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Abstract—‐We demonstrate the presence of solar flare as well as neutron capture effects in the isotopic composition of rare gases in the Fermo regolith breccia acquired on its parent body based on the measurements of tracks, rare gases and radionuclides. The track density along a 3.2 cm long core decreases by a factor of about 6 and by more than a factor of 13 within the meteorite, indicating small (2–9 cm) and asymmetrical ablation. Rare gases show a large trapped component; the isotopic ratios, particularly 20Ne/22Ne ≃ 11 and 20Ne/36Ar = 10 are indicative of a solar component. The galactic cosmic‐ray exposure age is determined to be 8.8 Ma. Activities of a dozen radionuclides ranging in half‐life from 16 day 48V to 0.73 Ma 26Al are consistent with their expected production rates. Track, rare gas and radionuclide data show that the meteoroid was a small body (≤ 120 kg) and had a simple, one‐stage exposure history to cosmic rays in the interplanetary space. However, 82Kr and 128Xe show an excess due to neutron irradiation on the parent body of the meteorite. The presence of solar gases and the neutron capture effects indicate several stages of irradiation on the parent asteroid. The chemical composition of Fermo confirms that it belongs to the H group of ordinary chondrites with lithic clasts having varying compositions. δ15N is found to be 8.3 ± 1.2%0, close to the typical values observed in H chondrites.

Abstract—Measurements of particle tracks, cosmogenic radionuclides, and rare gas isotopes in Mbale indicate that the meteoroid had a simple, one‐stage exposure for 30.2 Ma in interplanetary space. On the basis of the measured track production rates and 60Co and 26Al activities, the meteoroid is estimated to be a sphere with a radius of ∼36 cm. The activities of several cosmogenic radionuclides (i.e., 57Co, 54Mn, 22Na, 44Ti, and 26Al) in two fragments having different shielding, as estimated by their track density and 60Co activity, provide the depth variation in their production rates. Cobalt‐57, 54Mn and 22Na activities agree with the production that is expected around the maximum of the solar cycle 22 as calculated from the Sunspot numbers. The U, Th‐4He and K‐40Ar ages are measured to be 0.54 Ga indicating a late thermal event which is in agreement with the thermal history of some other L group chondrites. The trapped N has δ15N of −57 ± 4%o, which is much lighter than the average L‐group chondrite value; this indicates the presence of an isotopically anomalous light N component.

In this paper we present the δ18O profile of Globigerinoides ruber measured in the GT90/3 shallow water Ionian sea core, dated with high precision. The δ18O profile covers the period 1200–1900 AD, with a resolution of 3.87 years. This long record of 700 years of δ18O allows us to identify the imprint of the solar cycle in a climatic record. In fact, the spectral analysis of the time series performed with different methods shows a dominant periodicity of about 11 years with an amplitude of ≈0.07‰. The signal is in opposition to the sunspot number cycle. This component is identified at a high significance level by Monte Carlo Singular Spectrum Analysis (MC-SSA).

We confirm and extend the results previously reported on the carbonate profile of the GT14 Ionian Sea core [Cini Castagnoli et al., 1990]. A second, much longer core (2.81 meters), named GT89/3, has been taken about 1 km apart from the previous one. The carbonate profiles of the two cores are impressively similar; the details of the CaCO3variations in the two sediments match on the scale of the sampling interval Δd = 2.5 mm used for both cores. We show that Δd corresponds to the mud deposited in a time interval Δt = 3.87±0.04 years, a value which is constant throughout the entire length of the cores. This precision is achieved by the tephroanalysis of the two cores. In this approach the markers of well‐known historical eruptions in the Vesuvius area are recognized (Pompei, AD 79, Pollena, AD 472, Ischia, AD 1301), providing a precise dating which accurately tunes that obtained by the radiometric method. The correlation between the carbonate profile of the GT14 core and the tree‐ring radiocarbon record has been discussed in [Cini Castagnoli et al., 1990]; here we extend these results and show that the same correlation holds at least up to 1690 BC. Due to the longer length of the GT89/3 time series, we also show that three periodic components at about 206 yr, 228 yr and 179 yr may now be resolved in the carbonate series, in close agreement with the results already found for the radiocarbon record.

During the year 1969 two long-lived centres were active on the Sun at Carrington longitudes 50° < L < 100° and 250° < L < 300°. About 80% of the flares of importance ? 1B, produced during this period, originated in these zones.

We have correlated intensity decreases in the galactic component of cosmic rays observed at the Earth with solar phenomena. We have found that there exist intensity decreases detected underground, which are probably associated with long-lived interplanetary streams and which are not directly associated with single flares. We expect to detect the streams with underground monitors before the arrival of the streams at the Earth. The early detection will be in the northern or in the southern hemisphere, depending on the sign of the interplanetary field.