Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


The feeding habits of teenage galaxies

Astronomers have known for some time that the earliest galaxies were much smaller than the impressive spiral and elliptical galaxies that now fill the Universe.

Over the lifetime of the cosmos galaxies have put on a great deal of weight but their food, and eating habits, are still mysterious. A new survey of carefully selected galaxies has focussed on their teenage years — roughly the period from about 3 to 5 billion years after the Big Bang.

This deep view of a tiny patch of sky in the constellation of Cetus (the Sea Monster) shows a selection of galaxies, marked with red crosses, that were used in a new survey of the feeding habits of young galaxies as they grew through cosmic time. Each of the tiny blobs, galaxies seen as they were between three and five billion years after the Big Bang, has been studied in detail using ESO's VLT and the SINFONI instrument.
Credit: ESO/CFHT

By employing the state-of-the-art instruments on ESO's Very Large Telescope an international team is unravelling what really happened. In more than one hundred hours of observations the team has collected the biggest ever set of detailed observations of gas-rich galaxies at this early stage of their development [1].

"Two different ways of growing galaxies are competing: violent merging events when larger galaxies eat smaller ones, or a smoother and continuous flow of gas onto galaxies. Both can lead to lots of new stars being created," explains Thierry Contini (IRAP, Toulouse, France), who leads the work.

The new results point toward a big change in the cosmic evolution of galaxies, when the Universe was between 3 and 5 billion years old. Smooth gas flow (eso1040) seems to have been a big factor in the building of galaxies in the very young Universe, whereas mergers became more important later.

"To understand how galaxies grew and evolved we need to look at them in the greatest possible detail. The SINFONI instrument on ESO's VLT is one of the most powerful tools in the world to dissect young and distant galaxies. It plays the same role that a microscope does for a biologist," adds Thierry Contini.

Distant galaxies like the ones in the survey are just tiny faint blobs in the sky, but the high image quality from the VLT used with the SINFONI instrument [2] means that the astronomers can make maps of how different parts of the galaxies are moving and what they are made of. There were some surprises.

"For me, the biggest surprise was the discovery of many galaxies with no rotation of their gas. Such galaxies are not observed in the nearby Universe. None of the current theories predict these objects," says Benoit Epinat, another member of the team.

"We also didn't expect that so many of the young galaxies in the survey would have heavier elements concentrated in their outer parts — this is the exact opposite of what we see in galaxies today," adds Thierry Contini.

The team are only just starting to explore their rich set of observations. They plan to also observe the galaxies with future instruments on the VLT as well as using ALMA to study the cold gas in these galaxies. Looking further into the future the European Extremely Large Telescope will be ideally equipped to extend this type of study deeper into the early Universe.


[1] The name of the survey is MASSIV: Mass Assembly Survey with SINFONI in VVDS. The VVDS is the VIMOS-VLT Deep Survey. VIMOS is the VIsible imaging Multi-Object Spectrograph, a powerful camera and spectrograph on the VLT that was used to find the galaxies used in the MASSIV work, and measure their distances and other properties.

[2] SINFONI is the Spectrograph for INtegral Field Observations in the Near Infrared. It is the instrument on the VLT that was used for the MASSIV survey. SINFONI is a near-infrared (1.1-2.45 µm) integral field spectrograph using adaptive optics to improve the image quality.

More information

This research was presented in four papers describing the MASSIV survey that will appear in the journal Astronomy & Astrophysics.

The team is composed of T. Contini (Institut de Recherche en Astrophysique et Planetologie [IRAP], CNRS & Universite de Toulouse, France), B. Epinat (Laboratoire d'Astrophysique de Marseille, CNRS & Universite d'Aix-Marseille, France [LAM]), D. Vergani (Istituto di Astrofisica Spaziale e Fisica Cosmica-INAF, Bologna, Italy [IASF BO-INAF]), J. Queyrel (IRAP), L. Tasca (LAM), B. Garilli (Istituto di Astrofisica Spaziale e Fisica Cosmica-INAF, Milan, Italy [IASF MI-INAF]), O. Le Fevre (LAM), M. Kissler-Patig (ESO), P. Amram (LAM), J. Moultaka (IRAP), L. Paioro (IASF MI-INAF), L. Tresse (LAM), C. Lopez-Sanjuan (LAM), E. Perez-Montero (Instituto de Astrofisica de Andalucia, Granada, Spain), C. Divoy (IRAP) and V. Perret (LAM).

The year 2012 marks the 50th anniversary of the founding of the European Southern Observatory (ESO). ESO is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 15 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world's most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world's largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning a 40-metre-class European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become "the world's biggest eye on the sky".


- Research papers in A&A: Paper I, Paper II, Paper III, Paper IV

- MASSIV website:

- Photos of the VLT:

- Article about MASSIV in ESO Messenger:


Thierry Contini
Institut de Recherche en Astrophysique et Planétologie, CNRS & Université de Toulouse
Toulouse, France
Tel: +33 561 332 814
Cell: +33 662 641 268
Richard Hook
ESO, La Silla, Paranal, E-ELT and Survey Telescopes Public Information Officer
Garching bei München, Germany
Tel: +49 89 3200 6655
Cell: +49 151 1537 3591

Richard Hook | EurekAlert!
Further information:

More articles from Physics and Astronomy:

nachricht Graphene microphone outperforms traditional nickel and offers ultrasonic reach
27.11.2015 | Institute of Physics

nachricht Tracking down the 'missing' carbon from the Martian atmosphere
25.11.2015 | California Institute of Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Climate study finds evidence of global shift in the 1980s

Planet Earth experienced a global climate shift in the late 1980s on an unprecedented scale, fuelled by anthropogenic warming and a volcanic eruption, according to new research published this week.

Scientists say that a major step change, or ‘regime shift’, in the Earth’s biophysical systems, from the upper atmosphere to the depths of the ocean and from...

Im Focus: Innovative Photovoltaics – from the Lab to the Façade

Fraunhofer ISE Demonstrates New Cell and Module Technologies on its Outer Building Façade

The Fraunhofer Institute for Solar Energy Systems ISE has installed 70 photovoltaic modules on the outer façade of one of its lab buildings. The modules were...

Im Focus: Lactate for Brain Energy

Nerve cells cover their high energy demand with glucose and lactate. Scientists of the University of Zurich now provide new support for this. They show for the first time in the intact mouse brain evidence for an exchange of lactate between different brain cells. With this study they were able to confirm a 20-year old hypothesis.

In comparison to other organs, the human brain has the highest energy requirements. The supply of energy for nerve cells and the particular role of lactic acid...

Im Focus: Laser process simulation available as app for first time

In laser material processing, the simulation of processes has made great strides over the past few years. Today, the software can predict relatively well what will happen on the workpiece. Unfortunately, it is also highly complex and requires a lot of computing time. Thanks to clever simplification, experts from Fraunhofer ILT are now able to offer the first-ever simulation software that calculates processes in real time and also runs on tablet computers and smartphones. The fast software enables users to do without expensive experiments and to find optimum process parameters even more effectively.

Before now, the reliable simulation of laser processes was a job for experts. Armed with sophisticated software packages and after many hours on computer...

Im Focus: Quantum Simulation: A Better Understanding of Magnetism

Heidelberg physicists use ultracold atoms to imitate the behaviour of electrons in a solid

Researchers at Heidelberg University have devised a new way to study the phenomenon of magnetism. Using ultracold atoms at near absolute zero, they prepared a...

All Focus news of the innovation-report >>>



Event News

Fraunhofer’s Urban Futures Conference: 2 days in the city of the future

25.11.2015 | Event News

Gluten oder nicht Gluten? Überempfindlichkeit auf Weizen kann unterschiedliche Ursachen haben

17.11.2015 | Event News

Art Collection Deutsche Börse zeigt Ausstellung „Traces of Disorder“

21.10.2015 | Event News

Latest News

Siemens to supply 126 megawatts to onshore wind power plants in Scotland

27.11.2015 | Press release

Two decades of training students and experts in tracking infectious disease

27.11.2015 | Life Sciences

Coming to a monitor near you: A defect-free, molecule-thick film

27.11.2015 | Materials Sciences

More VideoLinks >>>