Scientists find water and compounds essential for life on ancient meteorites
SCIENTISTS have found water and or ganic compounds essential for life on two ancient meteorites that fell to Earth almost 20 years ago.
The research is based on the first ever comprehensive analysis of halite (salt-containing) crystals found within Zag and Monahans, two 4.5 billion-year-old rocks believed to have come from the asteroid belt between the orbits of Mars and Jupiter.
The study, published in Science Advances, appears to support data gathered in the recent years by Nasa’s Dawn spacecraft that suggests building blocks of life may be present on some of the neighbouring asteroids, particularly Ceres, the largest object in the asteroid belt.
An inter national team, including scientists from the Open University (OU) in the UK and Nasa Johnson Space Centre in Texas, found amino acids – which form the basis of proteins, hydrocarbons – organic compounds made up of hydrogen and carbon, and liquid water – the most important ingredient required to support life, within the salt crystals.
The meteorites fell to Earth in 1998 but the technology available at that time did not have the capability to detect traces of amino acids.
Using a combination high-sensitivity mass spectrometers, which detect different molecules based on their size, and NanoSIMS equipment, which uses beams of ions to study the chemical composition of organic materials, the scientists were able to determine the chemical composition.
Lead aut hor Dr Queenie Chan, a postdoctoral researcher at OU, said: “We collected the tiny salt crystals from the meteorites and dissolved them in water so that we could extract the amino acids and separate any organic compounds.
“We conducted our experiments in one of the cleanest laboratories in the world at the Nasa Johnson Space Centre, which avoided any contamination from things such as dust in the air.”
T he team used Raman spectroscopy, that uses light to detect the chemical composition of organic materials, to confirm the presence of water.
Dr Chan added: “Each salt crystal, about two millimetres and the c olour of a bl ue sapphire, is a package of organic compounds and the necessary building blocks of life.
“What’s even more incredible is that the salt crystals from both meteorites are believed to be from Ceres, which suggests that it could be a suitable place for the formation of life.”