Download The Components and Origin of the Universe

The Components and
Origin of the Universe
Earth in the Universe
Formation of the Solar System

Solar Nebula Theory:

Solar system formed 5 billion years ago from
a massive cloud of gas and dust that began to
contract
http://www.youtube.com/watch?v=B1AXbpYndGc&gl=GB&hl=en-GB
Evidence

Theory explains observations that the
planets orbit the Sun in the same direction,
the planets are all in the same plane, Sun
is at the centre, most planets rotate the
same way, terrestial are closer than gas
The Organization of the
Universe
1.
Stars and Solar Systems
 most common type of celestial object
2.
Star Clusters
 groups of stars that formed in the same nebula
and are gravitationally bound
Open star
clusters –
groups of 6 to
1000’s of
young stars
Globular star
clusters – groups
of 1000’s to
millions of older
stars
The Organization of the
Universe
Galaxies
 collections of star clusters,
planets, gas and dust
measuring up to 100 000
light years across.
 there are different kinds
3.
Elliptical - contain the
oldest stars but little gas or
dust
Spiral (like the Milky Way) many bright, young stars
with lots of gas and dust
The Organization of the
Universe
3.
Galaxies
Lenticular – central bulge
but no spiral arms
Irregular – no definite shape
The Organization of the
Universe
4.
Galaxy Clusters
 galaxies, like stars, are grouped together
 the Milky Way and our closest neighbouring galaxy
Andromeda are part of the Local Cluster
 local clusters are then grouped into Super Clusters
and so on
How many stars are in the universe? Well…
300 billion stars x 200 billion galaxies =
1.0 x 1022 stars (20 sextillion stars)
The Organization of the
Universe
Our Expanding Universe:
 we
know the universe is expanding due to the
phenomenon of the Doppler Effect
 as a fire truck goes past you, its pitch changes
(click)
The Doppler Effect and Light
 the
same thing happens with light energy
 energy travelling towards you has a shorter
wavelength because it is compressed (bluer light)
 energy going away from you has a longer wavelength
(redder light)
 this is called the RED SHIFT
 we see a red shift in the light from distant stars
therefore, they are moving away from us
The Doppler Effect and Light
Hubble’s Law
 based
on this evidence, Edwin Hubble proposed
HUBBLE’S LAW
 the farthest galaxies are moving away the fastest and
the closest are moving away the slowest
 think of raison bread dough…….you are sitting on a
single raison and so it appears you are sitting still
 The
red shift and
expanding universe are
part of the evidence of
the Big Bang – a theory
explaining how the
universe originated.
Dark Matter and Dark Energy
scientists were puzzled when some galaxies appeared to be
moving away faster than they should be
 the deduced there must be upwards of 10x more mass in a
galaxy than we can see
 they called this mass dark matter
 we now know it is the most abundant matter in the
universe but we don’t know much about it

before 1998 scientists thought the pull of gravity would
eventually slow the expansion of the universe down
 however, in 1998, they discovered that not only is the
universe expanding but it gets faster as it goes
 this strange energy working against the force of gravity
was called dark energy

Origin of the Universe

The Big Bang:

Universe began in an incredibly hot, dense
expansion approximately 13.7 billion years
ago
http://www.youtube.com/watch?v=lhTSfOZUNLo
No, not this one
This one…
The Big Bang Theory
the Big Bang Theory suggests that all matter and
energy expanded from a hot dense mass with an
incredibly small volume
2. at first, the universe was hot (10 32 C) and energy
went rushing out in all directions
energy became cooled enough to become matter
3. matter then cooled enough to form protons, electrons
and neutrons (subatomic particles)
4. subatomic particles combined to form mostly
hydrogen but some helium nuclei
1.
Evidence of the Big Bang
 the
universe is filled with gas and as a gas expands it
cools  the universe is cooling
 the red shift shows that galaxy’s are moving away
from us universe if growing
 we have detected cosmic background radiation that
was left over from the intense radiation created
during the Big Bang  we can hear it
 we
have found no stars
that are older than the
age we think the universe
is  we’re smart
Your Task
P. 391 #5 -8
 P. 397 #1-6, 8-10
