1.   It keeps our main antenna aimed at Earth to within a few thousandths of a degree.

2.   Controllers were baffled when radio signals from the main antenna disappeared, indicating touchdown, then reappeared.

3.   Illustrating how real the problem is, Kessler said astronauts servicing the Hubble Space Telescope found a half-inch hole punched through its main antenna.

4.   Its main antenna is broken.

5.   The transmission rate of the main antenna would have been equivalent to sending the full text of this article in a half-second.