Lub hnub qub Bennu yog lub hnub qub carbonaceous asteroid uas muaj pob zeb thiab hmoov av los ntawm kev yug los ntawm lub hnub ci. Nws tau xav tias kev kawm ntawm ib qho piv txwv los ntawm lub hnub qub Bennu sau ncaj qha rau hauv qhov chaw yuav ua rau pom lub ntiaj teb li cas tau tsim thiab lub neej pib li cas hauv ntiaj teb. OSIRIS-REx, NASA thawj lub hnub qub qauv rov qab los lub hom phiaj tau pib hauv 2016 mus ze-Lub Ntiaj Teb asteroid Bennu. Nws tau xa cov qauv tshuaj ntsiav rau lub ntiaj teb rau 24 Cuaj hlis 2023. Kev tshawb fawb tob txog cov qauv xa rov qab tam sim no tau ua tiav, thiab cov txiaj ntsig tau tshaj tawm rau 29 Lub Ib Hlis 2025. Cov qauv xa rov qab muaj ntau cov ammonia thiab nitrogen-nplua nuj soluble. organic teeb meem uas yog qhov tseem ceeb rau lub neej hauv ntiaj teb. Cov organic tebchaw tseem ceeb hauv cov qauv yog cov amino acids (xws li 14 ntawm 20 pom nyob rau hauv lub neej hauv lub ntiaj teb), amines, formaldehyde, carboxylic acids, polycyclic aromatic hydrocarbons thiab N-heterocycles (nrog rau tag nrho tsib nucleobases pom hauv DNA thiab RNA. nyob ntiaj teb). Tsis tas li ntawd, cov qauv kuj tseem muaj cov ntxhia ntsev tsim vim evaporation ntawm brine uas tshwm sim thaum ntxov hauv niam txiv lub cev ntawm lub hnub qub Bennu, qhia tias cov dej ntsev hauv keeb kwm yav dhau los tuaj yeem ua qhov nruab nrab rau kev sib cuam tshuam tshuaj lom neeg ntawm cov molecules kuaj pom hauv cov qauv. Kev tshawb nrhiav lub tsev blocks rau lub neej thiab ntsev cov zaub mov hauv cov qauv pristine sau nyob rau hauv qhov chaw ncaj qha los ntawm lub hnub qub Bennu thiab kawm nyob rau hauv kev sib kis-tswj kev ntsuas muab kev ntseeg siab rau lub tswv yim tias cov precursors rau kev tshwm sim ntawm lub neej tau dav nyob rau hauv lub hnub qub thaum ntxov. Yog li ntawd, muaj qee qhov ua tau ntawm lub neej tshwm sim ntawm lwm lub ntiaj teb lossis lawv cov satellites ntuj. Cov xwm txheej ntawm lub hnub qub Bennu kuj yog tus sawv cev ntawm lub ntiaj teb keeb kwm thaum ntxov. Nws muab ib lub tswv yim hais txog cov khoom xyaw uas muaj nyob rau hauv lub hnub ci system ua ntej tshwm sim ntawm lub neej nyob rau hauv lub ntiaj teb no.
Asteroid Bennu yog ib qho ze-Earth orbit asteroid xav tau tsim txog 4.5 billion xyoo dhau los nyob rau theem pib ntawm keeb kwm ntawm lub hnub ci. Nws yog hom B, carbonaceous asteroid uas muaj pob zeb thiab hmoov av los ntawm kev yug los ntawm lub hnub ci. Nws tau xav tias Bennu kuj tseem tuaj yeem muaj cov khoom uas muaj cov molecules uas muaj nyob thaum lub neej tsim hauv ntiaj teb. Asteroids nplua nuj nyob rau hauv cov organics tau xav tias tau ua lub luag haujlwm hauv catalysing lub neej hauv ntiaj teb. Txoj kev kawm ntawm cov qauv coj los ntawm lub hnub qub Bennu tau xav tias yuav pov lub teeb ntawm lub ntiaj teb li cas tau tsim thiab lub neej pib li cas. NASA lub hom phiaj OSIRIS-REx tsom rau qhov no.
Lub asteroid qauv xa rov qab lub hom phiaj OSIRIS-REx ( Keeb Kwm, Spectral Txhais Lus, Kev Qhia Txog Kev Tshawb Fawb thiab Kev Ruaj Ntseg - Regolith Explorer) tau pib mus rau lub ntiaj teb ze-Earth asteroid Bennu rau 8 Cuaj hlis 2016. Nws tau sau cov qauv ntawm pob zeb thiab hmoov av los ntawm qhov chaw ntawm lub hnub qub. Hnub tim 20 Lub Kaum Hli 2020 thiab pib nws txoj kev rov qab los rau lub ntiaj teb thaum Lub Tsib Hlis 10, 2021. Mus ncig rau ob xyoos thiab ib nrab xyoo hauv nws rov qab taug kev, thaum lub Cuaj Hlis 24, 2023, nws tso tawm cov tshuaj ntsiav uas muaj pob zeb thiab hmoov av piv txwv sau los ntawm lub hnub qub Bennu mus rau hauv lub ntiaj teb huab cua thiab txuas ntxiv nws txoj kev taug mus ntxiv mus rau lwm lub ntiaj teb asteroid Apophis raws li OSIRIS-APEX lub hom phiaj.
Cov tshuaj ntsiav uas muaj cov qauv ntawm pob zeb thiab hmoov av hnyav txog 250 grams uas tau sau los ntawm lub hnub qub Bennu tau tsaws hauv lub ntiaj teb kom nyab xeeb ntawm Utah qhov chaw ze Salt Lake City hauv Tebchaws Meskas tib hnub rau hnub Sunday 24 Lub Cuaj Hli 2023. Cov qauv rov qab los tam sim no tau kawm txog qhov tob. , thiab cov txiaj ntsig tau tshaj tawm rau 29 Lub Ib Hlis 2025.
Kev soj ntsuam ntawm cov qauv xa rov qab los ntawm ib pab neeg tshawb fawb tau qhia tias muaj ntau ntawm ammonia thiab nitrogen-nplua nuj soluble organic teeb meem uas yog qhov tseem ceeb rau lub neej hauv ntiaj teb. Cov organic tebchaw kuaj pom nyob rau hauv cov qauv yog cov amino acids (xws li 14 ntawm 20 pom nyob rau hauv lub nyob systems ntawm lub ntiaj teb), amines, formaldehyde, carboxylic acids, polycyclic aromatic hydrocarbons thiab N-heterocycles (nrog rau tag nrho tsib nucleobases pom nyob rau hauv DNA thiab RNA ntawm Lub ntiaj teb uas siv los khaws thiab xa cov ntaub ntawv caj ces rau cov xeeb ntxwv). Kev nplua nuj ntawm ammonia hauv cov qauv yog qhov tseem ceeb vim tias ammonia tuaj yeem cuam tshuam nrog formaldehyde los tsim cov amino acids hauv txoj cai. Interestingly, cov amino acids nrog chirality nyob rau hauv cov qauv ntawm Bennu yog racemic los yog sib npaug sib xyaw ntawm ob sab laug- thiab sab xis-tes versions. Hauv ntiaj teb, cov kab ke ua neej tsuas yog muaj cov ntawv sab laug. Tej zaum, cov amino acids nyob rau hauv lub ntiaj teb thaum ntxov yog racemic sib tov thiab sab laug-tes chirality ntawm lub neej nyob rau hauv lub ntiaj teb no evolved tom qab vim ib co tsis paub vim li cas.
Tsis tas li ntawd, lwm pab pawg tshawb fawb pom cov ntsev ntsev hauv cov qauv uas suav nrog sodium-bearing phosphates thiab sodium-nplua nuj carbonates, sulphates, chlorides thiab fluorides. Cov ntsev no tsim los ntawm evaporation ntawm brine uas tshwm sim thaum ntxov hauv niam txiv lub cev ntawm lub hnub qub Bennu. Cov dej ntsev hauv keeb kwm yav dhau los tuaj yeem ua qhov nruab nrab tsim nyog rau kev sib cuam tshuam tshuaj lom neeg ntawm cov molecules kuaj pom hauv cov qauv.
Cov organic teeb meem thiab cov ntxhia ntsev tau raug kuaj pom ua ntej nyob rau hauv cov meteorites, tab sis raug rau lub ntiaj teb huab cua cuam tshuam kev txhais lus raws li lawv tau yooj yim puas los yog hloov mus rau hauv lub ntiaj teb ib puag ncig.
Kev tshawb nrhiav lub tsev thaiv rau lub neej thiab cov evaporites (cov ntsev ntsev tsim tom qab evaporation ntawm brine) nyob rau hauv cov qauv pristine sau nyob rau hauv qhov chaw ncaj qha los ntawm lub asteroid Bennu thiab kawm nyob rau hauv kev sib kis-tswj ntsuas yog tshiab. Qhov no ua rau muaj kev ntseeg siab rau lub tswv yim tias cov precursors rau qhov tshwm sim ntawm lub neej tau dav dav nyob rau hauv lub hnub ci thaum ntxov. Yog li ntawd, muaj qee qhov ua tau ntawm lub neej tshwm sim ntawm lwm lub ntiaj teb lossis lawv cov satellites ntuj. Cov xwm txheej ntawm lub hnub qub Bennu kuj yog tus sawv cev ntawm lub ntiaj teb keeb kwm thaum ntxov. Nws muab ib lub tswv yim hais txog cov khoom xyaw uas muaj nyob rau hauv lub hnub ci system ua ntej tshwm sim ntawm lub neej nyob rau hauv lub ntiaj teb no.
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References:
- Glavin, DP, et al. 2025. Muaj ntau ammonia thiab nitrogen-nplua nuj soluble organic teeb meem hauv cov qauv ntawm asteroid (101955) Bennu. Nat Astron. Published: 29 January 2025. DOI: https://doi.org/10.1038/s41550-024-02472-9
- McCoy, TJ, et al. 2025. Ib qho evaporite ib ntus los ntawm cov brine thaum ub sau tseg hauv Bennu cov qauv. Xwm Txheej 637, 1072–1077. Published: 29 January 2025. DOI: https://doi.org/10.1038/s41586-024-08495-6
- NASA. Xov xwm - NASA's Asteroid Bennu Sample nthuav tawm cov khoom xyaw ntawm lub neej. Tshaj tawm 29 Lub Ib Hlis 2025. Muaj nyob ntawm https://www.nasa.gov/news-release/nasas-asteroid-bennu-sample-reveals-mix-of-lifes-ingredients/
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Tshooj cai:
- NASA's OSIRIS-REx Lub Hom Phiaj nqa cov qauv ntawm lub hnub qub Bennu mus rau lub ntiaj teb (26 Lub Cuaj Hli 2023).
- nyob ze-Lub Ntiaj Teb asteroid 2024 BJ kom ze tshaj plaws rau lub ntiaj teb (26 Lub Ib Hlis 2024)
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, amines, formaldehyde, carboxylic acids, polycyclic aromatic hydrocarbons and N-heterocycles (including all five nucleobases found in DNA and RNA on Earth). Further, the sample also had salt minerals formed due to evaporation of brine that existed early in the parent body of the asteroid Bennu, suggesting salt water in the early history could have served as a medium for chemical interaction between the molecules detected in the sample. Detection of building blocks for life and salt minerals in the pristine sample collected in space directly from the asteroid Bennu and studied under contamination-control measures gives credence to the idea that the precursors for the emergence of life were widespread in the early solar system. Therefore, there is some possibility of life emerging on other planets or their natural satellites. Conditions at the asteroid Bennu is also a representative of Earth’s early history. It gives an idea about the ingredients present in the solar system before emergence of life on Earth.){kind=link}