刚刚，发射成功！

Core Points - The Long March 3B rocket successfully launched the Communication Technology Test Satellite No. 21 into its designated orbit on November 21 at 18:55 [2][4] - The satellite is primarily used for satellite communication, broadcasting, television, and data transmission, and will conduct related technology testing and verification [2] - This mission marks the 609th launch of the Long March series of rockets [4]