Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Baby booms and birth control in space

26.09.2007
Stars in galaxies are a bit similar to people: during the first phase of their existence they grow rapidly, after which a stellar birth control occurs in most galaxies.

Thanks to new observations from Dutch astronomer Mariska Kriek with the Gemini Telescope on Hawaii and the Very Large Telescope (VLT) in Chile, it is now known that a part of the heavy galaxies already stopped forming stars when the universe was still a toddler, about 3 billion years old. Astronomers suspect that black holes exert an influence on this halt in births.

Heavy galaxies are a boring phenomenon in the modern universe. They have an elliptical or a round form, the stars are evenly distributed over the galaxies and no more new stars are formed. The large quantities of stars, about 10 billion, and the current, low birth rate point to the fact that star formation must have been much higher in the past. When were these stars formed and why did the star formation subsequently stop?

Black holes as a birth control measure

The finite speed of light makes it possible to study the universe when it was much younger than now. With the help of spectrographs, such as the Gemini Near-InfraRed Spectrograph and SINFONI on the VLT, Mariska Kriek and her colleagues studied 36 heavy galaxies in the early universe. These galaxies are so far away that the light from them has taken 11 billion years to reach us. Interestingly the researchers found no signs of star formation for a large proportion of the galaxies observed. This new discovery contributes to the growing mass of evidence that the formation of new stars in heavy galaxies is strongly inhibited after an explosive baby boom.

This 'halt in births' is possibly due to the influence of the enormous black holes in the middle of the galaxies. The large amount of material attracted by these black holes generates enormous quantities of energy that subsequently heats up the gas in the galaxy. As a result of this heating the gas is no longer able to form new stars. The researchers did indeed discover a black hole in a number of the galaxies they investigated. These were mainly the galaxies where the star formation was inhibited less than 1 billion years ago. These results support the idea that black holes limit the birth of new stars.

Mariska Kriek | alfa
Further information:
http://www.strw.leidenuniv.nl
http://www.nwo.nl/nwohome.nsf/pages/NWOA_76TGL7_Eng

More articles from Physics and Astronomy:

nachricht Pulses of electrons manipulate nanomagnets and store information
21.07.2017 | American Institute of Physics

nachricht Vortex photons from electrons in circular motion
21.07.2017 | National Institutes of Natural Sciences

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: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

Im Focus: Laser-cooled ions contribute to better understanding of friction

Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision

Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

NASA looks to solar eclipse to help understand Earth's energy system

21.07.2017 | Earth Sciences

Stanford researchers develop a new type of soft, growing robot

21.07.2017 | Power and Electrical Engineering

Vortex photons from electrons in circular motion

21.07.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>