Lifetime of the solar nebula constrained by meteorite paleomagnetism.
A key stage in planet formation is the evolution of a gaseous and magnetized solar nebula. However, the lifetime of the nebular magnetic field and nebula are poorly constrained. We present paleomagnetic analyses of volcanic angrites demonstrating that they formed in a near-zero magnetic field (<0.6 microtesla) at 4563.5 ± 0.1 million years ago, ~3.8 million years after solar system formation. This indicates that the solar nebula field, and likely the nebular gas, had dispersed by this time. This sets the time scale for formation of the gas giants and planet migration. Furthermore, it supports formation of chondrules after 4563.5 million years ago by non-nebular processes like planetesimal collisions. The core dynamo on the angrite parent body did not initiate until about 4 to 11 million years after solar system formation.
Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA. huapei@mit.edu.
Huapei
0000-0003-1676-3494
H
Wang
Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
Benjamin P
BP
Weiss
Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, USA.
Xue-Ning
0000-0003-1172-3039
XN
Bai
Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
Brynna G
BG
Downey
National Synchrotron Light Source-II, Brookhaven National Laboratory, Upton, NY, USA.
Jun
J
Wang
National Synchrotron Light Source-II, Brookhaven National Laboratory, Upton, NY, USA.
Jiajun
J
Wang
Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
Clément
0000-0001-9970-0864
C
Suavet
Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
Roger R
RR
Fu
Museu Nacional, Rio de Janeiro, Brazil.
Maria E
0000-0003-2896-1105
ME
Zucolotto