Halley's Comet
Facts About Halley's Comet:
- This is a "periodic" comet that returns to our part of the Solar System and is visible from Earth every 76 years.
- The first recorded observation of this comet was in 240 BC and sightings have been recorded for every return since. However, people thought it was a different comet each time - it wasn't recognized as the same comet for nearly a thousand years.
- In 1705 using historical records, Edmond Halley calculated that multiple previous comet sightings were actually the same one. He correctly predicted the next return, but sadly he died before actually seeing it.
- Edmond Halley spelt his name many different ways and the exact pronunciation is unclear. Either "Halley" or "Haley" is acceptable.
- This is the only naked-eye comet that can appear twice in a human lifetime.
- In 1986 it became the first comet to be closely examined by a spacecraft (the Giotto robotic space probe).
Classification: Comet (orbiting Sun)
Names: Halley's Comet, 1P/Halley
Naming: Astronomer Edmond HalleyOrbital Period: 75.3000
Eccentricity: 0.96700000