The study was conducted by an international team of astronomers

Feb 6, 2012 10:49 GMT  ·  By
The map of the Faraday effect caused by the magnetic fields of the Milky Way. Red and blue indicate regions of the sky where the magnetic field points toward and away from the observer, respectively
   The map of the Faraday effect caused by the magnetic fields of the Milky Way. Red and blue indicate regions of the sky where the magnetic field points toward and away from the observer, respectively

Radio observations from multiple international sources were recently pieced together by a group of astronomers, who managed to create an exquisite map of the magnetic fields within the Milky Way. Scientists with the Naval Research Laboratory (NRL) were also a part of the investigation.

The group was led by experts at the Max Planck Institute for Astrophysics (MPA), in Germany, who argue that the new map is the most detailed dataset on galactic magnetic fields ever produced. Creating the map was made possible through the use of information theory techniques.

What the map actually reveals is the Faraday depth, a quantity that is determined by magnetic fields along a specific line of sight. With the help of a unique image reconstruction technique, the group was able to group together 41,000 individual measurements of the Faraday depth.

In addition to revealing the large-scale structure of galactic magnetic fields, the map also displays some localized features. Astronomers now hope to be able to use these data to gain a deeper understanding of local turbulences they are seeing in galactic gas reserves.

“The key to applying these new techniques is that this project brings together over 30 researchers with 26 different projects and more than 41,000 measurements across the sky,” says NRL Remote Sensing Division expert Dr. Tracy Clarke.

“The resulting database is equivalent to peppering the entire sky with sources separated by an angular distance of two full moons,” the expert adds. His team contributed an important portion of the radio measurements that the MPA team stitched together.

This field of research is starting to be very exciting for specialists, especially because of the new radio telescopes that are currently being built at a variety of locations. Together, they will be able to analyze the sky like never before, in previously-obscured wavelengths.

In time, astronomers will be able to use the data they've collected on the Milky Way's magnetic fields to conduct investigations of other barred spiral galaxies across the Universe. Such investigations could reveal stellar formation patterns, as well as the main factors driving these phenomena.

“Despite this large catalog of date, there are still some large areas, especially in the southern sky, where only a few measurements have been recorded. So to gain a realistic map of the entire sky, researchers have to interpolate between the existing data points that they do have recorded,” a NRL press release says.