  Measurements of long-lived radioisotopes provide a means, completely
independent of other observational channels, to draw conclusions about
near-Earth supernovae (SNe) and thus the origin of the Local Bubble (LB). First
and foremost in this context is 60Fe, which has already been detected across
the Earth and on the Moon. Using Gaia EDR3, we identified 14 SN explosions,
with 13 occurring in UCL/LCC, and one in V1062 Sco, all being subgroups of the
Sco-Cen OB association. The timing of these explosions was obtained by us
through interpolation of rotating stellar evolution tracks via the initial
masses of the already exploded massive stars. We further developed a new Monte
Carlo-type approach for deriving the trajectories of the SN progenitors. We
then performed 3D hydrodynamic simulations based on these initial conditions to
explore the evolution of the LB in an inhomogeneous local interstellar medium
and the transport of radioisotopes to Earth. The simulations include the
stellar winds from the SN progenitors and additional radioisotopes (26Al, 53Mn,
and 244Pu) besides 60Fe. We find that (i) our simulations are consistent with
measurements of 60Fe, in particular, a peak 2-3 Myr before present, as well as
26Al, 53Mn, and 244Pu data, (ii) stellar winds contribute to the distribution
of radioisotopes and also to the dynamics of the LB, (iii) the solar system
(SS) entered the LB about 4.6 Myr ago, and (iv) the measured recent influx of
60Fe can be naturally explained by turbulent radioisotopic transport. Our
simulations not only support the recent hypothesis that the LB triggered star
formation in the solar vicinity through its expansion, but also suggest that
the second, separate 60Fe peak measured at 6-9 Myr ago was generated by the
passage of the SS through a neighboring superbubble (SB), possibly the
Orion-Eridanus SB, prior to its current residence in the LB.
