Natural superconductivity is extremely rare on our planet, but that might not be the same in the rest of the Universe. Researchers have now discovered naturally producing superconducting materials in alien objects for the first time, as they found superconductive grains inserted inside two separate meteorites that crash-landed on Earth.
The finding is the latest to demonstrate that meteorites are much more than space leftovers that fall into our atmosphere. Recent analyses have showcased possible extraterrestrial proteins, minerals that were never discovered before by us, and materials older than the Solar System.
Materials Not Found on Earth
Superconductivity is a series of physical properties that construct ‘perfect’ electrical conductivity in a material, which means that all electrical resistance inside the said material disappears, besides other impacts. This valuable phenomenon is incredibly rare in natural materials that have not been particularly treated.
In the space, things might be different, scientists say, as intense environments are creating exotic material phases not to found on Earth, through astronomical events that can unveil extremely high temperatures and incredibly high quantities of pressure.
The theory then says that due to this, meteorites could be great candidates for discovering naturally created superconducting materials developed in the odd conditions in space. The only issue is, earlier searches have never detected any such superconducting materials.
In new research led by scientists from UC San Diego, the experts analyzed pieces from 15 different meteorites, utilizing a method known as magnetic field microwave spectroscopy to identify traces of superconductivity inside the materials.
They got two clues; in an iron meteorite dubbed Mundrabilla, one of the most massive meteorites ever discovered, and the other in a rare ureilite meteorite known as GRA 95205.
Superconductive Properties in Meteorites
As per the team’s calculations, which also included vibrating sample magnetometry (VSM) and energy-dispersive X-ray spectroscopy (EDX) techniques, both of these meteorites were composed out of minute amounts of extraterrestrial superconductive grains.
“Naturally occurring superconductive materials are unusual, but they are particularly significant because these materials could be superconducting in extraterrestrial environments,” said physicist and nanoscientist James Wampler. “These measurements and analysis identified the likely phases as alloys of lead, indium, and tin.”
This is a significant discovery, but not only because it is a first in meteorites.
“Even the simplest superconducting mineral, lead, is only rarely found naturally in its native form, and, to our knowledge, there are no previous reports of natural lead samples superconducting,” the authors explain in their paper. “In fact, we are only aware of one previous report of superconductivity in natural materials, in the mineral covellite.”
Simply put, the fact that these superconductive grains were found in two different space rocks, means that more to these superconducting phase materials are present in space, and their properties could, therefore, have all types of impacts on their extraterrestrial settings.
“Superconducting particles within cold regions of space could have implications on the structure of stellar objects,” the team writes. “Specifically, superconducting particles could sustain microscopic current loops generated by transient fields and contribute to nearby magnetic fields.”
The research has been published in PNAS.