Download Powerpoint Notes on Meteors, Asteroids and Comets

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Meteoroid – a chunk of rock or dust in space.
(these come from comets or asteroids)
Meteor – a chunk of rock or dust that enters
our atomosphere and burns up, producing a
streak of light time lapse photo of meteor shower
Meteorite – a meteor so large it does not
completely burn up and strikes the surface.
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Rocky objects, most of which revolve around
the sun in fairly circular orbits between the
orbits of Mars and Jupiter.
There are more than 100,000 asteroids
Most are small, but some are so large we have
named them. Ceres, for example, is over 300
km across.
We keep track of the biggest ones because they
can get nudged out of orbit and could collide
with Earth. (ie. End of dinosaurs 65 mya)
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Comets are a loose collection of ice, dust and small
rocky particles.
Comet orbits are usually highly elliptical
As it nears the sun, solar energy heats up the
comet and released gas and dust form a fuzzy
outer layer called the coma. (the nucleus is the solid inner core)
Comet means, “long haired star” in Greek. This
refers to the tail which, due to solar radiation,
always points away from the sun. These tails can
be 100 million km long or almost the entire
distance from the Earth to the Sun.
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Comets can come from the Kuiper Belt or the
Oort cloud.
They may have periodic orbits, like Halley’s
comet that comes around every 76 years or,
they may be disturbed by gravitational waves
that send them into the inner solar system.
They may collide with a planet, the sun, or
swing around the sun and never return.
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The ESA landed a probe on a comet in 2014
More information about the Rosetta mission
Actual pictures from the mission
What happened to Philae?