title: Abundant ammonia and nitrogen-rich soluble organic matter in samples from asteroid (101955) Bennu
Creators: name: Glavin, Daniel P.
name: Dworkin, Jason P.
name: Alexander, Conel M. O’D
name: Aponte, José C.
name: Baczynski, Allison A.
name: Barnes, Jessica J.
name: Bechtel, Hans A.
name: Berger, Eve L.
name: Burton, Aaron S.
name: Caselli, Paola
name: Chung, Angela H.
name: Clemett, Simon J.
name: Cody, George D.
name: Dominguez, Gerardo
name: Elsila, Jamie E.
name: Farnsworth, Kendra
name: Foustoukos, Dionysis I.
name: Freeman, Katherine H.
name: Furukawa, Yoshihiro
name: Gainsforth, Zack
name: Graham, Heather V.
name: Grassi, Tommaso
name: Giuliano, Barbara Michela
name: Hamilton, Victoria E.
name: Haenecour, Pierre
name: Heck, Philipp R.
name: Hofmann, Amy E.
name: House, Christopher H.
name: Huang, Yongsong
name: Kaplan, Hannah H.
name: Keller, Lindsay P.
name: Kim, Bumsoo
name: Koga, Toshiki
name: Liss, Michael
name: McLain, Hannah L.
name: Marcus, Matthew A.
name: Matney, Mila
name: McCoy, Timothy J.
name: McIntosh, Ophélie M.
name: Mojarro, Angel
name: Naraoka, Hiroshi
name: Nguyen, Ann N.
name: Nuevo, Michel
name: Nuth, Joseph A.
name: Oba, Yasuhiro
name: Parker, Eric T.
name: Peretyazhko, Tanya S.
name: Sandford, Scott A.
name: Santos, Ewerton
name: Schmitt-Kopplin, Philippe
name: Seguin, Frederic
name: Simkus, Danielle N.
name: Shahid, Anique
name: Takano, Yoshinori
name: Thomas-Keprta, Kathie L.
name: Tripathi, Havishk
name: Weiss, Gabriella
name: Zheng, Yuke
name: Lunning, Nicole G.
name: Righter, Kevin
name: Connolly, Harold C.
name: Lauretta, Dante S.
Publisher: name: Springer Nature
Year: 2025
Subjects: subject: Asteroids
subject: comets and Kuiper belt
subject: Astrobiology

description: Organic matter in meteorites reveals clues about early Solar System chemistry and the origin of molecules important to life, but terrestrial exposure complicates interpretation. Samples returned from the B-type asteroid Bennu by the Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer mission enabled us to study pristine carbonaceous astromaterial without uncontrolled exposure to Earth’s biosphere. Here we show that Bennu samples are volatile rich, with more carbon, nitrogen and ammonia than samples from asteroid Ryugu and most meteorites. Nitrogen-15 isotopic enrichments indicate that ammonia and other N-containing soluble molecules formed in a cold molecular cloud or the outer protoplanetary disk. We detected amino acids (including 14 of the 20 used in terrestrial biology), amines, formaldehyde, carboxylic acids, polycyclic aromatic hydrocarbons and N-heterocycles (including all five nucleobases found in DNA and RNA), along with ~10,000 N-bearing chemical species. All chiral non-protein amino acids were racemic or nearly so, implying that terrestrial life’s left-handed chirality may not be due to bias in prebiotic molecules delivered by impacts. The relative abundances of amino acids and other soluble organics suggest formation and alteration by low-temperature reactions, possibly in NH3-rich fluids. Bennu’s parent asteroid developed in or accreted ices from a reservoir in the outer Solar System where ammonia ice was stable.