- are minor planets

- is a small rocky or metallic body

travelling through space

- are significantly smaller than

asteroids

- is an icy small Solar System body

that, when passing close to the Sun,

heats up and begins to outgas,

displaying a visible atmosphere or

coma, and sometimes also a tail

- comprises

the Sun and

the objects

that orbit it,

whether they

orbit it

directly or by

orbiting other

objects that

orbit it

directly.

Sun is the star at the

center of the Solar System.

It is almost perfectly

spherical and consists of

hot plasma interwoven with

magnetic fields.

-is the closest planet to the

Sun and the smallest

planet in the Solar System.

-has no natural satellites.

0.4 AU from the Sun

0.055 Earth masses

-has a thick silicate mantle

around an iron core.

-a substantial atmosphere

- It is much drier than Earth

0.7 AU from the Sun

0.815 Earth masses

- is the largest and

densest of the inner

planets.

- the only place where

life is known to exist.

1 AU from the Sun

- It possesses an

atmosphere of mostly

carbon dioxide.

- peppered with vast

volcanoes.

- Its red color comes from

iron oxide (rust) in its soil.

1.5 AU from the Sun

0.107 Earth masses

- are small Solar System bodies composed mainly of refractory rocky and metallic minerals, with some ice.

- occupies the orbit between Mars and Jupiter.

- classified as small Solar System bodies.

Ceres -is the largest asteroid, a protoplanet,

and a dwarf planet.

-was considered a planet when it was

discovered in 1801.

-It was classified as a dwarf planet in

2006.

- It is composed largely of

hydrogen and helium.

- has 67 known satellites.

5.2 AU from the Sun

318 Earth masses

- distinguished by its

extensive ring system

- has 62 confirmed

satellites

9.5 AU from the Sun

95 Earth masses

- is the lightest of the outer

planets

- It has a much colder core

than the other gas giants

and radiates very little heat

into space

- has 27 known satellites

19.2 AU from the Sun

14 Earth masses

- It radiates more internal

heat, but not as much as

Jupiter or Saturn.

- has 14 known satellites

- Neptune is accompanied

in its orbit by several

minor planets, termed

Neptune Trojans.19.2 AU from the Sun

14 Earth masses

- is a great ring of

debris similar to the

asteroid belt, but

consisting mainly of

objects composed

primarily of ice.

- can be roughly

divided into the

"classical" belt and the

resonances.

- A dwarf planet

- in 1930, it was considered

to be the ninth planet; this

changed in 2006 with the

adoption of a formal

definition of planet.

- is the largest known

object in the Kuiper belt.

- is the largest satellite

of the dwarf planet

Pluto.

- may also be referred to

as (134340) Pluto I

Tides are periodic rises and falls of large bodies of water. Tides

are caused by the gravitational interaction between the Earth and the Moon.

The gravitational attraction of the moon causes the oceans to bulge out in

the direction of the moon. Another bulge occurs on the opposite side, since

the Earth is also being pulled toward the moon (and away from the water on

the far side). Since the earth is rotating while this is happening, two tides

occur each day.

Tide changes proceed via the following stages:

• Sea level rises over several hours, covering the

intertidal zone; flood tide.

• The water rises to its highest level, reaching high

tide.

• Sea level falls over several hours, revealing the

intertidal zone; ebb tide.

• The water stops falling, reaching low tide.

Isaac Newton (1642 -1727) was

the first person to

explain tides

scientifically. His

explanation of the

tides (and many

other phenomena)

was published in

1686, in the

second volume of

the Principia.

Spring tides are especially strong tides (they do not have anything

to do with the season Spring). They occur when the Earth, the Sun, and the Moon

are in a line. The gravitational forces of the Moon and the Sun both contribute to

the tides. Spring tides occur during the full moon and the new moon.

Proxigean Spring

Tide is a rare, unusually high

tide. This very high tide occurs

when the moon is both unusually

close to the Earth (at its closest

perigee, called the proxigee) and in

the New Moon phase (when the

Moon is between the Sun and the

Earth). The proxigean spring tide

occurs at most once every 1.5

years.

Neap tides are

especially weak tides. They

occur when the gravitational

forces of the Moon and the

Sun are perpendicular to one

another (with respect to the

Earth). Neap tides occur

during quarter moons.