When Celestial Bodies Became Cosmic Bombs: In the October issue, Bild der Wissenshaft presented new findings on collisions in the Solar System and how they shaped Earth. The giant impact hypothesis has focused on the so-called late heavy bombardment and two impact craters on German soil.
First a loose disk of matter circles around our young Sun, then the material collects to form larger and larger structures, until planets and moons emerge. Simply put, the large structures of our cosmic home system were built in this way. But the process also left a myriad of debris small and large: Planets and comets spin through the solar system and can repeatedly change their orbits when they collide with each other. So they can go on a collision course with planets and moons. Especially in the youth of our solar system, this resulted in many collisions. But there are still many potential impactors in space, as recent geological history shows traces of catastrophic impacts.
In the first article of a three-part title topic, BDW author Thorsten Dambeck focuses on two such geologically young craters in southern Germany: the Nördlinger Reiss and the smaller Steinheimer Basin. The two impact traces are not far away and were formed about 15 million years ago. Until now it is believed that a celestial body and its small moon crashed in this region at that time. But as Dumbeck reports in the article “Inferno in Germany’s Primeval Times”, there are also indications that there were two independent impact events that once devastated the region.
Explosion in Earth’s history
Dambeck then takes an in-depth look at Earth’s history and deals with a bombardment event of far greater dimensions: today it is believed that Earth collided with another planet shortly after its formation. According to the so-called giant impact hypothesis, our Moon originated from debris. The name of the collision partner has become Thea. In the article “Theia, desperately wanted”, the author reports on the results that the planet was much larger than previously thought. Isotope analyzes also suggest the origin of Theia. According to the article, perhaps parts of the mysterious celestial body are still sleeping deep inside the Earth.
Finally Dambeck deals with the extent and temporal course of cosmic bombardment throughout Earth’s early history. There are indications that about four billion years ago there was a phase with a particularly high number of impacts on the Moon and Earth. This era is known as the “Late Heavy Bombardment”. But as the author reports, doubts are growing about previous assumptions: Did the flood of cosmic impacts really occur when the first life on Earth was stirring up? This article also deals with possible reasons for the rising hail of bombs. According to the new findings, it is questionable whether changes in the orbits of Jupiter and Saturn triggered the impacts.
The cover theme “Cosmic Collisions” can be found in the October issue of Bild der Wissenshaft, which will be available in stores from September 21, 2021.