Comets3 - Comets Halley's Comet was the first to be proven...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Comets Halley's Comet was the first to be proven to be periodic. It was seen in 66Ad, 1066 AD, 1456 AD, 1910 AD and between. Halley chose to study the most recent, to him, and best-tracked comet of 1682. He found evidence of a body with a similar orbit in 1378, 1456, 1531 and 1607 - gaps of 75, 76, 75 and 78 years. Why the differences? It was Halley's triumph to show this could be the effect of gravitational encounters with the giant planets. He predicted its return for the winter of 1758-9. It appeared, on schedule, on Christmas day 1758. Comets are small, ice-rich bodies, a few km in diameter, in eccentric orbits about the Sun. They are distinguished by the detectable tail or tails which extend from them as they approach the Sun. When the tail is weak or arguable, there is an ambiguity between asteroids and comets which provides much discussion. There have been cases of comets "turning into" asteroids as they run out of volatile material after many passes in near the sun....
View Full Document

This note was uploaded on 12/15/2011 for the course AST AST1002 taught by Professor Emilyhoward during the Fall '10 term at Broward College.

Ask a homework question - tutors are online