The Pierre Auger Observatory has detected more muons from cosmic-ray showers than predicted by the most up-to-date particle-physics models. This finding suggests that the best models of hadronic interactions are missing something. Read more about Pierre Auger Observatory and proposed missing links here on the APS Physics website.
Teresa Wilson’s monthly series “This Month in Astronomical History” has released its November publication “Launch of Sputnik 2”. Each month, as part of this new series from the Historical Astronomy Division of the AAS, an important discovery or memorable event in the history of astronomy will be highlighted. This month, we look as the Soviet Union’s launch of Sputnik 2. You can read the compete article here or on aas.org.