Scientists at Imperial College London have found out where some of the chemicals on Earth that are essential for life may have come from, using pieces of space rocks and studying them.
Scientists have discovered that around half of the Earth’s zinc comes from asteroids in outer space, past the planets Jupiter, Saturn, and Uranus. These same asteroids may have given us water too!
Volatiles are special kinds of elements or compounds that quickly turn into a gas when they’re heated up. They include the six most common elements found in living creatures, including water too! So, adding these materials to the environment was very important for life to start on Earth.
Scientists used to believe that the substances on Earth that could cause changes in states came from asteroids near our planet. However, new discoveries show us how important it is for Earth to have everything needed for life.
Professor Mark Rehkämper, from the Department of Earth Science and Engineering in London’s Imperial College said: “Our research showed that half of the zinc on Earth came from space beyond Jupiter’s orbit. This was a surprise to us, since current theories don’t predict this happening.”
Scientists used to think that Earth was mainly made up of materials from the inner parts of our Solar System. But new facts suggest that materials from the outer parts of our Solar System might have had a bigger part in creating Earth than we thought before.
Professor Rehkämper explained that material from the outer Solar System has an important job to do: it helps fill Earth with volatile chemicals that feed and protect life on the planet. Without this material, Earth would be drier, and life wouldn’t be able to exist. This was recently published in a journal called Science.
To do their research, the scientists took a look at 18 different meteorites. 11 of them had come from closer to the Sun and were called non-carbonaceous meteorites, while the other 7 were from further away and known as carbonaceous meteorites.
The scientists measured the amount of five different forms of zinc in each meteorite. Then, they compared these levels with Earth samples and found that the materials from carbonaceous meteorites supplied about half of all the zinc on Earth, though only 10 percent of its mass came from these meteorites.
The scientists did a study which showed that some materials with a lot of zinc and other unstable elements are very common in water, giving us clues about how Earth’s water was created.
Rayssa Martins, who wrote a research paper about this topic, said that for a long time people were aware of some substances being added to Earth. Her team’s findings showed that those substances were important for life because they created an environment with all the necessary elements which help organisms to survive and thrive.
Researchers are looking into rocks from Mars and the Moon to see what these rocks were like 4.1 to 3 billion years ago. There’s a theory that the Moon was created when a giant asteroid hit Earth about 4.5 billion years ago. What the researchers are doing is checking zinc isotopes (a kind of atoms) in moon rocks; this will tell them if this asteroid brought water and other stuff to Earth or not.
A group of scientists conducted a study and published it on the 26th of January, 2023, in a science journal. The article is called “Nucleosynthetic isotope anomalies of zinc in meteorites constrain the origin of Earth’s volatiles”. This study was funded by the Science and Technology Facilities Council (STFC). Rayssa Martins, who was part of this research team, was supported with funding from Imperial College London.
