Substantial updates have occurred to the Coordinates and Motions and Binary and Variable Star modules.

In the coordinates and motions module this involved the addition of a handful of new questions, grouping questions of a similar topic near each other, and the addition of the daylight simulator (screenshot below). This simulator shows the illumination on Earth as seen from the sun in either a yearly or daily format. We had several questions which involved the yearly format – constructing an animation using the pattern of sunlight every day at noon from a given longitude (usually the prime meridian). We found that students really needed to see the daily format before they could begin to reason with the yearly format.

A number of new questions have been added to the variable and binary star module. Previously most of the questions had focused on concepts related to photometric observations of variable stars. The new questions focus much more strongly on concepts taught in the lecture hall such as center of mass, locations and motions of the stars in a binary system, and light curves.