input: Students' ability to accurately describe the structure and/or evolution of cosmic objects in the universe seen through Chandra. 4A universe (9-12)#2 … Eventually, some stars exploded producing clouds containing heavy elements from which other stars (and presumably planets orbiting them) could later condense. The process of star formation and destruction continues.
output: Standard D: Earth and Space- The Origin and Evolution of the universe- …Billions of galaxies, each of which is a gravitationally bound cluster of billions of stars, now form most of the visible mass in the universe…Stars produce energy from nuclear reactions, primarily the fusion of hydrogen to form helium, These and other processes in stars have led to the formation of all the other elements.