Transcription: Halley's Comet is certainly the most famous of all comets. It has been observed at every return by people all over the world since 164 B.C. Halley's Comet was first sighted by ancient Chinese astronomers in 1059 B.C. However, it was not until centuries later that astronomers realized that Comet Halley was in a circular orbit and returned at regular intervals. polls.
(.mp3)