The document provides an overview of the key components of our solar system, including the sun, planets, moons, asteroids, comets, and other celestial bodies. It describes each planet from Mercury to Neptune, as well as other objects like stars, meteoroids, and constellations. The moon is also summarized as Earth's natural satellite that orbits our planet. The document aims to educate about the makeup and contents of our solar system through detailed yet concise explanations of its most important parts.
4. Introduction
• The solar System is made up of all the
planets that orbit our Sun. In addition to
planets, the solar System also consists of
moons, comets, asteroids, minor planets,
dust and gas. The inner solar system
contains the Sun, Mercury, Venus, Earth and
Mars. The main asteroid belt lies between
the orbits of Mars and Jupiter. The planets of
the outer solar system are Jupiter, Saturn,
Uranus and Neptune (Pluto is now classified
as a dwarf planet).
5. Sun
• The sun is the largest object in the solar
system. It is a middle-sized star and there are
many other stars out in the universe just like it.
Even though it is only a middle-sized star it is
large enough to hold over 1 million Earth’s
inside if it were hollow. The temperature on
the sun is far too much for any living thing to
bear. On the surface it is 10,000 degrees
Fahrenheit and the core is a stunning
27,000,000 degrees Fahrenheit.
6. Mercury
• Mercury is the smallest and
innermost planet in the solar System. Its
orbit around the Sun takes 87.97 days,
the shortest of all the planets in the
solar System. It is named after the
Roman deity Mercury, the messenger of
the gods.
7. Venus
• Venus is the second planet from the Sun.
It is named after the Roman goddess of
love and beauty. As the second-brightest
natural object in the night sky after
the Moon, Venus can cast shadows and,
rarely, is visible to the naked eye in broad
daylight.
8. Earth
• Earth is the third planet from the Sun and the
only astronomical object known to harbor life.
According to radiometric dating and other
evidence, Earth formed over 4.5 billion years
ago. Earth's gravity interacts with other objects in
space, especially the Sun and the Moon, which is
Earth's only natural satellite. Earth orbits around
the Sun in 365.256 solar days, a period known as
an Earth sidereal year. During this time,
Earth rotates about its axis 366.256 times, that is, a
sidereal year has 366.256 sidereal days.
9. Mars
• Mars is the fourth planet from the Sun and the
second-smallest planet in the solar
System after Mercury. In English, Mars carries the
name of the Roman god of war and is often
referred to as the 'Red Planet'.[16][17] The latter
refers to the effect of the iron oxide prevalent on
Mars' surface, which gives it a reddish
appearance distinctive among the astronomical
bodies visible to the naked eye.[18] Mars is
a terrestrial planet with a thin atmosphere, with
surface features reminiscent of the impact
craters of the Moon and the valleys, deserts
and polar ice caps of Earth.
10. Jupiter
• Jupiter is the fifth planet from the Sun and
the largest in the solar System. It is a gas giant with
a mass one-thousandth that of the Sun, but two-
and-a-half times that of all the other planets in the
solar System combined. Jupiter is one of the
brightest objects visible to the naked eye in the night
sky, and has been known to ancient civilizations
since before recorded history. It is named after
the Roman god Jupiter.[18] When viewed from Earth,
Jupiter can be bright enough for its reflected light to
cast shadows,[19] and is on average the third-
brightest natural object in the night sky after
the Moon and Venus.
11. Saturn
• Saturn is the sixth planet from the Sun and the
second-largest in the solar System,
after Jupiter. It is a gas giant with an average
radius of about nine times that of Earth.[18][19] It
only has one-eighth the average density of
Earth; however, with its larger volume, Saturn
is over 95 times more massive.[20][21][22] Saturn
is named after the Roman god of wealth and
agriculture; its astronomical symbol (♄)
represents the god's sickle.
12. Uranus
• Uranus is the seventh planet from the Sun. It has the
third-largest planetary radius and fourth-largest
planetary mass in the solar System. Uranus is similar in
composition to Neptune, and both have bulk chemical
compositions which differ from that of the larger gas
giants Jupiter and Saturn. For this reason, scientists often
classify Uranus and Neptune as "ice giants" to distinguish
them from the gas giants. Uranus' atmosphere is similar to
Jupiter's and Saturn's in its primary composition
of hydrogen and helium, but it contains more "ices" such
as water, ammonia, and methane, along with traces of
other hydrocarbons. It has the coldest planetary
atmosphere in the solar System, with a minimum
temperature of 49 K (−224 °C; −371 °F), and has a
complex, layered cloud structure with water thought to
make up the lowest clouds and methane the uppermost
layer of clouds. The interior of Uranus is mainly
composed of ices and rock.[
13. Neptune
• Neptune is the eighth and farthest known planet from
the Sun in the solar System. In the solar System, it is the
fourth-largest planet by diameter, the third-most-
massive planet, and the densest giant planet. Neptune
is 17 times the mass of Earth, slightly more massive
than its near-twin Uranus. Neptune is denser and
physically smaller than Uranus because its greater
mass causes more gravitational compression of its
atmosphere. Neptune orbits the Sun once every
164.8 years at an average distance of
30.1 AU (4.5 billion km; 2.8 billion mi). It is named
after the Roman god of the sea and has
the astronomical symbol ♆, a stylized version of the
god Neptune's trident.
15. Stars
• A star is an astronomical object consisting of a
luminous spheroid of plasma held together by its
own gravity. The nearest star to Earth is the Sun.
Many other stars are visible to the naked eye
from Earth during the night, appearing as a
multitude of fixed luminous points in the sky
due to their immense distance from Earth.
Historically, the most prominent stars were
grouped into constellations and asterisms, the
brightest of which gained proper names.
Astronomers have assembled star catalogues that
identify the known stars and provide
standardized stellar designations. The observable
Universe contains an estimated 1×1024 stars , but
most are invisible to the naked eye from Earth,
including all stars outside our galaxy, the Milky
Way.
16. Comets
• A comet is an icy, small solar System body that, when passing close to the Sun, warms
and begins to release gases, a process called outgassing. This produces a visible
atmosphere or coma, and sometimes also a tail. These phenomena are due to the
effects of solar radiation and the solar wind acting upon the nucleus of the
comet. Comet nuclei range from a few hundred meters to tens of kilometers across
and are composed of loose collections of ice, dust, and small rocky particles. The
coma may be up to 15 times Earth's diameter, while the tail may stretch
one astronomical unit. If sufficiently bright, a comet may be seen from Earth without
the aid of a telescope and may subtend an arc of 30° (60 Moons) across the sky.
Comets have been observed and recorded since ancient times by many cultures.
17. Asteroids
• Asteroids are minor planets, especially of
the inner solar System. Larger asteroids have also
been called planetoids. These terms have
historically been applied to any astronomical
object orbiting the Sun that did not resolve into a
disc in a telescope and was not observed to have
characteristics of an active comet such as a tail.
As minor planets in the outer solar System were
discovered that were found to have volatile-rich
surfaces similar to comets, these came to be
distinguished from the objects found in the
main asteroid belt.[1] In this article, the term
"asteroid" refers to the minor planets of the inner
solar System, including those co-orbital
with Jupiter.
18. Meteoroids
• A meteoroid is a small rocky or metallic
body in outer space. Meteoroids are
significantly smaller than asteroids, and
range in size from small grains to one-
meter-wide objects. Objects smaller than
this are classified
as micrometeoroids or space dust. Most are
fragments from comets or asteroids,
whereas others are collision
impact debris ejected from bodies such as
the Moon or Mars.
19. Constellation
• A constellation is a group of stars that appears
to form a pattern or picture like Orion the
Great Hunter, Leo the Lion, or Taurus the
Bull. Constellations are easily recognizable
patterns that help people orient themselves
using the night sky. There are 88
“official” constellations.
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24. Moon
• The Moon is an astronomical
body orbiting Earth as its only natural
satellite. It is the fifth-largest satellite in
the solar System, and by far the largest
among planetary satellites relative to the
size of the planet that it orbits (its primary).
The Moon is, after Jupiter's satellite Io, the
second-densest satellite in the solar System
among those whose densities are known.