Meteoritics

  • Article
    | Open Access

    Ultramafic olivine-rich achondrites provide insight into the missing mantle problem in the asteroid belt. The petrology and geochemistry of these samples suggests they are related to Vesta or the Vestoids.

    • Zoltan Vaci
    • , James M. D. Day
    •  & Andreas Pack
  • Article
    | Open Access

    Several scenarios exist to explain the origins of the organic matter found in carbonaceous chondrites. Here, the authors show laboratory experiments confirming that a significant portion of the soluble organic matter can originate from organic ices inherited from the dense molecular cloud.

    • G. Danger
    • , V. Vinogradoff
    •  & P. Schmitt-Kopplin
  • Article
    | Open Access

    The authors describe a dynamic surface instability between impacting materials, showing that a region of mixing grows between two media. The study implies that this can explain mixed compositions and textures in certain meteorites.

    • Avi Ravid
    • , Robert I. Citron
    •  & Raymond Jeanloz
  • Article
    | Open Access

    This manuscript tackles the origin of organic molecules in carbonaceous meteorites. Identifying hexamethylenetetramine in three carbonaceous meteorites, the authors propose formation from ammonia and formaldehyde by photochemical and thermal reactions in the interstellar medium, followed by the incorporation into planetary systems.

    • Yasuhiro Oba
    • , Yoshinori Takano
    •  & Shogo Tachibana
  • Article
    | Open Access

    The authors here analyse the petrology of the meteorite NWA 8321 (parent body Vesta). They find sulfidation processes of olivine suggesting metasomatism in the Vestan interior and a partial melting origin for the host noritic diogenite.

    • Ai-Cheng Zhang
    • , Noriyuki Kawasaki
    •  & Hisayoshi Yurimoto
  • Article
    | Open Access

    Fractured rocks of impact craters have been suggested to be suitable hosts for deep microbial communities on Earth, and potentially other terrestrial planets, yet direct evidence remains elusive. Here, the authors show that the Siljan impact structure is host to long-term deep methane-cycling microbial activity.

    • Henrik Drake
    • , Nick M. W. Roberts
    •  & Mats E. Åström
  • Article
    | Open Access

    Cyanide is thought to be crucial for the origin of life. Here, the authors showed that iron cyanocarbonyl complexes are present in meteorites and propose that these compounds were a source of free cyanide on early Earth and served as precursors to the active sites of ancient hydrogenases.

    • Karen E. Smith
    • , Christopher H. House
    •  & Michael P. Callahan
  • Article
    | Open Access

    A unified model for the formation of martian rock types is required to understand Mars’s formation and evolution. Here the authors show that nakhlite and chassignite meteorites originate from melting of metasomatized depleted mantle lithosphere, whereas shergottite melts originate from deep plume sources.

    • James M. D. Day
    • , Kimberly T. Tait
    •  & Clive R. Neal
  • Article
    | Open Access

    Achondritic meteorites can record volcanism and crust formation on planetesimals in the early Solar System. Here, the authors date the Northwest Africa 11119 meteorite with an Al-Mg age of 4564.8 ± 0.3 Ma indicating that this is the earliest evidence of silicic volcanism in the Solar System to date.

    • Poorna Srinivasan
    • , Daniel R. Dunlap
    •  & Francis M. McCubbin
  • Article
    | Open Access

    Ureilites are a type of meteorite that are believed to be derived from a parent body that was impacted in the early solar system. Here, the authors analyse inclusions within diamonds from a ureilite meteorite and find that they must have formed at above 20 GPa suggesting the parent body was Mercury- to Mars-sized.

    • Farhang Nabiei
    • , James Badro
    •  & Philippe Gillet
  • Article
    | Open Access

    Our understanding of shock metamorphism and thus the collision of planetary bodies is limited by a dependence on ex situ analyses. Here, the authors perform in situ analysis on shocked-produced densified glass and show that estimates of impactor size based on traditional techniques are likely inflated.

    • A. E. Gleason
    • , C. A. Bolme
    •  & W. L. Mao
  • Article
    | Open Access

    Mars hosts the solar system’s largest volcanoes, but their formation rates remain poorly constrained. Here, the authors have measured the crystallization and ejection ages of meteorites from a Martian volcano and find that its growth rate was much slower than analogous volcanoes on Earth.

    • Benjamin E. Cohen
    • , Darren F. Mark
    •  & Caroline L. Smith
  • Article
    | Open Access

    Meteorites may unlock the history of the early solar system. Here, the authors find, through Ca-Fe-rich secondary phases, that the distinction between reduced and oxidized CV chondrites is invalid; therefore, CV3 chondrites are asteroid fragments that percolated heterogeneously via porous flow of hydrothermal fluid.

    • Clément Ganino
    •  & Guy Libourel
  • Article
    | Open Access

    Identifying the original impactor from craters remains challenging. Here, the authors use chromium and oxygen isotopes to indicate that the Zhamanshin astrobleme impactor was a carbonaceous chrondrite by demonstrating that depleted 17O values are due to exchange with atmospheric oxygen.

    • Tomáš Magna
    • , Karel Žák
    •  & Zdeněk Řanda
  • Article
    | Open Access

    Oxygen contained within cosmic spherules is sourced from the atmosphere, making micrometeorites a possible archive for past atmospheric conditions. Here, Packet al. compare the isotopic composition of oxygen in cosmic spherules from Antarctica with that of the troposphere, and validate the value of this archive.

    • Andreas Pack
    • , Andres Höweling
    •  & Luigi Folco
  • Article
    | Open Access

    Constraining the timing of crustal processes and impact events remains challenging. Here, the authors show that atom probe tomography can produce highly accurate U-Pb isotopic age constraints in baddeleyite crystals, which is a common phase in terrestrial, Martian, Lunar and asteroidal materials.

    • L. F. White
    • , J. R. Darling
    •  & I. Martin
  • Article
    | Open Access

    The high amount of L-type chondrites discovered in Ordovician sediments has previously been linked with the Great Ordovician Biodiversification Event. But here, Lindskoget al. present new zircon ages that date the chondrite dispersion to 468.0±0.3 Ma, showing that the two events may be unrelated.

    • A. Lindskog
    • , M. M. Costa
    •  & M. E. Eriksson
  • Article
    | Open Access

    Meteorites falling on Earth today are believed to represent 100–150 parent bodies. Within 470 Myr ago sediments at a limestone quarry in Sweden, Schmitz et al. have found and identified a new type of meteorite based on chromium and oxygen isotopes sourced from a previously unknown parental body.

    • B. Schmitz
    • , Q. -Z. Yin
    •  & G. R. Huss
  • Article
    | Open Access

    Collection data suggest the proportion of iron-based meteorites recovered from Antarctica is significantly lower than the rest of the world. Here, the authors propose a mechanism to explain this discrepancy, showing that iron meteorites heated by solar energy can move down through the ice, not to re-emerge.

    • G. W. Evatt
    • , M. J. Coughlan
    •  & I. D. Abrahams
  • Article
    | Open Access

    Collisions in the early Solar System affected the final composition of the terrestrial planets, and enstatite chondrites (EC) are thought to represent the primordial Earth’s precursors. Here, the authors show that differences between Earth and EC are due to impact erosion of >15% of the early Earth’s mass.

    • Asmaa Boujibar
    • , Denis Andrault
    •  & Julien Monteux
  • Article |

    The first-reported natural quasicrystal, found in the meteorite Khatyrka, has posed many questions regarding the extraterrestrial processes that led to its formation. Here, the authors suggest how the metallic Al- and Cu-bearing phases formed and report the discovery of other new minerals.

    • Lincoln S. Hollister
    • , Luca Bindi
    •  & Paul J. Steinhardt
  • Article |

    Few high-pressure polymorphs have been found from lunar meteorites even though the moon has experienced heavy meteorite bombardment. This study presents evidence of a high-pressure polymorph of silica—seifertite—from a lunar meteorite; a record of an intense planetary collision on the moon ~2.7 Ga ago.

    • Masaaki Miyahara
    • , Shohei Kaneko
    •  & Naohisa Hirao
  • Article |

    High-pressure minerals in meteorites reflect the conditions prevailing when they were excavated and launched from their parent bodies. Tissint—a recent Martian meteorite—contains an unusual number of large high-pressure minerals, suggesting excavation from an impact of larger magnitude than for previous Martian samples.

    • Ioannis P. Baziotis
    • , Yang Liu
    •  & Lawrence A. Taylor
  • Article |

    Dating the age of meteorites can tell us when asteroids formed, but uncertainty remains in the Mn–Cr chronometry. This study presents a method for improving Mn/Cr determination and reports an age of 4,563.4 million years ago for carbonates in CM chondrites, which is younger than previous estimates.

    • Wataru Fujiya
    • , Naoji Sugiura
    •  & Yuji Sano