Which one of the following best expresses the main idea of the passage? A. The observation of Herculina represented the crucial event that astronomical observers and theoreticians had been waiting for to establish a convincing case for the stability of asteroid-satellite systems. B. Although astronomers long believed that observation supports the existence of stable asteroid-satellite systems, numerous recent reports have increased skepticism on this issue in astronomy. C. Theoreticians' views on the stability of asteroid-satellite systems may be revised in the light of reports like those about Herculina. D. Astronomers continue to consider it respectable to doubt the stability of asteroid-satellite systems, but new theoretical developments may change their views. E. The Herculina event suggests that theoreticians' views about asteroid-satellite systems may be correct, and astronomers agree about the kind of evidence needed to clearly resolve the issue.