ANTIPROTONS AT SOLAR MAXIMUM The solar wind is an electron-proton plasma blowing away from the Sun at 400-800 km/sec and can be thought of as a tenuous atmosphere (called the heliosphere) of the Sun extending over most of the solar system. The charged particles in this gust both envelope and are influenced by the Sun's magnetic field. This field, because it rotates with the Sun, gets pretty tangled up (see figure at Physics News Graphics). When new cosmic rays from outside the solar system venture in they are buffeted by wind and field. During the present solar cycle of the 1990s, the configuration of the field is such that positively charged cosmic-ray protons drift into the inner heliosphere via solar polar regions and exit in equatorial regions. After the soon approaching peak period of solar activity (solar maximum), however, the Sun's field will be reversed. Then the negatively charged cosmic-ray antiprotons preferentially follow the polar route and more easily enter the inner heliosphere to be detected by earthbound or satellite detectors. Thus in the period 2001-2010 we should see relatively more antiprotons than in the previous cycle, which is now ending. Physicists at the Bartol Research Institute at the University of Delaware (Thomas Gaisser, gaisser@bartol.udel.edu, 302-831-8113) have calculated when and by how much this antiproton surplus should manifest itself, telling us how well we understand the solar cycle. They have also sought ways of understanding the source of the antiprotons. Most antiprotons are made when commonplace protons strike interstellar dust, but some might have a more spectacular birth in the annihilation of dark matter or in the evaporation of primordial black holes. (Bieber et al., Physical Review Letters, 26 July 1999.)