The universe's magnetic fields have long been a subject of fascination and mystery. These invisible forces govern the movement of particles that form the building blocks of planets, stars, and galaxies. Despite their ubiquitous presence, the origins of magnetic fields in the universe remain unknown, and their evolution since the Big Bang is still a puzzle. A recent study, published in the Publications of the Astronomical Society of Australia, has unveiled the largest and most detailed map of cosmic magnetic fields ever created, thanks to the power of Australia's Murriyang radio telescope.
This groundbreaking achievement is a result of the Polarisation Sky Survey of the Universe's Magnetism (POSSUM) project, which has been a collaborative effort between astronomers and the ASKAP radio telescope in Western Australia. The telescope's 36 12-meter dishes provide an ultrawide view of the universe, enabling the detection of twisting light from magnetic fields beyond Earth. The previous largest map of magnetic fields, created in 2009, has been surpassed in size and detail by this new study.
The new map, named SPICE-RACS, is a collaboration between the POSSUM and Rapid ASKAP Continuum Surveys (RACS) teams. It covers nearly 4 million distant galaxies, with about 2 million being previously unseen. The map's colors represent the direction of magnetic fields, with red indicating fields pointing towards us and blue pointing away. The swirling and bubbly structure visible on the map is primarily from our own Milky Way galaxy, while the fine details reveal signatures from more distant parts of the universe.
This achievement is a significant step forward in our understanding of cosmic magnetic fields. It not only provides a more detailed view of the universe's magnetic landscape but also opens up new avenues for scientific inquiry. The data from this study is publicly available, allowing researchers worldwide to explore and analyze the map further.
Looking ahead, the POSSUM project is expected to conclude its observations by 2030, promising an even sharper magnetic map that will enable us to peer further back into the universe's history. This ongoing research is a testament to the power of human curiosity and our relentless pursuit of knowledge about the cosmos.
