Asteroids are large pieces of minerals and ice that orbit the sun
between the orbits of Mars and
Jupiter. As you can see from the
pictures, they come in all sorts of
shapes and sizes. Some of them
have craters from where they were struck
by some other piece of matter.
Astronomers even found one that has a
tiny moon orbiting it!
On this page, and in science fiction
movies, the asteroids are very close together. This is not true in space.
The asteroids are far from one another. You could drive your spaceship
through the asteroid belt without worrying about colliding with one.
What are the asteroids? Are they just a
belt of space debris, or are they the remains of a planet?
Bode's Law
 A Strange Coincidence?
A lot of the work in astronomy has been
done by mathematicians, because all the
splendor of the night sky rests in an
invisible web of mathematics. The mathematicians have discovered
many fascinating things about our universe.
One of the
interesting things discovered by mathematicians is the arrangement of spacing of
the planets in our solar system, which is called
Bode's Law, or the TitiusBode Law after the mathematicians
who discovered and published it.
This is how to get the numbers in
Bode's Law:
 A
mathematical formula which
generates, with a fair amount of
accuracy, the semimajor axes of
the planets in order out from the
Sun. Write down the sequence
0,
3, 6, 12, 24, ...
and
add 4 to each term:
4,
7, 10, 16, 28, ...
Then
divide each term by 10. This
leaves you with the series
0.4,
0.7, 1.0, 1.6, 2.8, ...
which
is intended to give you the
semimajor axes of the planets
measured in astronomical units.
Bode's
law had no theoretical
justification when it was first
introduced; it did, however, agree
with the soontobediscovered
planet Uranus' orbit (19.2 au
actual; 19.7 au predicted).
Similarly, it predicted a missing
planet between Mars and Jupiter,
and shortly thereafter the
asteroids were found in very
similar orbits (2.77 au actual for
Ceres; 2.8 au predicted). The
series, however, seems to skip
over Neptune's orbit. The form of
Bode's law (that is, a roughly
geometric series) is not
surprising, considering our
theories on the formation of solar
systems, but its particular
formulation is thought of as
coincidental.
©
1996,1997, 1998, 1999,
2000, 2002, 2003.
Elizabeth
Anne Viau.
All rights reserved.
This material may be
used by individuals
for instructional
purposes but not sold.
Please inform the
author if you use it
at
eviau@earthlink.net
.
