Transcript It all began with a Big Bang!

It all began with a Big Bang!
about 14 billion years ago
The Big Bang
The Universe began in a Big Bang about 14 billion years ago.
At that time, the entire Universe was inside a bubble that
was thousands of times smaller than a pinhead. It was
hotter and denser than anything we can imagine.
Then it suddenly exploded. The Universe that we know was
born.
In a fraction of a second, the Universe grew from smaller
than a single atom to bigger than a galaxy. It is still
expanding today.
The Big Bang
This is an
impression of
the early years
of our Milky
Way galaxy,
about 12.7
thousand
million years
ago.
A Nebula
• An exploded bucket
of paint? No. It‘s a
picture of the Swan
Nebula, a collection
new born stars. They
are surrounded by
colorful blankets of
glowing gas and an
enormous cold, dark
hydrogen cloud.
The area of the
nebula shown in this
picture is 3500 times
bigger than our Solar
System.
What is space?
In space, no one can
hear you scream. This
is because there is no
air in space – it is a
vacuum. Sound waves
cannot travel through a
vacuum.
'Outer space' begins
about 200 km above
the Earth. Space
appears as a black
blanket dotted with
stars.
Space is not empty, the
openings between the
stars and planets are
filled with huge
amounts of gas and
dust.
The birth of galaxies
•
•
We don’t know anything that happened during the first 300 000 years of the Universe.
Millions of years passed, and the dense areas attracted material because they had more gravity.
•
Finally, about 100 million years after the Big Bang, the gas became hot and dense enough for the
first stars to form. New stars were being born 10 times as fast as now.
•
Large collections of stars soon became the first galaxies.
•
Telescopes now begin to find galaxies that were created about one billion years after the Big Bang.
These small galaxies are much closer together than galaxies are today.
•
Like two flames moving towards each other, galaxies combine into bigger galaxies.
•
Our Milky Way galaxy came together in this way.
Extreme life
Building stones of
life
• Today, scientists
are not so sure
that life began on
or near the
Earth's surface.
• Everywhere we
look, there seems
to be life – even
several kilometres
underground. It
may be that life
began at the
bottom of the
oceans, where
hot springs
provided energy
instead of
sunlight.
Galaxies
Nearly all stars belong to
gigantic groups known as
galaxies.
The Sun is one of at least
100 billion stars in our
galaxy, the Milky Way.
And there are billions of
galaxies in the Universe.
Everywhere we look in
the sky there are galaxies
of different shapes and
sizes.
A Spiral galaxy
Galaxies were born only a
few hundred million
years after the Universe
was created.
This is a
view of a
collision
(bumping
into
eachother)
between
two spiral
galaxies,
called the
Antennae
Galaxies
Star birth
New stars are born in this galaxy, Galaxy NGC
1569
• After their
birth, most
young stars lie
at the centre of
a flat disc of
gas and dust.
Most of this
material is
eventually
blown away by
the star’s
radiation.
Before this
happens,
planets may
form around
the central star.
Star birth
• The bright dots
are new born
stars, comparable
in mass to the Sun.
• The bright object,
above and slightly
to the right of
centre, is a new
massive star, much
heavier than the
Sun
Star death
a dying star called NGC 6369
• Most stars take
millions of years to
die.
• Stars heavier than
eight times the mass
of the Sun end their
lives very suddenly.
• They try to keep
alive by burning
different fuels, but
this only works for a
few million years.
Then they blow
themselves apart in
a huge explosion.
• The Sun is a star. Like most
stars, the Sun is a ball of very
hot gas that gives off huge
amounts of light, heat and
other radiation.
• There are many different
types of star. Red stars are
the coolest. Blue-white stars
are the hottest. Yellow stars
like the Sun are in-between
•
• Stars come in many sizes. The
Sun is medium-sized.Some
stars are much bigger and
hotter than the Sun.
The Milky Way
A view of our
Milky Way galaxy.
In the galaxy you
can see a black
hole,called,GRO
J1655-40.
The yellow star is
our Sun.
We live in a large spiral galaxy called the Milky Way.
The Sun and its planets (including Earth) lie in this quiet part of the galaxy, about half way
out from the centre.
The Milky Way rotates once every 200 million years. It is made up of at least 100 billion
stars, as well as dust and gas. It is so big that light takes 100 000 years to cross from one
side to the other.
Asteroids – the minor planets
This is a picture of
an asteroid and its
moon
Asteroids are small
bodies made of rock
that have been left
over from the
formation of the
planets 4.5 billion
years ago.
They are often known
as 'minor planets'.
There are billions of
these asteroids.
Asteroid families
Some asteroids are stony,
some are made of metals,
such as iron and nickel.
Most are black-brown in
colour and rich in carbon.
Many asteroids belong to
families.
Each family has the same
colour and seems to be
made of the same
materials.
This shows how
families of
asteroids circle
around
Meteorites
A Meteor Crater in the USA. The crater was
made 49 000 years ago when a 10 000 000
tonne meteor fell on earth
• Every day about 50
tonnes of rocky
material from
space lands on the
Earth's surface.
These rocks are
called meteorites.
• Nearly all
meteorites come
from the main
asteroid belt
between Jupiter
and Mars.
• Sometimes an
entire asteroid can
break apart.
• Many thousands of
meteorites have
been found on
Earth.
Meteorites
• This is a
meteorite
from
Mars.
• Some
scientists
believe it
contains
evidence
that there
is life on
Mars.
The Sun is our nearest star. The Sun
provides us with light and heat.
The Sun
It also gives out dangerous ultraviolet
light which causes sunburn and may
cause cancer.
Without the Sun there would be no
daylight, and our planet would be a
dark, frozen world, with no oceans of
liquid water and no life.
This big ball of hot gas is 1.4 million
km in diameter across, so 109 time
the earth diameter. It has a mass of
2 million-trillion-trillion-trillion
kilograms, it weighs as much as 330
000 Earths. About 1 300 000 Earths
would fit inside the Sun.
Our nearest star
This is a temperature map of
the Sun.
In the image bright indicates
hotter plasma, dark areas
cooler This big ball of hot gas
is 1.4 million km in diameter
across, so 109 time the earth
diameter. It has a mass of 2
million-trillion-trillion-trillion
kilograms, it weighs as much
as 330 000 Earths. About 1
300 000 Earths would fit
inside the Sun.