Comets are small, fragile, irregularly shaped bodies composed of a mixture of non-volatile grains and frozen gases. They have highly elliptical orbits that bring them very close to the Sun and swing them deeply into space. ... For this reason, comets are said to be short-lived, on a cosmological time scale.
www.solarviews.com/eng/comet.htm www.solarviews.com/eng/comet.htm
Unlike the other small bodies in the solar system, comets have been known since antiquity. There are Chinese records of Comet Halley going back to at least 240 BC. The famous Bayeux Tapestry, which commemorates the Norman Conquest of England in 1066, depicts an apparition of Comet Halley.
www.nineplanets.org/comets.html www.nineplanets.org/comets.html
Astronomers classify comets according to how long they take to orbit the sun. Short-period comets need less than 200 years to complete one orbit, while long-period comets take 200 years or longer.
www.nasa.gov/worldbook/comet_worldbook.html www.nasa.gov/worldbook/comet_worldbook.html
Missions to Asteroids ... Current and Past Missions ... Asteroid Fact Sheet...
nssdc.gsfc.nasa.gov/planetary/planets/asteroidpage.html
Information on Selected Comets ... The image shown is a view of the nucleus of Comet Halley taken by the Giotto spacecraft. Below is a table of information on selected comets, and at the bottom of the page are comments on the comets.
nssdc.gsfc.nasa.gov/planetary/factsheet/cometfact.html nssdc.gsfc.nasa.gov/planetary/factsheet/cometfact.html
Comet - Wikipedia, the free encyclopedia
Source
A comet is a Small Solar System Body that orbits the Sun. When close enough to the Sun, a comet exhibits a visible coma (fuzzy "atmosphere"), and sometimes a tail, both because of the effects of sol...
en.wikipedia.org/wiki/Comet
General information and data, pictures, details on the most interesting one ... Not long ago, many people thought that comets were a sign that something bad was about to happen to them. People didn't understand how objects in the sky moved, so the sight of a comet must have been very disturbing.
www.windows.ucar.edu/tour/link=/comets/comets.html www.windows.ucar.edu/tour/link=/comets/comets.html
Not long ago, many people thought that comets were a portent that something bad was about to happen to them. Since people did not yet understand about the objects in the solar system and how they moved, the sight of a comet must have been very disturbing.
www.windows.ucar.edu/tour/link=/comets/comets.html&edu=... www.windows.ucar.edu/tour/link=/comets/comets.html&edu=high
Small Comets - A New Class of Interplanetary Bodies Confirmed ... Every few seconds a "snowball" the size of a small house breaks up as it approaches Earth and deposits a large cloud of water vapor in Earth's upper atmosphere. ... How to Search for Small Comets...
smallcomets.physics.uiowa.edu/ smallcomets.physics.uiowa.edu/
Q&A
7,722 questions about
Comets