How to Make a Rainbow/Spectrum
The classical way to make a spectrum - ala
Isaac Newton - is to stick an optical prism into sunlight and twist it about until you get your rainbow. However, you might be disappointed the first time you try this, especially if you're thinking of the cover art of Pink Floyd's 'Dark Side of the Moon'! Here are some tips for you.
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Telescope Basics
There's a couple of major differences between telescopes designed for terrestrial and
astronomical viewing. The first concerns how they are mounted on their tripod.
'Regular' (i.e. terrestrial) telescopes can be swivelled horizontally, or vertically -
just like a camera on a tripod. This is called an altazimuth mount, or AZ for short.
But astronomical telescopes generally use what is called an equatorial mount, or EQ,
which has the vertical axis tilted over 23.5 degrees so its parallel with the Earth's axis
of rotation. This makes it easier to track stars as they move across the sky,
and you can find an object of interest by setting its coordinates (RA & Dec) on the axes'
scales.
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The Solar System
The solar system consists of the Sun; the eight planets,
168 satellites of the planets,
a large number of small bodies (the comets and asteroids),
and the interplanetary medium.
A planet is any of the eight major celestial bodies
(Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune) that orbit the sun and shine by reflecting its light.
Smaller bodies that also have the sun as their primary (that is,
are not satellites of a planet) are called asteroids or planetoids.
The inner solar system contains the Sun, Mercury, Venus,
Earth and Mars;
The planets of the outer solar system are Jupiter, Saturn, Uranus,
and
Neptune.
The orbits of the planets are ellipses with the Sun at one focus,
though all except Mercury are very nearly circular.
The orbits of the planets are all more or less in the same plane
(called the ecliptic and defined by the plane of the Earth's orbit).
The ecliptic is inclined only 7 degrees from the plane of the Sun's
equator.
They all orbit in the same direction
(counter-clockwise looking down from above the Sun's north pole);
all but Venus, Uranus and Pluto also rotate in that same sense.
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Computer
Generally, a computer is any electronic data-processing device that performs tasks,
such as mathematical calculations or electronic communication, under the control of
a set of instructions called a program.
Programs usually reside within the computer's main memory and are retrieved and
processed by the computer's electronics, and the program results are stored or
routed to output devices, such as video display monitors or printers.
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Scientific Method
Science is the objective pursuit of reliable knowledge.
Although one might "know" something through authority, faith, or intuition,
scientific method is distinct in that it must be possible for other
investigators to ascertain the truth of scientific theories.
Its founded on objective observation,
the formulation of hypotheses that fit the data and predict other posibilities,
repeatable experiments that can fail as well as succeed,
and analysis and review by the scientific community.
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Mathematics
Mathematics is the study of numbers, sets of points, and various
abstract elements, together with relations between them
and operations performed on them.
Originally mathematics was concerned with the properties of numbers and
space, as the science of quantity, whether of magnitudes, as in geometry,
or of numbers, as in arithmetic, or the generalization of these two fields,
as in algebra.
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