The Cosmic Dawn Center (DAWN) is located in Copenhagen at the Niels Bohr Institute, University of Copenhagen, and at the Space division of the Technical University of Denmark (DTU-Space). It is a international basic research center supported by the Danish National Research Foundation. 

The center is dedicated to uncovering how and when the first galaxies, stars and black holes formed, through observations with the prime telescopes of the next decade (ALMA, JWST, Euclid, E-ELT, HST) as well as through theory and simulations.

DAWN's research is focused on the specific period in the history of the Universe known as Cosmic Dawn. This previously unexplored period, 300-600 million years after the big bang is when the first stars, black holes and galaxies are believed to have formed.

The Cosmic Dawn Center is involved in a number of observational surveys, utilizing multiple instruments and telescopes. The abundant data emerging from these tools is analyzed through both theoretical models and numerical simulations.

We study the birth, life, and death of galaxies. Additionally, we study the smaller scales, namely the gas and dust that lies in between the galaxies' stars — the interstellar medium — and the larger scales, namely the effect that the galaxies have on their environment in the early Universe; the so-called Epoch of Reionization.

First Galaxies

Galaxies are the building blocks of the Universe, and understanding how, and how soon, these enigmatic structures of gas, stars, and dark matter arose, is an observationally challenging task, since it involves detecting the faintest sources, almost at the edge of the observable Universe.

The currently most distant — and hence earliest — galaxy is seen at an epoch where the Universe was only 400 million years old, 3% of its current age. The first stars were formed at half this age, but have not yet been observed directly.

DAWN is involved in the James Webb Space Telescope (JWST), which was launched in December 2021, providing unprecedented deep exposures of some of the very first galaxies and protogalaxies.

Galaxy evolution

Galaxies evolve through both internal and external processes: Gas is converted to stars which pollute the interstellar medium with heavy elements, some of which form dust grains. Spiral arms form, and gas is ejected as galactic winds, triggered by the feedback of stars and quasars. At the same time, galaxies accrete new gas from the intergalactic medium, and merge with other galaxies.

The interplay between these processes determines the fate of a galaxy — whether it will turn out a flat and star-forming spiral galaxy, an elliptical, red and "dead" galaxy, or something else.

The evolution takes place over timescales of hundreds of millions of years, and hence cannot be observed "live". But studying the statistical properties of large samples of galaxy populations through observational surveys and theoretical modeling, DAWN continuously contributes to expand our cosmological horizon.

Quenching

Some galaxies continue to form stars from the time they are formed and until today. The beautiful bluish spiral galaxies are an example of this. However, others — typically the most massive and elliptical galaxies — at some point cease to form stars. As the short-lived, blue stars die out and the long-lived, red ones remain, these galaxies get their characteristic orange-reddish color.

What is the cause of this so-called quenching? When did it happen, and why doesn't star formation stop in all galaxies? What is the role of galaxy merging versus the role of stellar feedback and active galactic nucleus activity? These are questions that DAWN seeks to answer, using telescopes such as the Atacama Large Millimeter Array and the Very Large Telescope.

The interstellar medium

Whether stars die with a whimper or with a bang, they return their gas to the space in between them, only now it is polluted with heavier elements, or metals.

These elements are important in several ways: Not only the metals themselves, but also the molecules and the dust that they form, affect observations both in emission and in absorption. Acting as a coolant, they facilitate star formation, and through the many electronic transitions of metals and molecules and the large cross sections of dust grains they engender massive outflows through stellar and galactic winds.

These processes are interesting in themselves, but also have major impacts on the evolution of galaxies. Analyzing the interstellar medium is thus pivotal to understand galaxies. Notably, DAWN searches for signatures of some of the first molecules to form, such as carbon monoxide.

Reionization

In addition to all the action happening in the Universe in the form of planets forming, stars exploding, galaxies forming, etc., through its history the Universe has also experienced a number of global transitions. Most of these took place in the early Universe, in particular during the Big Bang.

When the Universe had cooled enough that neutral atoms could form, it remained neutral for several hundred millions of years. However, roughly half a billion years after the Big Bang, a global phase transition took place, where the entire vast space between the galaxies was re-ionized.

The sources of the ionizing radiation was probably hot stars in the first galaxies, but quasars also played a role. The transition was fast, cosmologically speaking, but exactly how did it progress? And how clumpy was the reionization? Before the epoch of reionization, light from galaxies has a hard time traveling through the Universe, but if reionization happened in a percolative manner, with large ionized bubbles around some galaxies, these may still be detected. DAWN investigates this interesting epoch in particular through numerical simulations.

Instruments:

James Webb Space Telescope:

If you are interested in writing a project (this could be a first year project, a bachelor project or a master's thesis) under supervision of a DAWN employee please feel free to contact a DAWN'er. 

All publications by DAWN here

DAWNs primary source of funding is a center of excellence grant from the Danish National research foundation, which runs for up to 10 years, starting in the fall 2017. In addition to this, DAWN will support its members to obtain personal grants from Danish and international funding agencies.

DAWN scientists at the moment hold three such grants, the ERC Consolidator Project: Connecting the Extreme (PI:Toft), the Villum Young Investigator Project: “Gas to dust, dust to stars” (PI: Magdis) and the DFF project: “The first generations of Galaxies” (PI: Watson).

The Danish National Research Foundation funds frontline, curiosity-driven research of the highest quality in Denmark. Read more >>

VILLUM FONDEN and VELUX FONDEN are philanthropic foundations and a part of THE VELUX FOUNDATIONS. Read more >>

The ERC's mission is to encourage the highest quality research in Europe through competitive funding and to support investigator-driven frontier research across all fields, on the basis of scientific excellence. Read more >>

The Visitor Programme is an integral part of DAWN. Visitors contribute to DAWN science in a number of ways; they infuse ideas and stimulate activity, add their expertise to on-going projects, get inspired and develop projects.

DAWN's visitor programme offers support for collaborators to come to DAWN for short and long stays. 

Opportunities for visits

There is a wide range of opportunities, both regarding scope and duration of the visit. The main criterion is to optimize scientific return. We support short-duration visits of days to weeks as well as long-term visits up to 12 months. Visits of more than 2-3 weeks are strongly encouraged.  Our associates have a standing invitation to visit.

Categories for visits

Generally, visits fall into one of these categories:

• Scientists of world-recognized caliber in one of the areas of interest to DAWN.
• Visitors who can contribute to DAWN science-related activities.
• Those who would like to collaborate on a specific scientific project.

Visits can take many forms. For example, a single scientist or a research team of co-authors may visit DAWN to contribute to a paper, an important application or a proposal.  Suggestions for mini-workshops are also welcome.

Prospective visitors are kindly requested to complete the Visitor Application Form. Before submitting the form, prior contact to a DAWN scientist is encouraged.

Support

Work space, computer access and administrative support are offered to all visitors. Request for financial support should be included on the Visitor Application Form. It is expected that most visits are at least co-funded.

Visitors are supported by the DAWN admin team, who will help with all of the administrative aspects of the visit, including housing.  Any specific or unusual computing needs must be communicated prior to arrival.

The prospective visitor's host will introduce the visitor to the scientific and non-scientific life at DAWN.

Helpful links for visitors

General information
Nearby accommodations
Copenhagen Airport
Public transportation
Visit Copenhagen.com
Visit Denmark.com
Copenhagen neighborhoods
Public transportation in Copenhagen

Local/Danish news in English
The Local
Copenhagen Post
Politiken

University of Copenhagen
Niels Bohr Institute 
Faculty of Science

Places of interest around Copenhagen
"DAWN Does Copenhagen"
Check out this Google map of different bars, restaurants, ice cream shops and attractions, so you'll always know what to do to enjoy your time in Copenhagen!

The restaurants are ordered by price level and if there is any event going on, the map will be updated to show relevant locations.

Historical sites in Copenhagen

For more information about DAWN, please contact the Coordinator or the Center Directors.

	Sune Toft, Center Director Niels Bohr Institute, University of Copenhagen Niels Bohr Building Jagtvej 128, 2. floor 01.2.I.078 2200 Copenhagen N. Phone: 61 68 09 30 Email: sune@nbi.ku.dk
	Thomas Greve, Co-Director Danmarks Tekniske Universitet Elektrovej, Bygning 327, rum 017 2800 Kgs. Lyngby Phone: 45 25 96 88 E-mail: tgreve@space.dtu.dk
	Peter Laursen, Communications Consultant Niels Bohr Institute, University of Copenhagen Niels Bohr Building Jagtvej 128, 2. floor 2200 Copenhagen N. Phone: 35 32 05 19 Email: pela@nbi.ku.dk
	Helena Baungaard-Sørensen, Section Secretary Niels Bohr Institute, University of Copenhagen Niels Bohr Building Jagtvej 128, 2. floor 01.2.I.036 2200 Copenhagen N. Phone: 22 53 11 78 Email: helena.baungaard@nbi.ku.dk