Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Galaxy 'Hunting' Made Easy

17.09.2007
Galaxies found under the Glare of Cosmic Flashlights

Astronomers using ESO's Very Large Telescope have discovered in a single pass about a dozen otherwise invisible galaxies halfway across the Universe. The discovery, based on a technique that exploits a first-class instrument, represents a major breakthrough in the field of galaxy 'hunting'.

The team of astronomers led by Nicolas Bouché have used quasars to find these galaxies. Quasars are very distant objects of extreme brilliance, which are used as cosmic beacons that reveal galaxies lying between the quasar and us. The galaxy's presence is revealed by a 'dip' in the spectrum of the quasar - caused by the absorption of light at a specific wavelength.

The team used huge catalogues of quasars, the so-called SDSS and 2QZ catalogues, to select quasars with dips. The next step was then to observe the patches of the sky around these quasars in search for the foreground galaxies from the time the Universe was about 6 billion years old, almost half of its current age.

"The difficulty in actually spotting and seeing these galaxies stems from the fact that the glare of the quasar is too strong compared to the dim light of the galaxy," says Bouché.

This is where observations taken with SINFONI on ESO's VLT made the difference. SINFONI is an infrared 'integral field spectrometer' that simultaneously delivers very sharp images and highly resolved colour information (spectra) of an object on the sky.

With this special technique, which untangles the light of the galaxy from the quasar light, the team detected 14 galaxies out of the 20 pre-selected quasar patches of sky, a hefty 70% success rate.

"This high detection rate alone is a very exciting result," says Bouché. "But, these are not just ordinary galaxies: they are most notable ones, actively forming a lot of new stars and qualifying as 'starburst galaxies'."

"We discovered that the galaxies located near the quasar sightlines are forming stars at a prodigious rate, equivalent to 20 suns per year," adds team member Celine Péroux.

These findings represent a big leap forward in the field, setting the stage for a very promising era of galaxy 'hunting'.

The astronomers now plan to use SINFONI to study in more detail each of these galaxies, by measuring their internal motions.

Henri Boffin | alfa
Further information:
http://www.eso.org/public/outreach/press-rel/pr-2007/pr-40-07.html

More articles from Physics and Astronomy:

nachricht Measured for the first time: Direction of light waves changed by quantum effect
24.05.2017 | Vienna University of Technology

nachricht Physicists discover mechanism behind granular capillary effect
24.05.2017 | University of Cologne

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: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Physicists discover mechanism behind granular capillary effect

24.05.2017 | Physics and Astronomy

Measured for the first time: Direction of light waves changed by quantum effect

24.05.2017 | Physics and Astronomy

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>