rlp writes "Researchers at the Institute for Astronomy in Zurich are reporting that solar sunspot activity is at a 1000-year peak. Records of sunspots have been kept since 1610. The period between 1645 and 1715 (known as the Maunder Minimum) was a period of very few sunspots. Researchers extended the record by measuring isotopes of beryllium (created by cosmic rays) in Greenland ice cores. Based on both observations and ice core records, we are now at a sunspot peak exceeding solar activity for any time in the past thousand years."