 |
| Facts About the Solar
System |
| The 10 Largest Bodies
in the Solar System |
| The 10 Largest
Planetary Moons |
 Mercury
is the smallest planet in the Solar System.
Despite being so close to the Sun, it is believed
that water ice may actually be present in the
protected shadows of some craters. |
 Venus
is the sixth largest planet. Except for the Sun
and the Moon, it is the brightest object in the
sky. Its rotation is unusual in that it is both
very slow and retrograde. Venus is similar enough
to Earth in many ways that the two have often
been called "sister planets." The first
spacecraft to land on another planet was the
Soviet Union's Venera 7, which landed on
Venus in 1970. |
 Mars
is the seventh largest planet. At its closest
approach to Earth it is the third brightest
object in the night sky. The largest mountain in
the Solar System is on Mars. It is one of only
two planets in the Solar System to have had a
spacecraft land on its surface. |
 Asteroids
are the relatively small rocky bodies that occupy
the orbital path between Mars and Jupiter. Once
thought to be the remnants of a former planet, it
is now more commonly believed that they occupy a
place where a sizable planet could have formed,
but was prevented from doing so. They range in
size from about 480 miles in diameter, down to
just a few feet across. |
 Jupiter
is the largest planet in the Solar System. In
fact, it is so big that all eight of the other
planets (including Pluto) could fit within it and
still have room to spare. The Great Red Spot for
which it is best known has been seen from Earth
for more than 300 years. As of 2004, Jupiter has
63 known satellites, two of which would be
considered planets if they orbited the Sun. |
 Saturn
is the second largest planet. Although they look
continuous from Earth, Saturn's rings are
actually composed of innumerable small particles,
each in an independent orbit. To date, 34
Saturnian moons have been named. |
 Rhea
is the fourteenth of Saturn's known satellites,
and its second largest. |
 Titan
is the fifteenth of Saturn's moons, and its
largest. Unlike almost every other satellite in
the Solar System, it has a significant
atmosphere. Pictures of its surface indicate that
is clouds may actually produce enough
"rain" to create rivers and lakes. |
 Uranus
is the third largest planet. Discovered by
William Herschel in 1781, it was the first planet
to be discovered in modern times. It did not,
however, receive its current name until 1850. |
 Oberon
is the second largest satellite of Uranus. |
 Titania
is the fourteenth and largest of Uranus' known
satellites. |
 Triton
is the largest moon of Neptune. It is the only
large satellite in the Solar System to circle a
planet in a direction opposite to the rotation of
the planet. |
 Pluto
is not only the smallest planet in the Solar
System, it is actually smaller in diameter than
seven of the system's moons. On August 24, 2006,
the International Astronomical Union reclassified
Pluto as a "dwarf planet." |
