High-precision map of Milky Way’s magnetic fields charted

Washington -  In a new study, an international team of scientists pooled their radio observations into a database to produce the highest precision map to date of the magnetic field within our  own Milky Way galaxy.

Researchers at the Naval Research Laboratory, led by the Max Planck Institute for Astrophysics (MPA), used the database they created and were able to apply information theory techniques  to produce the map, Tracy Clarke, a member of the research team, said.

“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. The  resulting database is equivalent to peppering the entire sky with sources separated by an angular distance of two full moons,” she said.

The incredible volume of data results in a new, unique all-sky map that gives scientists the ability to measure the magnetic field structure of the Milky Way in unparalleled detail.

The map shows scientists a quantity known as Faraday depth, a concept that depends on magnetic fields along a specific line of sight. The research team created the map by combining the  more than 41,000 individual measurements using a unique image reconstruction technique.

The new high-precision map not only shows the Galactic magnetic field’s structure on large scales, it also reveals small-scale features that help scientists better understand turbulence in  the Galactic gas.

The map will give scientists valuable knowledge about the structure of Galactic magnetic fields throughout the Milky Way.