1.   Within our own galaxy there are probably tens of thousands of planetary systems.

2.   And should Mount Wilson researchers discover a planet, or a planetary system still forming, the observatory will quickly recover some of its past prestige.

3.   As in planetary systems, the force depends only on the distance between the electron and the nucleus.

4.   Astronomers are just beginning to discover the wide variety of planetary systems and have yet to figure out just where ours fits in the pattern, Shaw said.

5.   Astronomers say the discovery of newborn planetary systems that resemble our own solar system in its infancy provide images that are like baby pictures.

6.   Astronomers have discovered two more planetary systems in the universe, and they appear to bear little or no resemblance to each other or to the solar system.

7.   Astronomers tracked these perturbations for at least two years before determining that they signaled the presence of the two planetary systems.

8.   Astroare just beginning to discover the wide variety of planetary systems and have yet to figure out just where ours fits in the pattern, Shaw said.

9.   A major discovery announced last week has given birth to a new field of science, the comparative study of planetary systems.

10.   About the only thing that has not astonished astronomers is the discovery itself of another planetary system.