Our Sun is
                                 a star and is
                                 the center of
                               the Solar System.
                               The Solar System
                              consists of the Sun
                              and several planets.
                            Five planets were known
                           to ancient heaven-gazers;
                              now we know eight
                             in addition to Earth.
                                (This does not
                              include the "minor
                           planets," or asteroids.)
                                  In order of
                              increasing distance
                                 from the Sun,
                                the planets are
                            Mercury, Venus, Earth,
                            Mars, Jupiter, Saturn,
                          Uranus, Neptune and Pluto.
                               Pluto is 40 times
                              as far from the Sun
                                 as Earth is.
                             Jupiter, the largest
                                of the planets,
                              is 40 times larger
                            than Earth in diameter.
                                Venus is almost
                            the same size as Earth.
                              When viewed through
                              good binoculars or
                              a small telescope,
                                 Venus at her
                               brightest shows a
                             crescent shape, like
                             that of the crescent
                              phase of the moon.
                               The reddish color
                            of Mars is well known.
                            With a small telescope,
                             it is possible to see
                            details on the surface.
                              Some observers have
                            called these "canals,"
                             and some have guessed
                             that they were built
                            by intelligent beings.
                             Mars, like Earth and
                              some other planets,
                              has moons--two for
                               the planet Mars.
                           Jupiter has colored bands
                               that can be seen
                            with a small telescope,
                           and the famous Red Spot.
                             Jupiter has 11 moons,
                             of which four can be
                           observed with binoculars
                             or a small telescope.
                            The best-known feature
                               of Saturn is its
                            beautiful set of rings.
                            Both Jupiter and Saturn
                           rotate around their axes
                              in about 10 hours--
                                 a short day!
                          Uranus, Neptune and Pluto,
                           the most distant planets,
                              were all discovered
                              after the invention
                               of the telescope.
                              In addition to its
                            great distance from us,
                             Pluto's small size--
                          about one-half the diameter
                                of the earth--
                           makes it beyond the range
                             of small telescopes.
                             The planets have been
                              of intense interest
                               to mankind since
                            earliest times, and now
                           the exploration of space
                          by rocket-launched vehicles
                             promises more answers
                              to more questions.
                                In May of 1989,
                              the month when this
                           was written, the Atlantis
                              spacecraft sent an
                            exploratory vehicle to
                             the farthest reaches
                           of the planetary system.
                            It will be fascinating
                            to see what new wonders
                              will be revealed in
                             the heavens to which
                            man has turned his eyes
                             since earliest times.