1.   And it helped push many radio broadcasters like Clear Channel Communications, the dominant terrestrial radio company, to halt Internet broadcasting altogether.

2.   But there are trends that could challenge terrestrial radio to hold on to that lead.

3.   Cohen scorns proposals to build future radio observatories on the far side of the Moon to escape terrestrial radio interference.

4.   Holders of terrestrial radio licenses make no secret of their wish to hold satellite broadcasting at bay.

5.   More to the point, perhaps, satellite-based radio is unlikely to be a serious competitor for terrestrial radio in the foreseeable future.

6.   Neither service will carry signals from existing terrestrial radio stations, so both will be trying to create new markets.

7.   Terrestrial radio broadcasters are bracing for a new kind of competitor.

8.   Terrestrial radio stations may have to start their own multichannel formats.