Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

An atlas of the Milky Way

31.08.2011
Sino-German research group draws a new map at the Urumqi radio telescope and discovers two supernova remnants

It may not be much use to hitchhikers through the galaxy, but it is extremely valuable to astronomers: the new radio atlas of the Milky Way. After almost ten years of work, researchers at the Max Planck Society and the Chinese Academy of Sciences have completed their investigation into the polarised radio emission in the galactic plane. The atlas is based on observations undertaken with the 25-metre radio telescope in the Chinese city of Urumqi and shows an area of 2,200 square degrees of the sky.

The radio survey covers the northern band of the Milky Way between ten and 230 degrees galactic longitude and between minus five and plus five degrees galactic latitude. The comprehensive survey shows the polarised radio emission of our galaxy at five gigahertz (corresponding to a wavelength of six centimetres) and thus at the highest frequency every recorded by terrestrial instruments.

The interstellar medium of the Milky Way comprises magnetic fields, electrons, atomic gas and other components which affect the polarisation plane of the radio emission. The Partner Group of the Max Planck Institute for Radio Astronomy, which was set up at the National Astronomical Observatory (NAO) in Beijing, investigated the properties of regions of large-scale diffuse emission and mapped the structure of large objects which cannot be observed by larger radio telescopes. These include densely ionised clouds – the HII regions – and the remnants of exploded stars.

The aim of the project was to map the large-scale magnetic field of the Milky Way. The German and Chinese researchers found a handful of peculiar clumps with very strong, regular magnetic fields (Faraday screens) and two new supernova remnants each measuring around one degree. These are the first sources of this type to be discovered with a Chinese radio telescope; astronomers are currently only aware of 270 such objects in the Milky Way. The researchers were also able to classify two incorrectly identified supernova remnants as thermal radio sources.

The new atlas needed more than 4,500 hours of observations to compile, and its angular resolution is similar to that of the 21-cm wavelength survey of the Milky Way obtained at the 100-metre radio telescope at Effelsberg. The comparative analysis of these two large-scale sky surveys at similar angular resolution leads to a better understanding of the processes occurring in the interstellar medium.

The establishment of the Partner Group in China dates back to a resolution of the Max Planck Society on November 9, 2000. The proposal involved collaboration in the exploration of magnetic fields in galaxies with special emphasis being placed on the investigation of the magnetic field of our Milky Way. The most important contribution made by the Max Planck Institute for Radio Astronomy in Bonn relates to the construction of a receiver for radio emission at six-centimetre wavelength including polarisation, which is being used at the 25-metre Nanshan radio telescope in Urumqi. The advantage of this radio telescope is its location at an altitude of 2,000 metres, where the better weather conditions are advantageous when observing radio emission at higher frequencies.

“Reciprocal visits to the institutes involved have formed a whole series of personal contacts,” says Richard Wielebinski, emeritus Director at the Max Planck Institute for Radio Astronomy. “As far as the German researchers are concerned, we have established a good collaboration with our Chinese colleagues. Things which began with the Partner Group will be continued on a personal level.”

“In the course of our work on this project, a total of five doctorates have been completed in our research group,” says Jin-Lin Han, the Head of the Partner Group in Beijing. “Our collaboration has significantly boosted the development of radio astronomy in China. The way the objective of the Partner Group has been achieved is excellent.”

The results of the research project encompass 24 scientific publications since 2002, most of them in the renowned European journal Astronomy & Astrophysics (A&A). The project has provided researchers with a great deal of experience in conducting radio continuum observations and means significant progress has been made in the construction of receiver systems for Chinese astronomy.

Dr. Norbert Junkes | EurekAlert!
Further information:
http://www.mpg.de/4406641/Milky_Way_atlas

More articles from Physics and Astronomy:

nachricht MSU astronomers discovered supermassive black hole in an ultracompact dwarf galaxy
14.08.2018 | Lomonosov Moscow State University

nachricht ASU astrophysicist helps discover that ultrahot planets have starlike atmospheres
13.08.2018 | Arizona State University

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: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

Im Focus: World record: Fastest 3-D tomographic images at BESSY II

The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.

Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

'Building up' stretchable electronics to be as multipurpose as your smartphone

14.08.2018 | Information Technology

During HIV infection, antibody can block B cells from fighting pathogens

14.08.2018 | Life Sciences

First study on physical properties of giant cancer cells may inform new treatments

14.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>