Astronomers use MUSE to see into the deep Universe like never before

The MUSE instrument on ESO’s Very Large Telescope has given astronomers the best ever three-dimensional view of the deep Universe. MUSE looked at the Hubble Deep Field South region for only 27 hours but the observations reveal the distances, motions and other properties of far more galaxies than ever before as well as faint objects that remained invisible to Hubble. Target at the RUG and other EU partners provide the data management system that enables scientific discoveries with MUSE.

Back in 1995, astronomers pointed the Hubble telescope at a region in the sky and kept collecting light for several days to produce the iconic Hubble Deep Field image. Together with its southern counterpart, Hubble Deep Field South taken two year later, it provided a unique look into the Universe, revealing many secrets about its early existence. Many more remained hidden. Twenty years later, technological advances have equipped astronomers with new instruments allowing them to observe the same spot in the sky from Earth for a much shorter period of time and see better and further than Hubble did. TheMUSE instrument (Multi-Unit Spectroscopic Explorer) was mounted on the ESO-operated Very Large Telescope located up in the mountains of Chile in 2014. Soon after commissioning, astronomers steered it to observe the Hubble Deep Field South region. The quality of the observational data exceeded their expectations revealing not only detailed information about the motion, distance and composition of 189 galaxies, but more than 20 extremely faint galaxies that could not be detected with Hubble. “After just a few hours of observations at the telescope, we had a quick look at the data and found many galaxies — it was very encouraging. And when we got back to Europe we started exploring the data in more detail. It was like fishing in deep water and each new catch generated a lot of excitement and discussion of the species we were finding,”  explained Roland Bacon (Centre de Recherche Astrophysique de Lyon, France, CNRS) principal investigator of the MUSE instrument and leader of the commissioning team.

Target, at the University of Groningen, has developed a system together with the MUSE partners that allows Bacon and his team to explore MUSE data. Based on Target's WISE technology and dubbed MUSE-WISE, the system maintains a distributed storage environment for MUSE data consisting of several data centers across Europe. It also provides a package of services to astronomers to access and process MUSE data. "MUSE produces a wealth of complex data and organizing, managing and reducing these data sets is a challenging task for a collaboration spanning four countries and multiple institutions. The WISE technology provided by Target, as implemented in the MUSE-WISE system offers this infrastructure and allows scientists to spend most of their time on the analysis and scientific interpretation of the data.” said Jarle Brinchmann an assistant professor of astronomy at the Leiden Observatory and head of MUSE’s data management group. Target is a large collaborative project focused on providing ICT infrastructure and expertise to scientists across multiple disciplines who conduct data-intensive research. The Target expertise center located at the Center for Information Technology maintains petabyte storage and HPC facilities used for data-handling of data from astronomical projects like MUSE, LOFAR, Euclid as well as large medical studies like LifeLines and GLIMPS. "This is a example of how novel instrumentation and innovative IT infrastructure can lead to thrilling scientific discovery" noted the Target coordinator Prof. Edwin Valentijn from the Kapteyn Astronomical Institute.

The power of the MUSE instrument lies in its ability to produce high-resolution image and spectroscopic data simultaneously. Before MUSE, astronomers who identified interesting objects (stars or galaxies) in their images had to observe these objects separately with dedicated spectrographs in order to learn more about their distance and composition. By looking carefully at all the spectra in the MUSE observations of the HDF-S, the team measured the distances to 189 galaxies. They ranged from some that were relatively close, right out to some that were seen when the Universe was less than one billion years old. This is more than ten times the number of measurements of distance than had existed before for this area of sky. For galaxies at smaller cosmic distances, MUSE is powerful enough to resolve their internal structure and motion properties allowing astronomers a better look at their evolution through cosmic time. “Now that we have demonstrated MUSE’s unique capabilities for exploring the deep Universe, we are going to look at other deep fields, such as the Hubble Ultra Deep field. We will be able to study thousands of galaxies and to discover new extremely faint and distant galaxies. These small infant galaxies, seen as they were more than 10 billion years in the past, gradually grew up to become galaxies like the Milky Way that we see today,” said Roland Bacon. Here at the University of Groningen, the Target team will continue to provide astronomers and other scientists with the best ICT tools and infrastructure to enable new and equally exciting discoveries.

MORE INFORMATION

Offical press release by ESO

ESOcast 72 - Looking Deeply Into the Universe in 3D

“The MUSE 3D view of the Hubble Deep Field South” by R. Bacon et al., Astronomy & Astrophysicson, 26 February 2015.

NOVA press news (in Dutch)

CONTACT

Gijs Verdoes Kleijn
Kapteyn Astronomical Institute
University of Groningen
Tel: +31 50 363 4086
Email: verdoes astro.rug.nl

Edwin Valentijn
Kapteyn Astronomical Institute
University of Groningen
Tel: +31 50 363 4011
Email: valentyn astro.rug.nl