space Telescope, a team of scientists composed of an associate researcher and an astronomer of the Institut de recherche en astrophysique et planétologie (IRAP/OMP – CNRS/CNES/UT3 Paul Sabatier) discovered the farthest galaxy known to date. By studying the history of star formation in this galaxy, they were able to demonstrate that this galaxy already existed 250 million years after the Big Bang, thus bringing very strong constraints on the formation patterns of the first galaxies. The results of this study are published in the journal Nature on May 17, 2018.

This image acquired by the NASA/ESA Hubble Space Telescope shows the MACS J1149.5+2223 galaxy cluster. In the inset is the distant galaxy MACS1149-JD1, observed as it was 13.3 billion years ago by ALMA. The oxygen distribution detected by ALMA is red. Credit: ALMA (ESO/NAOJ/NRAO), NASA/ESA Hubble Space Telescope, W. Zheng (JHU), M. Postman (STScI), the CLASH Team, Hashimoto et al.

Understanding the formation and evolution of the first galaxies in the Universe is one of the great questions of modern astronomy. In particular, determining the time at which they began to form their first stars, and thus illuminate the Universe, is the cornerstone of models of the formation and evolution of the first galaxies. But locating these astronomical objects at the frontiers of the observable Universe is not easy, because these galaxies are much smaller than the Milky Way, and therefore much less luminous and most of them too faint to be detected by today’s telescopes.

However, the presence of a very massive cluster of galaxies on the line of sight, located between these first objects in the Universe and the telescopes, acts as a magnifying glass, amplifying the light emitted by the galaxies and making them detectable on Earth: this is the method known as gravitational telescopes.

Using this method, a team co-led by Takuya Hashimoto1 and Nicolas Laporte2 was able to locate the most distant galaxy known to date, by combining ultra-deep data from the Hubble Space Telescope and the ALMA and VLT observatories (in Chile). They were able to observe the galaxy MACJ1149-JD1 as it was 542 million years after the Big Bang. Thanks to their observations, they were able to determine the age of the stars in this galaxy and to show that they formed 300 million years earlier, when the Universe was 250 million years old! If MACSJ1149-JD1 is representative of this first generation of galaxies, it may well be that the galaxies formed at that time were much brighter than previously thought.

Zoom to galaxy MACS1149-JD1, the most distant galaxy discovered to date. The background image represents the galaxy cluster used to amplify the light of this first galaxy. The first zoom shows the configuration of the observations with the VLT, the last zoom (bottom right) shows the galaxy [in red] with the ALMA observations (in white outline).

Future studies to be conducted with the new JWST and ELT telescopes will confirm this hypothesis, not only by re-studying this galaxy with greater sensitivity, but also by increasing the samples of objects for which both the time of formation and the physical properties are known.

Notes

1Osaka Sangyo University / National Astronomical Observatory of Japan

2IRAP / University College London

Further Resources

  • Publication : Takuya Hashimoto, Nicolas Laporte, Ken Mawatari, Richard S. Ellis, Akio. K. Inoue, Erik Zackrisson, Guido Roberts-Borsani, Wei Zheng, Yoichi Tamura, Franz E. Bauer, Thomas Fletcher, Yuichi Harikane, Bunyo Hatsukade, Natsuki H. Hayatsu, Yuichi Matsuda, Hiroshi Matsuo, Takashi Okamoto, Masami Ouchi, Roser Pell´o, Claes-Erik Rydberg, Ikkoh Shimizu, Yoshiaki Taniguchi, Hideki Umehata, Naoki Yoshida.The onset of star formation 250 million years after the Big Bang,Nature
  • ESO Press Release : ALMA and VLT Find Evidence for Stars Forming Just 250 Million Years After Big Bang

IRAP Contacts

  • Roser Pello, astronome à l’Université Toulouse III – Paul Sabatier, Institut de Recherche en Astrophysique et Planétologie, Tél : 05 61 33 28 12, rpello@irap.omp.eu
  • Nicolas Laporte, chercheur associé à l’Institut de Recherche en Astrophysique et Planétologie, University College London,  n.laporte@ucl.ac.uk

More news

News

A new superstructure of galaxies in formation, discovered in a cold luminous zone of the distant universe

An international team of astrophysicists involving scientists* from the University of Paris-Saclay, CNRS, the University of Toulouse III – Paul Sabatier, Aix-Marseille University and the University Claude Bernard of Lyon […]

27.10.2021

News

COSI, the future gamma-ray space telescope selected by NASA

As part of its “Explorers” program, on October 18, 2021 NASA selected COSI (Compton Spectrometer & Imager) as the future space telescope, with a planned launch in 2025. COSI is […]

21.10.2021

News

A new success for the standard cosmological model

The joint analysis of the latest data from the Planck satellite and the properties of the very large catalogs of galaxies collected by the Sloan telescope support the model of […]

12.10.2021

Search