Science News

Earth’s heavy metals created by supernova explosions according to new models

Using models made with supercomputers, a physicist from the University of Guelph came to the conclusion that most of the heavy elements on our planet were formed by explosions, naturally occurring in the distant past, of the so-called collapsar, a rare form of supernova caused by Wolf-Rayet stars with at least 30 solar masses that run on their axis very quickly.

These explosions caused by gravitational collapses would have released, according to the models of Daniel Siegel, all those heavy elements that we see today on our planet, from gold to platinum to end up with uranium and plutonium. This theory contrasts the more widespread theory that heavy elements originated from collisions between neutron stars or between a neutron star and a black hole.

Siegel’s models, however, show quantity and distribution of heavy elements “surprisingly similar” to those we can observe in the solar system. The collapsars can be considered fairly rare explosions, even rarer than the neutron star fusions themselves, but they expel a much higher quantity of material.

Now all that remains is to find a practical proof of this theory and for this reason, the researchers led by Siegel are waiting for the launch of the James Webb, the space telescope that will have to be launched in NASA in the coming years. In fact, this telescope will allow detecting particular radiations through which it will be possible to identify heavy elements expelled by the gravitational collapse of a star also in other galaxies.

The confirmation of the theory could also help to understand how our galaxy was formed and in general how the elements present on the periodic table were formed.

Science News

Calamari will take advantage of the acidification of the seas and will multiply out of all proportion

There is an animal that could take advantage of climate change, unlike most other species threatened by ongoing global warming. According to new research, which appeared in Conservation Physiology, squid not only will survive with the increasingly pressing acidification of the seas, caused by scientists according to the current global warming, but rather will exploit it to live better and multiply.

In fact, it is even more of a surprise because squid are notoriously very sensitive to changes in acidity so much so that they already live to their limits with regard to the surrounding oxygen. This is because they swim in a way that leads to a high exploitation of energy and this, in turn, to a greater need for oxygen that must flow into their blood. With a greater presence of carbon dioxide in the water, it was therefore thought that the squid would not have gone so well.

Scientists tested the effects of water acidification on two species of tropical squid, the two-colored pygmy squid (Idiosepius pygmaeus) and the Lesson squid (Sepioteuthis lessoniana). After subjecting them to higher levels of CO 2, those thought to be reached by the end of the century, the researchers realized that these two species were not influenced in motor performance, as reported by Blake Spady, researcher of the ARC Center of Excellence for Coral Reef Studies, one of the authors of the study, but in fact obtained advantages from the changed environmental conditions.

The reason? According to the researchers, tropical squid have developed particular ionic regulatory epithelia both in the gills and in the skin cells that are very effective in the face of environmental acid changes. Acidification of the waters therefore represents an advantage for them because with higher levels of carbon dioxide in the water the other animal species, and therefore also their prey, showed a net loss in their physical performance.

With this ability to adapt to environmental changes and the already high growth rates of squid, researchers predict their populations will increase significantly over the next few decades. Obviously such a situation will be substantially positive only for squid: alterations of the marine environmental balance of this type, which see clear increases in a few years or decades in the number of specimens of a single species or family, usually do not prove to be positive for all other animals in the food chain.