**Fig. 1.** Cumulative plot of the time spectrum of martian meteorite delivery.
Dashed line and heavy squares: CRE data from the martian meteorites. Dotted line:
Collisionless N-body model, nu_{infinity} = 1 km/s launches from Mars. Solid line:
Inclusion of a 2-Myr collisonal half-life for meteoroids while in the asteroid belt (Q > 2.1 AU).
The model provides a good fit to the data. Errors on the CRE ages are about 10-30%.