From galactic magnetic fields, the cosmic baby boom and the turbulent formation of our Milky Way: In the March issue, bild der Wissenschaft reports on new insights into the development processes of the universe. Above all, the Gaia space telescope and the ALMA radio telescope observatory have led to exciting new insights that have changed the image of space and our cosmic home.
Many aspects of the cosmos will remain mysterious forever – but the curious gaze and the analytical mind of the human being can at least provide for a few aha moments. Every now and then, ideas have to be changed, supplemented or corrected. This scientific progress has accelerated increasingly in the last few years. Therefore, an update on the latest findings on the history of the development of the universe and its substructures is called for.
In the first article of the three-part title topic, the bdw astronomy expert Rüdiger Vaas focuses on new insights into the development of a special spiral galaxy: our Milky Way, on the outskirts of which the sun is located. Exactly because it is our cosmic home, the exploration of this galaxy is difficult, because it is not possible to have a clear view of the gigantic structure from the outside. In recent years, however, the astrometry satellite Gaia in particular has revolutionized the understanding of the structure and development of the Milky Way. Vaas reports, among other things, how new spiral arms were discovered and the gigantic structures that they contain. In addition, the turbulent history of our cosmic homeland is becoming more and more evident: It was therefore characterized by massive crashes and galactic cannibalism.
New aspects of the cosmic evolutionary history
In the second part of the title topic, the bdw author Thomas Bührke reports on new insights into gigantic magnetic fields that permeate the universe and have had a profound effect on the structure and star formation of the galaxies through their force. In the spiral galaxies, the large-scale magnetic field follows the spiral arms. Particle winds also transport the magnetic fields into the galactic outer areas. Although they can apparently slow down the formation of stars in galaxies, they are also the prerequisite for the formation of new stars at all, reports Bührke in the article “The magnetic power”.
Then the author goes further on the topic of star formation. It is becoming apparent that many stars formed in one fell swoop about ten billion years ago, he writes in the article “Cosmic Baby Boom”. The climax came about four billion years after the Big Bang. Since then the birth rate has been falling and a kind of cosmic twilight state has begun. The current number of stars can only be explained by the fact that matter is constantly flowing into the galaxies. In the meantime, more than 90 percent of the stars that have ever existed in the universe and will exist in the future, reports Bührke.
You can find out more in the March issue of bild der Wissenschaft, which will be available in stores from February 16.