11.   The Cambridge astronomers Thursday had called an impact unlikely but possible.

12.   The object travels in what astronomers call a horseshoe pattern that spirals forward along the solar orbital path of Earth.

13.   Two other novae, as astronomers call the phenomenon, will be observed during the shuttle mission.

14.   While some astronomers called it reasonable, others, including Dr. Donald K. Yeomans of the Jet Propulsion Laboratory in Pasadena, Calif., deemed the idea an outrage.

15.   Thousands of Nevada residents enjoyed what astronomers called the best display of the northern lights over the state in at least two decades.