meteorites – Lightsources.org

Scientists confirm the presence of rare diamond in stony meteorites

2022/09/142022/09/20

Australian and international researchers have used ANSTO’s Australian Synchrotron to confirm the presence of an unusual diamond found in stony meteorites.

The ureilite meteorites contain a rare hexagonal form of diamond, lonsdaleite, that may have been formed shortly after an ancient dwarf planet collided with a large asteroid about 4.5 billion years ago.

The team of scientists from Monash University, RMIT University, CSIRO, the Australian Synchrotron and Plymouth University confirmed the existence of lonsdaleite and clarified how it was formed in a paper in the Proceedings of the National Academy of Sciences (PNAS) journal. The study was led by geologist Professor Andy Tomkins from Monash University.

Beamline scientists Dr Andrew Langendam and Dr Helen Brand assisted the team with experiments on the powder diffraction beamline.

“Information that indicated the presence of lonsdaleite was gained by other methods but what was needed most was confirmation of lonsdaleite,” explained Dr Langendam.

“Our powder diffraction beamline is able to differentiate complex mineral phases, such as those found in the meteorites.

“X-ray diffraction revealed a series of peaks representing pyroxene, goethite, olivine and lonsdaleite,” he added.

Read more on the ANSTO website

Image: Mineral map highlighting the partial replacement of lonsdaleite by diamond

Credit: Authors Sequential Lonsdaleite to Diamond Formation in Ureilite Meteorites via In Situ Chemical Fluid/Vapor Deposition PNAS 119 (38) e2208814119

Exploring the scale of meteorite impact from minerals

2020/09/082020/09/08

Laboratory-based shock experiments on minerals

Key Points
– Shock experiments were performed on baddeleyite (a zirconia mineral) in a laboratory, during which time its crystal structure dynamics were observed directly using a synchrotron X-ray.
– The crystal structure changed upon compression before returning to its original state when released.
– Geologists can use this information to estimate the scale of a past impact event using baddeleyite present in rocks.

Collisions of celestial bodies have formed and affected the evolution of planets. One well-known hypothesis is that an asteroid impact caused the mass extinction of dinosaurs on Earth ~65 million years ago. Understanding the scale of an impact event is essential to studying the evolution of a similar planet. Impact events cause shock metamorphism in rocks and minerals in the crust of a planet (see Fig. 1), and shock metamorphosed minerals can be used to identify and date impact events and as barometric indicators. Baddeleyite (ZrO2) is one mineral that can be used as a shock-pressure barometer. The mineral is widespread on Earth, the Moon, Mars, and meteorites; it is also known to show traits of shock
metamorphism.

Read more on the KEK (Photon Factory) website

Image: Meteorite impact produces shock compressions in rocks. Source: KEK (Photon Factory)

A little bit of the moon just landed at ANSTO

2019/08/122019/08/12

Research on lunar meteorite and moon crater analogues coincides with Science Week.

Researchers at the Australian Synchrotron are currently collaborating on a particularly rare, other-worldly sample; a lunar meteorite. “Although we do work on the moons of the outer planets, I believe this is our first sample from Earth’s moon, which could be more than four billion years old,” said Dr Helen Brand, planetary geologist and senior beamline scientist at the Australian Synchrotron.

Lunar meteorites are rocks found on Earth that were ejected from the Moon by the impact of an asteroid or another body. “These objects, which originate primarily from the moon’s crust, are extremely rare and precious. Because of their scarcity, scientists often use analogues or man-made versions of meteorites for investigations. “At the moment it is quite exciting as I have two projects relating to actual and analogue lunar objects, both of which are scheduled for the Imaging and Medical Beamline at the Synchrotron,” she said. n, which could be more than four billion years old,” said Dr Helen Brand, planetary geologist and senior beamline scientist at the Australian Synchrotron.

Synchrotron techniques allow geologists to study the surface of Mars

2019/05/032019/05/06

State-of-the-art imaging uncovers the exciting life history of an unusual Mars meteorite

With human and sample-return missions to Mars still on the drawing board, geologists wishing to study the red planet rely on robotic helpers to collect and analyse samples. Earlier this year we said goodbye to NASA’s Opportunity rover, but Insight landed in November 2018, and several space agencies have Mars rover missions on their books for the next few years. But while we’re working on ways to bring samples back from Mars, geologists can study Martian meteorites that have been delivered to us by the forces at play in the Solar System. Earth is bombarded by tonnes of extraterrestrial material every day. Most of it comes from Jupiter Family Comets and the asteroid belt, and much of it burns up in the atmosphere or lands in the oceans, but meteorites from the Moon and Mars do make it to Earth’s surface. In research published in Geochimica et Cosmochimica Acta, scientists used a battery of synchrotron techniques to investigate a very unusual Martian meteorite, whose eventful life story offers some insights to the geological history of Mars.

Image: BSE image with locations for XANES/XRD and XRF map.

Meteorites suggest galvanic origins for martian organic carbon

2019/02/252019/02/26

The nature of carbon on Mars has been the subject of intense research since NASA’s Viking-era missions in the 1970s, due to the link between organic (carbon-containing) molecules and the detection of extraterrestrial life. Analyses of Martian meteorites marked the first confirmation that macromolecular carbon (MMC)—large chains of carbon and hydrogen—are a common occurrence in Mars rocks. More recently, researchers have applied the lessons taken from studies of meteorites to the data being gathered by the Curiosity rover, finding similar MMC signatures on Mars itself. Now, the central question is “what is the synthesis mechanism of this abiotic organic carbon?”

>Read more about on the Advanced Light Source website

Image: A high-resolution transmission electron micrograph (scale bar = 50 nm) of a grain from a Martian meteorite. Reminiscent of a long dinner fork, organic carbon layers were found between the intact “tines.” This texture was created when the volcanic minerals of the Martian rock interacted with a salty brine and became the anode and cathode of a naturally occurring battery in a corrosion reaction. This reaction would then have enough energy—under certain conditions—to synthesize organic carbon.
Credit: Andrew Steele

Simulating meteorite impacts in the lab

2019/02/052019/02/12

Scientists monitor the response of feldspar minerals to rapid compression

A US-German research team has simulated meteorite impacts in the lab and followed the resulting structural changes in two feldspar minerals with X-rays as they happened. The results of the experiments at DESY and at Argonne National Laboratory in the US show that structural changes can occur at very different pressures, depending on the compression rate. The findings, published in the 1 February issue of the scientific journal Earth and Planetary Science Letters (published online in advance), will aid other scientist to reconstruct the conditions leading to impact craters on Earth and other terrestrial planets.

Image: Scanning electron microscopy image of the micro-structure of albite prior to the rapid compression experiments.
Credit: Stony Brook University, Lars Ehm

From Moon Rocks to Space Dust

2018/06/112018/07/12

Specialized equipment, techniques, and expertise at Berkeley Lab attract samples from far, far away.

From moon rocks to meteorites, and from space dust to a dinosaur-destroying impact, the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) has a well-storied expertise in exploring samples of extraterrestrial origin.

This research – which has helped us to understand the makeup and origins of objects within and beyond our solar system – stems from the Lab’s long-standing core capabilities and credentials in structural and chemical analyses and measurement at the microscale and nanoscale.

Berkeley Lab’s participation in a new study, detailed June 11 in the journal Proceedings of the National Academy of Sciences, focused on the chemical composition of tiny glassy grains of interplanetary particles – likely deposited in Earth’s upper atmosphere by comets – that contain dust leftover from the formative period of our solar system.

That study involved experiments at the Lab’s Molecular Foundry, a nanoscale research facility, and the Advanced Light Source (ALS), which supplies different types of light, from infrared light to X-rays, for dozens of simultaneous experiments.

Image: Moon dust and rock samples photographed at Berkeley Lab.
Credit: Berkeley Lab

Possible Path to the Formation of Life’s Building Blocks in Space

2018/03/052018/03/08

Experiments at Berkeley Lab’s Advanced Light Source reveal how a hydrocarbon called pyrene could form near stars

Scientists have used lab experiments to retrace the chemical steps leading to the creation of complex hydrocarbons in space, showing pathways to forming 2-D carbon-based nanostructures in a mix of heated gases.

The latest study, which featured experiments at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), could help explain the presence of pyrene, which is a chemical compound known as a polycyclic aromatic hydrocarbon, and similar compounds in some meteorites.

A team of scientists, including researchers from Berkeley Lab and UC Berkeley, participated in the study, published March 5 in the Nature Astronomy journal. The study was led by scientists at the University of Hawaii at Manoa and also involved theoretical chemists at Florida International University.

Image: A researcher handles a fragment and a test tube sample of the Murchison meteorite, which has been shown to contain a a variety of hydrocarbons and amino acids, in this photo from a previous, unrelated study at Argonne National Laboratory. Experiments at Berkeley Lab are helping to retrace the chemical steps by which complex hydrocarbons like pyrene could form in the Murchison meteorite and other meteorites.
Credit: Argonne National Laboratory

From Antarctica to the beamline, #weekendusers

2018/02/122018/02/21

A Belgian team is trying to find out about the origin of the Solar System by studying micrometeorites from Antarctica on the Dutch-Belgian beamline (DUBBLE).

Sør Rondane Mountains, Antarctica, 2013. Steven Goderis, from the Analytical Environmental and Geochemistry (AMGC) research group in the Vrije Universiteit Brussel (Belgium), is part of a Japanese-Belgian expedition looking for meteorites preserved in the cold and dry environment of the South Pole. And they hit the jackpot: they found 635 fragments of micrometeorites. After coming back with the precious load, similar meteorite recovery expeditions and field campaigns focusing on micrometeorites continued in the following years, all equally successful. To date, they have found hundreds of pieces of meteorites and thousands of pieces of micrometeorites.

So what is the point of micrometeorites? Of all the material reaching Earth from space only a small part will survive the heating and shock experienced upon entry in the atmosphere. The large majority of this material, the micrometeorites, will rain on Earth as extraterrestrial particles of less than 2mm in size. Although meteorites in general provide us with essential information on the origin and evolution of the planets and the Solar System, micrometeorites, mostly originating from the most primitive objects still remaining in the Solar System, raise an even higher scientific interest. “Any information we can get from micrometeorites will complement the knowledge we have of meteorites, so it is really important to study them. We have a wide array of samples so that we can get the best possible picture of these materials”, explains Bastien Soens, who is doing his PhD on this subject.

Image: The team on the beamline. From left to right: Niels de Winter, Bastien Soens, Dip Banerjee, Stephen Bauers and Niels Collyns.
Credits: C. Argoud.

Identification of a mineral that until now was only present in meteroites

2017/08/032017/10/09

X-ray microdiffraction experiments were done to determine the crystalline structure of chladniite

Researchers from the Institute of Materials Science of Barcelona (ICMAB-CSIC), the Autonomous University of Barcelona (UAB), and the National University of Córdoba (Argentina), in collaboration with researchers of the ALBA Synchrotron, have identified a mineral in the region of Córdoba (Argentina), until now only observed in meteorites.

The study, published in European Journal of Mineralogy, affirms that the mineral is chladniite, a complex phosphate belonging to the fillowite group, which contains sodium, calcium, magnesium and iron, and has a trigonal structure. It has been found in a pegmatite, an igneous (magmatic) rock, formed from the slow cooling and solidification of magma.

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High-pressure experiments solve meteorite mystery

2017/06/072017/10/09

X-ray analysis reveals unexpected behaviour of silica minerals

With high-pressure experiments at DESY’s X-ray light source PETRA III and other facilities, a research team around Leonid Dubrovinsky from the University of Bayreuth has solved a long standing riddle in the analysis of meteorites from Moon and Mars. The study, published in the journal Nature Communications, can explain why different versions of silica can coexist in meteorites, although they normally require vastly different conditions to form. The results also mean that previous assessments of conditions at which meteorites have been formed have to be carefully re-considered.

The scientists investigated a silicon dioxide (SiO₂) mineral that is called cristobalite. „This mineral is of particular interest when studying planetary samples, such as meteorites, because this is the predominant silica mineral in extra-terrestrial materials,“ explains first author Ana Černok from Bayerisches Geoinstitut (BGI) at University Bayreuth, who is now based at the Open University in the UK. „Cristobalite has the same chemical composition as quartz, but the structure is significantly different,“ adds co-author Razvan Caracas from CNRS, ENS de Lyon.

>Read More

Picture: Credit: NASA/JPL/University of Arizona [Source]