Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Early planetesimal melting from an age of 4.5662 Gyr for differentiated meteorites


Long- and short-lived radioactive isotopes and their daughter products in meteorites are chronometers that can test models for Solar System formation1,2. Differentiated meteorites come from parent bodies that were once molten and separated into metal cores and silicate mantles. Mineral ages for these meteorites, however, are typically younger than age constraints for planetesimal differentiation3,4,5. Such young ages indicate that the energy required to melt their parent bodies could not have come from the most likely heat source6—radioactive decay of short-lived nuclides (26Al and 60Fe) injected from a nearby supernova—because these would have largely decayed by the time of melting. Here we report an age of 4.5662 ± 0.0001 billion years (based on Pb–Pb dating) for basaltic angrites, which is only 1 Myr younger than the currently accepted minimum age of the Solar System7 and corresponds to a time when 26Al and 60Fe decay could have triggered planetesimal melting. Small 26Mg excesses in bulk angrite samples confirm that 26Al decay contributed to the melting of their parent body. These results indicate that the accretion of differentiated planetesimals pre-dated that of undifferentiated planetesimals, and reveals the minimum Solar System age to be 4.5695 ± 0.0002 billion years.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Rent or buy this article

Get just this article for as long as you need it


Prices may be subject to local taxes which are calculated during checkout

Figure 1: Pb–Pb age and isotope data for angrites.
Figure 2: Timing of angrite magmatism and parent body (APB) accretion compared with upper age limits for accretion of chondrite parent bodies.


  1. Lissauer, J. J. Timescales for planetary accretion and the structure of the protoplanetary disc. Icarus 69, 249–265 (1987)

    Article  ADS  Google Scholar 

  2. Wasserburg, G. J. Isotopic abundances: inferences on solar system and planetary evolution. Earth Planet. Sci. Lett. 86(The 1986 Crafoord Lectures), 129–173 (1987)

    Article  ADS  CAS  Google Scholar 

  3. Yin, Q. et al. A short timescale for terrestrial planet formation from Hf–W chronometry of meteorites. Nature 418, 949–952 (2002)

    Article  ADS  CAS  Google Scholar 

  4. Kleine, T., Mezger, K., Münker, C., Palme, H. & Bischoff, A. 182Hf-182W isotope systematics of chondrites, eucrites, and martian meteorites: Chronology of core formation and early mantle differentiation in Vesta and Mars. Geochim. Cosmochim. Acta 68, 2935–2946 (2004)

    Article  ADS  CAS  Google Scholar 

  5. Lugmair, G. W. & Shukolyukov, A. Early solar system timescales according to 53Mn-53Cr systematics. Geochim. Cosmochim. Acta 62, 2863–2886 (1998)

    Article  ADS  CAS  Google Scholar 

  6. Urey, H. C. The cosmic abundances of potassium, uranium, and thorium and the heat balances of the Earth, the Moon, and Mars. Natl Acad. Sci. USA 41, 127–144 (1955)

    Article  ADS  CAS  Google Scholar 

  7. Amelin, Y., Krot, A. N., Hutcheon, I. D. & Ulyanov, A. A. Lead isotopic ages of chondrules and calcium-aluminium-rich inclusions. Science 297, 1678–1683 (2002)

    Article  ADS  CAS  Google Scholar 

  8. Mittlefehldt, D. W., Killgore, M. & Lee, M. T. Petrology and geochemistry of D'Orbigny and SAH99555, and the origin of angrites. Meteorit. Planet. Sci. 37, 345–369 (2002)

    Article  ADS  CAS  Google Scholar 

  9. Lugmair, G. W. & Galer, S. J. G. Age and isotopic relationships among the angrites Lewis Cliff 86010 and Angra dos Reis. Geochim. Cosmochim. Acta 56, 1673–1694 (1992)

    Article  ADS  CAS  Google Scholar 

  10. Jagoutz, E. et al. Cm?-U-Th-Pb isotopic evolution of the D'Orbigny angrite. 66th Annu. Meteorit. Soc. Meeting abstr. 5148 (2003).

  11. Nyquist, L. E., Shih, C. Y., Wiesmann, H. & Mikouchi, T. Fossil 26Al and 53Mn in D'Orbigny and Sahara 99555 and the timescale for angrite magmatism. Lunar Planet. Sci. Conf. XXXIV, abstr. 1388 (2003)

  12. Bizzarro, M., Baker, J. A. & Haack, H. Mg isotope evidence for contemporaneous formation of chondrules and refractory inclusions. Nature 431, 275–278 (2004)

    Article  ADS  CAS  Google Scholar 

  13. Young, E. D. et al. Supra-canonical 26Al/27Al and the residence time of CAIs in the solar protoplanetary disk. Science 308, 223–227 (2005)

    Article  ADS  CAS  Google Scholar 

  14. Stirling, C. H., Halliday, A. N. & Porcelli, D. In search of live 247Cm in the early solar system. Geochim. Cosmochim. Acta 69, 1059–1071 (2005)

    Article  ADS  CAS  Google Scholar 

  15. Glavin, D. P., Kubny, A., Jagoutz, E. & Lugmair, G. W. Mn-Cr isotope systematics of the D'Orbigny angrite. Meteorit. Planet. Sci. 39, 693–700 (2004)

    Article  ADS  CAS  Google Scholar 

  16. Kurat, G. et al. D'Orbigny: A non-igneous angritic achondrite? Geochim. Cosmochim. Acta 68, 1901–1921 (2004)

    Article  ADS  CAS  Google Scholar 

  17. Mittlefehldt, D. W. in Treatise of Geochemistry (ed. Davis, A. M.) Vol. 1,Ch. 11, 291–324 (Elsevier-Pergamon, Oxford, 2004)

    Google Scholar 

  18. Halliday, A. N. & Porcelli, D. In search of lost planets—the paleocosmochemistry of the inner solar system. Earth Planet. Sci. Lett. 192, 545–559 (2001)

    Article  ADS  CAS  Google Scholar 

  19. Gilmour, J. D. & Saxton, J. M. A time-scale of formation of the first solids. Phil. Trans. R. Soc. Lond. A 359, 2037–2048 (2001)

    Article  ADS  CAS  Google Scholar 

  20. Lugmair, G. W. & Shukolyukov, A. Early solar system events and timescales. Meteorit. Planet. Sci. 36, 1017–1026 (2001)

    Article  ADS  CAS  Google Scholar 

  21. Nyquist, L. et al. Manganese-chromium formation intervals for chondrules from the Bishunpur and Chainpur meteorites. Meteorit. Planet. Sci. 36, 911–938 (2001)

    Article  ADS  CAS  Google Scholar 

  22. Amelin, Y., Krot, A. & Twelker, E. Pb isotopic age of the CB chondrite Gujba, and the duration of the chondrule formation interval. Geochim. Cosmochim. Acta 68, abstr. E958 (2004)

  23. Kita, N. T. et al. Constraints on the origin of chondrules and CAIs from short-lived and long-lived radionuclides. Workshop on Chondrites and Protoplanetary Disks abstr. 9064 (2004)

  24. Kleine, T., Klaus, M., Herbert, P., Scherer, E. & Muenker, C. A new chronology for asteroid formation in the early solar system based on 182W systematics. Eos 85(47), Fall Meeting Suppl. abstr. P31C–04 (2004)

  25. Baker, J., Peate, D., Waight, T. & Meyzen, C. Pb isotopic analysis of standards and samples using a 207Pb-204Pb double spike and thallium to correct for mass bias with a double-focusing MC-ICPMS. Chem. Geol. 211, 275–303 (2004)

    Article  ADS  CAS  Google Scholar 

  26. LaTourrette, T. & Wasserburg, G. J. Mg diffusion in anorthite: implications for the formation of early solar system planetesimals. Earth Planet. Sci. Lett. 158, 91–108 (1998)

    Article  ADS  CAS  Google Scholar 

  27. Tatsumoto, M., Knight, R. J. & Allègre, C. J. Time differences in the formation of meteorites as determined from the ratio of lead-207 to lead-206. Science 180, 1278–1283 (1973)

    Article  ADS  Google Scholar 

Download references


Financial support for this project was provided by the Danish Lithosphere Centre (funded by the Danish National Science Foundation). L. Labenne is thanked for his efforts in finding SAH99555 and providing our angrite samples. C. Stirling provided us with a pre-print of her U isotope study of meteorites. NASA supplied the Martian meteorite EETA79001. V. Fernandes provided us with lunar meteorite NWA032. Y. Amelin is thanked for his feedback on an earlier version of this paper.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Joel Baker.

Ethics declarations

Competing interests

Reprints and permissions information is available at The authors declare no competing financial interests.

Supplementary information

Supplementary Methods

Description of analytical methods for Pb and Mg isotopic analysis. (DOC 32 kb)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Baker, J., Bizzarro, M., Wittig, N. et al. Early planetesimal melting from an age of 4.5662 Gyr for differentiated meteorites. Nature 436, 1127–1131 (2005).

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI:

This article is cited by


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing