Issues

The following summary of present knowledge and speculation concerning properties of the interplanetary medium gives a brief account of some theoretical ideas advanced in the past twenty years and reviews some experimental observations which have been made from the earth. Particular attention is given to direct measurements of plasma properties carried out by means of the Explorer X satellite.

Under the AAPT‐AIP Regional Counselor Program in Physics, the individual counselors are faced with the problem of helping to encourage better high‐school physics teaching in their own localities. Here, the regional counselor for the state of New York reports on one stimulating approach to that problem carried out with the cooperation of school authorities and the state section of the American Physical Society.