During the last few months, 17-year-old Debbie Gibson has racked up three straight Top 5 singles, making her one of pop music's most successful new stars and inviting comparisons with such other teen sensations as Tiffany and Lisa Lisa.

Gibson's breakthrough song, of course, is the ballad "Foolish Beat," which moved up from No. 3 to give her her first chart champ after three near- misses with dance-oriented tunes. Her success came at the expense of Rick Astley's second No. 1, "Together Forever," which was knocked down to No. 3 after just one week in the top spot.

Moving up from No. 4 to No. 2 was Michael Jackson's "Dirty Diana," which now has a good shot at giving the "Bad" man yet another chart record: first artist to score five No. 1 singles from one album. But first, Jackson will have to contend with Gibson and "Foolish Beat," which was No. 1 this week in record sales and radio airplay and shows no signs of slowing down.