Ancient asteroid grains provide insight into the evolution of our solar system – Astrobiology

The UK’s National Synchrotron Facility, Diamond Light Source, has been used by a major international collaboration to study grains collected from a near-Earth asteroid to advance our understanding of the evolution of our solar system.

Researchers from the University of Leicester brought part of the Ryugu asteroid to Diamond’s Nanoprobe I14 beamline where a special technique called X-ray Absorption Near Edge Spectroscopy (XANES) was used to map the chemical states of the elements within the asteroid’s material, examining its composition in detail. The team also studied the asteroid grains using an electron microscope at Diamond’s Electron Physics Imaging Center (ePSIC).

Julia Parker is the lead beamline scientist for I14 at Diamond. She said: “The X-ray nanoprobe allows scientists to examine the chemical composition of their samples at micron to nano length scales, which is complemented by the nano to atomic resolution imaging in ePSIC. It is very exciting to be able to contribute to the understanding of these unique samples, and to work with the team in Leicester to show how Technologies in beamline, and proportionally in ePSIC, could benefit future sample return missions.”

The data collected at Diamond has contributed to a broader study of the signatures of space weathering on the asteroid. The original asteroid samples enabled the collaborators to explore how space weathering can alter the physical and chemical composition of the surface of carbonaceous asteroids like Ryugu.

The researchers discovered that Ryugu’s surface is drying out and that space weather is likely responsible. The results of the study, published today in the journal Nature Astronomy, led the authors to conclude that asteroids that appear dry on the surface may be water-rich, which may require a review of our understanding of the abundance of asteroid types and their formation history. asteroid belt.

Ryugu is a near-Earth asteroid, about 900 meters in diameter, first discovered in 1999 within the asteroid belt between Mars and Jupiter. It is named after the palace of the dragon gods under the sea in Japanese mythology. In 2014, Japan’s space agency JAXA launched the Hayabusa2 mission, an asteroid sample return mission, to rendezvous with asteroid Ryugu and collect samples of material from its surface and subsurface. The spacecraft returns to Earth in 2020, releasing a capsule containing valuable asteroid fragments. These tiny samples were distributed to laboratories around the world for scientific study, including the University of Leicester’s School of Physics and Astronomy, where John Bridges, one of the paper’s authors, is Professor of Planetary Sciences.

“This unique mission to collect samples of the solar system’s most primitive carbon building blocks needs the most detailed microscopy in the world, which is why JAXA and the fine-grained mineralogy team wanted us to analyze the samples in Diamond’s X-ray nanoprobe,” said John. Help us reveal the nature of space weathering on this asteroid with micrometeoroid impacts and the solar wind creating desiccated serpentine minerals, and the associated reduction of oxidized Fe3+ to more reduced Fe2+.

It is important to build experience in studying samples returned from asteroids, as in the case of the Hayabusa2 mission, because soon there will be new samples of other types of asteroids, the Moon and, in the next 10 years, Mars, that will be returned to Earth. The British community will be able to carry out some important analyzes because of our facilities at Diamond and electron microscopes at ePSIC.”

Ryugu’s building blocks are the leftovers of interactions between water, minerals, and organic matter in the early solar system before Earth formed. Understanding the formation of asteroids can help explain how the early solar system evolved, and thus how Earth formed. They may even help explain how life arose on Earth, as asteroids are thought to have provided much of the planet’s water as well as organic compounds such as amino acids, which provide the building blocks from which all human life is built. The information obtained from these small asteroid samples will help us better understand the origin of not only planets and stars but also the origin of life itself. Whether they are fragments of asteroids, ancient plates, or unknown viral structures, at the synchrotron, scientists can study their samples using a machine 10,000 times more powerful than a conventional microscope.

Based on research published in Nature Astronomy: ‘Space-dried skin hides Ryugu’s moist interior’ Dec 19, 2022 at 16:00 (London time), Dec 19, 2022 at 11:00 (US EST). DOI: 10.1038/s41550-022-01841-6

For more information: please contact Diamond Communications: Lorna Campbell +44 7836 625999 or Isabelle Boscaro-Clarke +44 1235 778130

Diamond Light Source: www.diamond.ac.uk Twitter: @DiamondLightSou

Diamond Light Source: Works like a giant microscope, harnessing the power of electrons to produce bright light that scientists can use to study anything from fossils to jet engines, viruses and vaccines. The machine accelerates electrons to speeds close to the speed of light so that they emit light 10 billion times brighter than the sun. These bright beams are then directed to the labs known as “beamlines”. Here, scientists use light to study a wide range of topics, from new medicines and treatments for diseases to innovative engineering and cutting-edge technology. Whether they’re fragments of ancient plates or unknown viral structures, at the synchrotron, scientists can study their samples using a machine 10,000 times more powerful than a conventional microscope.

Astrobiology