Researchers at Lawrence Livermore use extraterrestrial materials and state-of-the-art equipment to unravel the history of the solar system.
Answering fundamental questions
Cosmochemistry is the study of extraterrestrial materials—samples returned by space flight missions as well as meteorites and their components—with the goal of understanding the origin and evolution of the solar system and our cosmic neighborhood. The research includes the full history of the solar system, from before the protoplanetary disk began to coalesce and the Sun formed, up until present.
Decades of funding and research have helped establish cosmochemistry research at Livermore, which is one of the world’s foremost centers of research on the origin and evolution of the solar system. Here, we look to answer big questions:
- How did the Sun and our solar system form, and how long did this take?
- What types of stars and what materials from these stars contributed to the birth environment of the solar system?
- How and when do planets form cores, mantles, crusts, and atmospheres?
- How did Earth become habitable, and where did its water come from?
- What is the impact history of the solar system?
- Is there something unique about the solar system compared to extrasolar planetary systems that enabled life to develop here?
Cosmochemistry work at LLNL falls into several disciplines:
Early solar system processes that investigate the origin and evolution of the first solid matter
Primordial planetary geology that is concerned with the period of time between accretion and formation of planetary cores, mantles, crusts, and atmospheres
Geologic evolution of differentiated bodies until the present
Nucleosynthetic processes contributing to the galactic abundances of the elements
Leveraging state-of-the-art equipment
Livermore’s cosmochemistry research is facilitated by world-class onsite capabilities, including several forms of mass spectrometry, such as inductively coupled plasma, thermal ionization, noble gas, resonance ionization, and secondary ion mass spectrometry. This includes a nanometer-scale secondary ion mass spectrometer (nanoSIMS)—one of less than two dozen such instruments in the world—that permits us to measure isotopic variations that exist at the nanoscale.
In addition to measuring inherent isotopic variation to study sample provenance, chronology is a major thrust of our research at LLNL. Radioactive decay of isotopes from a variety of elements provides the potential to determine the age of a material anywhere from months to billions of years old. By measuring the abundances of parent and daughter isotopes in samples with Livermore’s extremely accurate mass spectrometers, we can measure the age of planetary and meteoritic materials with incredible precision, even with limited amounts of materials. We have dated objects such as the first solids to form in the solar system, tiny bits of cometary material collected during NASA’s Stardust mission, meteorites that formed beyond the orbit of Jupiter, rocks ejected from Mars by violent impacts, and lunar samples returned by the Apollo missions.
Our researchers are applying these techniques to material collected on asteroid return missions to gain comprehensive insight into what type of material the solar system formed from and how it has evolved since its formation. Livermore was awarded samples from the asteroid Ryugu (Hayabusa2 mission, landed December 2020) and the asteroid Bennu (OSRIS-Rex mission, landing September 2023).
Using these measurement tools and techniques, we have uncovered:
- The collapse of the molecular cloud that formed the Sun and solar system happened rapidly, with the bulk of the material that formed the Sun accreting in less than 200,000 years.
- Chronologic measurements of numerous lunar samples suggest Earth’s moon differentiated around about 4.35 billion years ago.
- Jupiter formed very early in solar system history, and its formation truncated the disk into inner and outer solar system reservoirs.
- Model ages of martian samples indicate Mars underwent differentiation about 4.50 billion years ago.
- The topographic and geophysical divide between the heavily cratered southern highlands and smoother plains of the northern lowlands of Mars likely formed within the first 100 million years of planetary history.
- The materials from which Earth and the Moon formed were depleted in volatile elements, meaning Earth’s water is either primordial or arrived largely without other volatile components.
- The timescale of dust formation following supernova explosions is longer than expected and helps explain some of the isotopic compositions of materials that contributed to the birth environment of the solar system.
Techniques and tools serving a dual purpose
The analytical, methodological, and philosophical overlap with cosmochemistry and nuclear forensics allows us to answer fundamental research questions while contributing to the Laboratory’s security missions. Nuclear forensics is central to these missions, and cosmochemical work has been key to developing novel techniques to measure isotopes that can provide clues to the origin of illicit nuclear materials that might be diverted for use in weapons of mass destruction. In fact, many of the same techniques used for cosmochemistry research also apply to constraining the origins of nuclear forensics samples.
|James Bryson||Department of Earth Sciences||Oxford University|
|Richard Carlson||Department of Terrestrial Magnetism||Carnegie Institute, Washington|
|James Connelly||University of Copenhagen|
|Thorsten Kleine||Max Planck Institute|
|Charles Shearer||Institute of Meteoritics||University of New Mexico|
|Meenakshi Wadhwa||Department of Earth and Space Exploration||Arizona State University|
|Manavi Jadhav||Department of Physics||University of Louisiana at Lafayette|
|Edward Young||Department of Earth, Planetary, and Space Sciences||University of California, Los Angeles|
|Reto Trappitsch||School of Physics||Brandeis University|
|Chelsea Willett||International Atomic Energy Agency|
Disk transport rates from Ti isotopic signatures of refractory inclusions | Meteoritics & Planetary Science, 2022
J. Render, J.F.J. Bryson, S. Ebert, G.A. Brennecka
Solar System evolution and terrestrial planet accretion determined by Zr isotopic signatures of meteorites | Earth & Planetary Science Letters, 2022
J. Render, G.A. Brennecka, C. Burkhardt, T. Kleine
The gallium isotopic composition of the Moon | Earth and Planetary Science Letters, 2022
J. Wimpenny, L. Borg, and C.K.I. Sio
The origin of volatile elements in the Earth–Moon system | Proceedings of the National Academy of Sciences, 2022
L.E. Borg, G.A. Brennecka, T. S. Kruijer
Titanium isotope systematics of refractory inclusions: Echoes of molecular cloud heterogeneity | Geochimica Cosmochimica Acta, 2022
Q.R. Shollenberger, J. Render, M.K. Jordan, K.A. McCain, S. Ebert, A. Bischoff, T. Kleine, E.D. Young
Tungsten and molybdenum isotopic evidence for an impact origin of pallasites | Earth and Planetary Science Letters, 2022
T. S. Kruijer, C. Burkhardt, L. E. Borg, T. Kleine
Constraints on chondrule generation, disk dynamics, and asteroid accretion from the compositions of carbonaceous meteorites | The Astrophysical Journal, 2021
J.F.J. Bryson and G.A. Brennecka
Fossil records of early solar irradiation and cosmolocation of the CAI factory: A reappraisal | Science Advances, 2021
D.V. Bekaert, M. Auro, Q.R. Shollenberger, M.-C. Liu, H. Marschall, K.W. Burton, B. Jacobsen, G.A. Brennecka, G.J. MacPherson, R. von Mutius, A. Sarafian, S.G. Nielsen
Isotopic signatures as tools to reconstruct the primordial architecture of the Solar System | Earth and Planetary Science Letters, 2021
J. Render and G.A. Brennecka
Astronomical context of Solar System formation from molybdenum isotopes in meteorite inclusions | Science, 2020
G.A. Brennecka, C. Burkhardt, G. Budde, T.S. Kruijer, F. Nimmo, T. Kleine
Constraining the behavior of gallium isotopes during evaporation at extreme temperatures | Geochimica et Cosmochimica Acta, 2020
J. Wimpenny, N. Marks, K. Knight, L. Borg, J. Badro, and F. Ryerson
Lifetimes of interstellar dust from cosmic ray exposure ages of presolar silicon carbide | Proceedings of the National Academy of Sciences, 2020
P.R. Heck, J. Greer, L. Kööp, R. Trappitsch, F. Gyngard, H. Busemann, C. Maden, J.N. Ávila, A.M. Davis, R. Wieler
The formation and evolution of the Moon’s crust inferred from the Sm-Nd isotopic systematics of highlands rocks | Geochimica et Cosmochimica Acta, 2020
L.E. Borg, W. S. Cassata, J. Wimpenny, A. M. Gaffney, C. K. Shearer
The great isotopic dichotomy of the early Solar System | Nature Astronomy, 2020
T.S. Kruijer, T. Kleine, L.E. Borg
The timing of lunar solidification and mantle overturn recorded in ferroan anorthosite | Earth and Planetary Science Letters, 2020
C. K. Sio, L. E. Borg, and W. S. Cassata
Isotopes of Barium as a Chronometer for Supernova Dust Formation | The Astrophysical Journal, 2019
U. Ott, T. Stephan, P. Hoppe, M.R. Savina
Isotopic evidence for a young magma ocean | Earth and Planetary Science Letters, 2019
L.E. Borg, A.M. Gaffney, T.K. Kruijer, N.A. Marks, C.K. Sio, J. Wimpenny
Age of Jupiter inferred from the distinct genetics and formation times of meteorites | Proceedings of the National Academy of Sciences, 2017
T.S. Kruijer, C. Burkhardt, G. Budde, T. Kleine
A nucleosynthetic origin of the Earth’s anomalous 142Nd composition | Nature, 2016
C. Burkhardt, L.E. Borg, G.A. Brennecka, Q.R. Shollenberger, N. Dauphas, T. Kleine
Evidence for supernova injection into the solar nebula and the decoupling of r-process nucleosynthesis | Proceedings of the National Academy of Sciences, 2013
G.A. Brennecka, L.E. Borg, M. Wadhwa