Transcript Saturn is the only planet in our Solar System less den

THE UNIVERSE
In beginning there was nothing
no galaxies
no stars
no planets
There was no matter at all, not even tiny particles
existed.
So how was something
as huge and complex
as the Universe
created out of nothing?
The Big Bang theory tells us how the Universe
began and how it is evolving.
According to it, at one stage the Universe must
have come from a single point
Astronomers are now fairly sure that it happened 15 billion years ago.
Just one second after the
birth of the Universe space was flooded with particles.
Over the next 300 million
years stars and galaxies
began to evolve into the
kind of cosmic landscape
that we recognise today.
Our solar system is
just a tiny part of the
universe
There are eight planets
in our solar system
Mercury is the smallest and fastest moving
planet in our Solar System.
It has no seasons.
The planet has a huge range in temperatures. Its surface
ranges from -270°F to 800°F (-168°C to 427°C), and it
means about 600°C.
It is also the closest planet to our Sun. If you were on the
surface of Mercury, the Sun would look almost 3 times
as big as it does from Earth!
Venus is the second planet from the sun in
our solar system and the hottest one.
Venus is also known as the "morning star"
or the "evening star".
Venus rotates in the opposite direction of the other planets and no one knows why it has this unusual rotation.
Venus is almost as big as planet Earth but it rotates
very slowly. As a conequence, each day on Venus takes
243 Earth days.
The Earth is the third planet from the Sun
in our Solar System.
It is the only planet in our Solar System that
is known to support life.
The temperature on Earth ranges from between -127°F to
136°F (-88°C to 58°C; 185 K to 311 K).
The Earth revolves around the Sun at a speed of about 30
km/sec, but its rotation is slowing down very slightly over
time, about one second every 10 years.
Mars is the fourth planet from the Sun in
our Solar System.
The surface of Mars is dry and rocky, and it
has 2 tiny moons.
Mars is much colder than the Earth. Mars' surface temperature averages -81 °F (-63 °C). The ground is frozen and ,
occasionally, there are clouds in its atmosphere.
Recent photos from Mars indicate that there might be some liquid water near the surface.
Jupiter is the fifth and largest
planet in our Solar System.
Jupiter is made up of gases
and liquids the gravity on it is
254% of the gravity on Earth .
Jupiter has no seasons. A day in Jupiter takes 9.8 Earth
hours and a year, 11.86 Earth years.
Jupiter has four large moons and dozen of small ones.
It also has faint, dark rings.
Jupiter is the 6th planet from
the Sun in our Solar System.
Saturn is made mostly of hydrogen and helium gas and
it has lots of rings.
Each day on Saturn takes 10.2 Earth hours. A year on
Saturn takes 29.46 Earth years
Saturn is the only planet in our Solar System less dense than water. It could float in water!
Uranus is the 7th planet from
the Sun in our Solar System.
It is a blue icy planet covered
with clouds and encircled by
a belt of rings and moons.
Uranus is a very bright planet that can be seen with the
naked eye under dark sky conditions. It can be easily
found with binoculars
A space craft could never land on Uranus because the
surface is made of gas and is not solid.
Neptune is the 8th planet from
the Sun in our Solar System.
It is a giant, frigid planet with
strong winds.
Neptune cannot be seen using the eyes alone. Neptune
was the first planet whose existence was predicted mathematically
Since Neptune was discovered in 1846, it has not yet
completed a single revolution around the sun .
All these planets
evolve around the
Sun.
Rival scientific theories try to predict
whether the universe will be of finite
or infinite duration.
According to the Big Bang theory, in
the future the Universe will recollapse.
Other theories say that that the expansion of the universe seems to be
accelerating and will accelerate for
eternity.
What do you you think about it ?