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tokens: measured ratios range between 1.04 ± 0.05 for the meteorite Malakal and 4.56 ± 0.38 for the meteorite Jilin. The ratio for Jilin is not representative because this meteorite experienced a complex exposure history and 26 Al is not in saturation, making the 22 Na/ 26 Al ratio too high (Begemann et al. 1985 ). Ignoring Jilin for the discussion, the upper limit is reduced to 2.48 for the meteorite Dhajala. Again, excluding Jilin, the average value for the 22 Na/ 26 Al ratio for the studied meteorites is 1.46 ± 0.27. Both the range and the average value are in agreement with the model predictions. In addition, the 22 Na/ 26 Al ratios for a variety of ordinary chondrites studied by Bhandari et al. ( 1994 ) range between ∼1 and ∼2.3, again in agreement with the model predictions. For the meteorite Chelyabinsk, Alexeev et al. ( 2019 ) give 22 Na/ 26 Al ratios of 1.4 ± 1.2 for a depth larger than 100 cm, 2.42 ± 0.17 at a depth of 10–50 cm, and of 2.53 ± 0.24 for depths of 50–100 cm. For the Košice meteorite, the same authors measured 1.45 ± 0.20 for depths below 10 cm and 1.52 ± 0.21 for depths between 10 and 50 cm. All values are well within the range of the predicted 22 Na/ 26 Al ratios we modeled for an L-chondrite with a radius of 45 cm (see Figure 6 ). The data for meteorites indicate that the 22 Na/ 26 Al production rate ratios vary enough to be useful for studies on the temporal variability of the solar modulation function. For the following, more qualitative discussion, we use the reconstruction of the solar modulation function given by Usoskin et al. ( 2017 ) shown in Figure 2 . Because the data are for 1 au, we adjusted them to the meteoroid orbits at ∼3 au by simply subtracting ΔΦ = 60 MeV, which we determined above as the best value for the long-term average gradient in the inner solar system (see also Section 2.3 ). Note that this procedure is surely not entirely correct because the radial gradient in the inner solar system is expected to vary on short timescales. However, for our qualitative discussion, this rough assumption is sufficient. Considering now a meteorite that fell in 1970, the 22 Na production rate is determined by the solar modulation function from ∼1965 to ∼1970, which was 〈Φ〉 ∼ 480 MeV. According to Equation ( 18 ), this corresponds to a 22 Na/ 26 Al (1965–1970) production rate ratio of ∼2.08. For a meteorite that fell in 1980, the relevant parameters are 〈Φ〉 ∼ 420 MeV and 22 Na/ 26 Al (1975–1980) ∼2.25. Finally, a meteorite that fell in 1985 experienced 〈Φ〉 ∼ 670 MeV, corresponding to 22 Na/ 26 Al (1980–1985) ∼1.7. Consequently, the variability in 22 Na/ 26 Al production rate ratios for the three cases is more than 30%, sufficient for detailed studies of the temporal variability of the solar modulation function using freshly fallen meteorites. 5.2. Can We Put Constraints on the Meteoroid Orbits? For the qualitative discussion above, we assumed that the meteorites spent their entire lifetime in the same orbit at ∼3 au and