Scientists have attempted to solve the mystery of why sulfur is observed in space in much smaller quantities than expected. They suggested that the reason for this is that it is present in molecular clouds in several different forms, which are constantly transforming into one another.
Mystery of sulfur in space
An international group of researchers recently published a study in Nature magazine in which they attempted to solve a fairly old astronomical mystery. It concerns the fact that in the Universe, and in particular in molecular clouds from which stars are formed, there is significantly less sulfur than there should be.
There is enough sulfur on Earth and other planets in the Solar System. Acid rain, gypsum deposits, and volcanoes on Io are evidence of this. Overall, it is estimated that it should be the tenth most abundant element in the Universe.
So, why is it that in molecular clouds, where everything should start, it’s three orders of magnitude less than it should be? Scientists believe that in this case, “not observed” does not mean “no.” It is quite possible that we simply cannot see the sulfur.
Forms of sulfur
It all comes down to how scientists determine the presence of a particular substance in astronomical objects. This is done using spectrometry. It consists in the fact that molecules of a specific shape leave traces that are visible in light dispersed into a “rainbow.”
In other words, our ability to see sulfur depends on our knowledge of its form. And in a new study, scientists have suggested that it may exist in two forms: octasulfur crowns, which are groups of eight sulfur atoms configured in ring-shaped crowns, and polysulfanes, chains of sulfur atoms linked by hydrogen.
These molecules can form on icy dust grains, fixing sulfur in rigid forms. It’s not so easy to identify them there. What’s more, one form constantly transforms into another. And in such conditions, even with the help of such a powerful instrument as the James Webb Space Telescope’s spectrograph, it is not so easy to detect it.
According to phys.org
