Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Witnessing the early growth of a giant

28.08.2014

First ever sighting of galaxy core formation

Astronomers have uncovered for the first time the earliest stages of a massive galaxy forming in the young Universe. The discovery was made possible through combining observations from the NASA/ESA Hubble Space Telescope, NASA's Spitzer Space Telescope, ESA's Herschel Space Observatory, and the W.M. Keck Observatory in Hawaii. The growing galaxy core is blazing with the light of millions of newborn stars that are forming at a ferocious rate. The paper appears in the journal Nature on 27 August.


A Cauldron of Star Birth in the Center of a Young Galaxy

Elliptical galaxies are large, gas-poor gatherings of older stars and are one of the main types of galaxy along with their spiral and lenticular relatives. Galaxy formation theories suggest that giant elliptical galaxies form from the inside out, with a large core marking the very first stages of formation.

However, evidence of this early construction phase has eluded astronomers — until now.

... more about:
»ESA »Hubble »NASA »Observatory »Physics »Space »Telescope »Universe

Astronomers have now spotted a compact galactic core known as GOODS-N-774, and nicknamed Sparky [1]. It is seen as it appeared eleven billion years ago, just three billion years after the Big Bang.

"This core formation process is a phenomenon unique to the early Universe," explains Erica Nelson of Yale University, USA, lead author of the science paper announcing the results, "we do not see galaxies forming in this way any more. There's something about the Universe at that time that could form galaxies in this way that it now can't. We suspect that the Universe could produce denser objects because the Universe as a whole was denser shortly after the Big Bang. It is much less dense now, so it can't do it anymore."

Although only a fraction of the size of the Milky Way, the infant galaxy is crammed with so many young stars that it already contains twice as much mass as our entire galaxy. It is thought that the fledgling galaxy will continue to grow, eventually becoming a giant elliptical galaxy. The astronomers think that this barely visible galaxy may be representative of a much larger population of similar objects that are too faint or obscured by dust to be spotted — just like the Sun can appear red and faint behind the smoke of a forest fire.

Alongside determining the galaxy's size from the Hubble images, the team dug into archival far-infrared images from NASA's Spitzer Space Telescope and the ESA Herschel Space Observatory to see how fast the compact galaxy is churning out stars. GOODS-N-774 is producing 300 stars per year. "By comparison, the Milky Way produces thirty times fewer than this — roughly ten stars per year," [2] says Marijn Franx of Leiden University in the Netherlands, a co-author of the study. "This star-forming rate is really intense!"

This tiny powerhouse contains about twice as many stars as our galaxy, all crammed into a region only 6000 light-years across. The Milky Way is about 100 000 light-years across.

Astronomers believe that this frenzied star formation occurs because the galactic centre is forming deep inside a gravitational well of dark matter, an invisible form of matter that makes up the scaffolding upon which galaxies formed in the early Universe. A torrent of gas is flowing into the well and into the compact galaxy, sparking waves of star birth.

"They're very extreme environments," said Nelson. "It's like a medieval cauldron forging stars. There's a lot of turbulence, and it's bubbling. If you were in there, the night sky would be bright with young stars, and there would be a lot of dust, gas, and remnants of exploding stars. To actually see this happening is fascinating."

The sheer amount of gas and dust within an extreme star-forming region like this may explain why they have eluded astronomers until now. Bursts of star formation create dust, which builds up within the forming core and can block some starlight [3] — GOODS-N-774 was only just visible, even using the resolution and infrared capabilities of Hubble's Wide Field Camera 3.

"This galaxy seems to have been furiously forming stars for more than a billion years," adds Franx. "We have spotted it very early on in its life. Shortly after the time period we're looking at, we think that this core will have stopped forming stars, and that smaller galaxies will have merged with it over the next 10 billion years until it expanded and grew outwards in size. It would resemble one of the mammoth, sedate ellipticals we see today."

"We had been searching for this galaxy for years, and it's very exciting that we finally found it", says Dokkum, "The big challenge is to understand the physics driving the formation of such objects. The James Webb Space Telescope, Hubble's successor, will be able to help us find an answer."

Notes

[1] The astronomers found the galaxy while poring over WFC3 images of thousands of galaxies catalogued in two large Hubble surveys of the distant Universe: 3D-HST and the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). They then used instruments at the W.M. Keck Observatory to measure the galaxy's distance from Earth, and to detect how fast the gas was moving, which confirmed its massive structure.

[2] Not all stars are the same mass as our Sun. The approximately 10 stars per year formed in the Milky Way will generally be less massive than our Sun.

[3] The dust build up in the compact galaxy obscures and reddens ultraviolet light from infant stars. The dust is absorbing and re-radiating that light as infrared light.

Notes for editors

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

The science paper announcing the results will appear in the journal Nature on 27 August 2014. The international team of astronomers in this study consists of E. Nelson (Yale University, USA), P. van Dokkum (Yale University, USA), M. Franx (Leiden University, The Netherlands), G. Brammer (STScI, USA), I. Momcheva (Yale University, USA), N. M. Forster Schreiber (Max Planck Institute for Extraterrestrial Physics, Garching, Germany), E. da Cunha (Max Planck Institute for Astronomy, Heidelberg, Germany), L. Tacconi (Max Planck Institute for Extraterrestrial Physics, Garching, Germany), R. Bezanson (University of Arizona, USA), A. Kirkpatrick (University of Massachusetts, USA), J. Leja (Yale University, USA), H-W. Rix (Max Planck Institute for Astronomy, Heidelberg, Germany), R. Skelton (SAAO, South Africa), A. van der Wel (Max Planck Institute for Astronomy, Heidelberg, Germany), K. Whitaker (Goddard Space Center, USA), and S. Wuyts (Max Planck Institute for Extraterrestrial Physics, Garching, Germany).

More information

Image credit: NASA, ESA, and E. Nelson (Yale University)

Contacts

Erica Nelson
Yale University
New Haven, Connecticut, USA
Tel: +1-203-432-0573
Email: erica.nelson@yale.edu

Marijn Franx
Leiden Observatory
Leiden University, The Netherlands
Tel: +31 71 527 5870
Email: franx@strw.leidenuniv.nl

Pieter van Dokkum
Yale University
New Haven, Connecticut, USA
Email: pieter.vandokkum@yale.edu

Georgia Bladon
ESA/Hubble, Public Information Officer
Garching bei München, Germany
Tel: +44 7816 291261
Email: gbladon@partner.eso.org

Georgia Bladon | ESA/Hubble Media Newsletter
Further information:
http://www.spacetelescope.org/news/heic1418/

Further reports about: ESA Hubble NASA Observatory Physics Space Telescope Universe

More articles from Physics and Astronomy:

nachricht International team of scientists unveils fundamental properties of spin Seebeck effect
29.07.2016 | Johannes Gutenberg-Universität Mainz

nachricht Astronomers discover dizzying spin of the Milky Way galaxy's 'halo'
26.07.2016 | NASA/Goddard Space Flight Center

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: Self-assembling nano inks form conductive and transparent grids during imprint

Transparent electronics devices are present in today’s thin film displays, solar cells, and touchscreens. The future will bring flexible versions of such devices. Their production requires printable materials that are transparent and remain highly conductive even when deformed. Researchers at INM – Leibniz Institute for New Materials have combined a new self-assembling nano ink with an imprint process to create flexible conductive grids with a resolution below one micrometer.

To print the grids, an ink of gold nanowires is applied to a substrate. A structured stamp is pressed on the substrate and forces the ink into a pattern. “The...

Im Focus: The Glowing Brain

A new Fraunhofer MEVIS method conveys medical interrelationships quickly and intuitively with innovative visualization technology

On the monitor, a brain spins slowly and can be examined from every angle. Suddenly, some sections start glowing, first on the side and then the entire back of...

Im Focus: Newly discovered material property may lead to high temp superconductivity

Researchers at the U.S. Department of Energy's (DOE) Ames Laboratory have discovered an unusual property of purple bronze that may point to new ways to achieve high temperature superconductivity.

While studying purple bronze, a molybdenum oxide, researchers discovered an unconventional charge density wave on its surface.

Im Focus: Mapping electromagnetic waveforms

Munich Physicists have developed a novel electron microscope that can visualize electromagnetic fields oscillating at frequencies of billions of cycles per second.

Temporally varying electromagnetic fields are the driving force behind the whole of electronics. Their polarities can change at mind-bogglingly fast rates, and...

Im Focus: Continental tug-of-war - until the rope snaps

Breakup of continents with two speed: Continents initially stretch very slowly along the future splitting zone, but then move apart very quickly before the onset of rupture. The final speed can be up to 20 times faster than in the first, slow extension phase.phases

Present-day continents were shaped hundreds of millions of years ago as the supercontinent Pangaea broke apart. Derived from Pangaea’s main fragments Gondwana...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

GROWING IN CITIES - Interdisciplinary Perspectives on Urban Gardening

15.07.2016 | Event News

SIGGRAPH2016 Computer Graphics Interactive Techniques, 24-28 July, Anaheim, California

15.07.2016 | Event News

Partner countries of FAIR accelerator meet in Darmstadt and approve developments

11.07.2016 | Event News

 
Latest News

Discovery of a novel gene for hereditary colon cancer

29.07.2016 | Health and Medicine

International team of scientists unveils fundamental properties of spin Seebeck effect

29.07.2016 | Physics and Astronomy

World first demo of labyrinth magnetic-domain-optical Q-switched laser

28.07.2016 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>