Asked in Planetary ScienceComets
When was halleys comet discovered?
July 01, 2010 11:09PM
The first "certain" appearance of Halley's Comet is from 240 BC, in the Chinese chronicle Records of the Grand Historian or Shiji, which describes a comet that appeared "in the east and moved north".
Asked in Comets
How many times did halleys comet appear in the 20th century1901-2000?