(meteorobs) Definition of a meteor (was Re: Fifth grade science book)

[Lew Gramer]

Dan, I wasn't able to view the document you attached from your son's science
text book. But some generally accepted definitions related to meteors are:


 'meteor' - a flash of light in the sky, caused by a piece of material entering
earth's atmosphere at high speed (or RE-entering, if it's manmade). A very
bright 'meteor' is also called a 'fireball', and sometimes also a 'bolide'.
Most of the meteors we see in the night sky on a dark moonless night, are
actually caused by cometary debris. Debris from a particular comet can cause
several 'meteors' on a given night, what we call a 'meteor shower'. Other
common names for meteors: "shooting star", "falling star", "wishing star".

 'meteorite' - a piece of solar system material that survives high-speed entry
through earth's atmosphere, to actually reach earth's surface. May survive
whole, or it may reach the surface as fragments; may hit ocean or dry land.
Meteorites (impacts) are much rarer than meteors (flashes of light).

 'meteoroid' - a piece of solar system material, orbiting the sun. May be a
"left-over" from the formation of the solar system, or a piece of debris
sloughed off by a comet (most common), or resulting from impact of solar system
bodies with each other (rare). If it happens to intersect with Earth's orbit
and enter our atmosphere, it will produce a 'meteor'. It may also OCCASIONALLY
produce a 'meteorite' - if it is large enough, dense enough, and slow enough.
Meteoroids range in size from microscopic, to many meters (yards) across. A
really LARGE (>100m), rocky 'meteoroid' is also known as an 'asteroid'. A
really TINY (<1mm or so) particle is called a 'micrometeoroid'.

People who study meteorITES are "meteoriticists". People who study meteorOIDS,
and also meteors and meteor showers, are sometimes called "meteoricists".


Hope this helps your son, Dan! If he (and you) have further interest in
meteors, please check out some of the meteor organizations online, and drop us
an email again some time via one of the addresses on these sites:

  http://www.namnmeteors.org
  http://www.meteorobs.org
  http://www.amsmeteors.org
  http://www.imo.net

Clear skies!

Lew Gramer, NAMN, IMO


--- Dan wrote:
> My son is studying the solar system this week in his science class.  As we
> were going through the chapter, my wife came across the section dealing with
> meteors, meteorites and so forth.  I hope the attachment I send gets to you
> so you can read it, but it give three definitions for a meteor.
> I was always brought up  that a meteor was a piece of rock or debris that was
> burning up entering the earth's atmophere.
> The information comes from our son's fifth grade science book entitled Scott
> Foresman SCIENCE.
> Can you shed some light on which definiton is correct?
> ANd if possible, get back to me as soon as possible, so I can bring this to
> the atttention of the science teacher, while they are on this subject.
> Thanks for your time,
> Sincerely,
> Dan O'Connor
> Tiffin, Ohio

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