Big Bang

timeline

Big Bang Timeline

13.7 billion years ago – Before the Big Bang, the universe was a hot point ( ) of pure energy :

Tremendous levels of radiation and heat prevented particles of matter from forming.

Big Bang Timeline

10 - 32 sec after the Big Bang

“Quark Soup”

The 4 forms of energy separate

leaving a superhot, charged plasma

of the tiniest particles of matter:

Quarks

Leptons – electrons & neutrinos

Big Bang Timeline

10 - 32 sec – “Quark Soup”

Big Bang Timeline

(This mess is nicknamed “Quark Soup”.)

The Universe is still only the size of a

tennis ball at this point,

but it’s growing like crazy!!)

Big Bang Timeline10 - 6 sec (1/1,000,000 sec) – 1 sec after Big Bang

As the universe expands, it cools off quickly.

The ambient temperature in the universe drops to a mere 1 trillion degrees…

…as the Universe has expands rapidly until it

reaches 80 billion miles across.

Big Bang Timeline

10 - 6 sec (1/1,000,000 sec) - 1 sec after the Big Bang

It is cool enough that

quarks collide and join

to form protons &

neutrons

Proton

Neutron

Big Bang TimelineThese protons are the first atomic

nuclei (of hydrogen atoms).

Most hydrogen atoms are as old as the universe.

Proton

Big Bang Timeline

10 - 6 sec (1/1,000,000 sec) - 1 sec ( continued)

Note: At the same time: anti-quarks joined to form anti-protons and anti-neutrons.

Big Bang Timeline

10 - 5 sec (1/100,000 sec) (cont.)

Much of the matter and all of the

anti-matter annihilated each other,

filling the universe with huge amounts of

radiation.

Big Bang Timeline

10 - 5 sec (1/100,000 sec) (cont.)

Much of the matter and all

of the anti-matter

annihilated each other,

filling the universe

with huge amounts of

radiation.

Big Bang Timeline

3 sec - 20 minutes after the Big Bang

Universe expands to form a

thermonuclear fireball

1.3 trillion miles across!

3 sec - 20 minutes after the Big Bang

Universe expands to form a

thermonuclear fireball

1.3 trillion miles across!

Big Bang Timeline

3 sec - 20 minutes after the Big Bang

Neutrons and Neutrons and protons collide and finally stick together to form Helium (He) nuclei…

(held together by the strong nuclear force)(held together by the strong nuclear force)

Big Bang Timeline3 sec - 20 minutes after the Big Bang

…(and just a handful of Lithium (Li) nuclei).

Evidence: The universe is still

99.9 % H and He today.)

(92.7 % H and 7.2 % He)

3 sec - 20 minutes after the Big Bang Primordial Nucleosynthesis

Neutrons and Neutrons and protons collide to form Helium (He) nuclei…

Big Bang Timeline

He

3 sec - 20 minutes after the Big Bang Electrons are flying around unattached to atoms, trapping photons of light, ultraviolet and x-ray radiation and keeping the universe opaque.

Big Bang Timeline

opaque.

Big Bang Timeline

3 sec - 20 minutes after the Big Bang

As the fireball expands to a couple of

1000 times bigger than our solar

system:

Temperatures drop below

1 billiono C for the first time.

Big Bang Timeline

3 sec - 20 minutes after the Big Bang

These “cooler” temperatures cause

fusion reactions to stop before larger

elements can form.

Evidence: the universe is still

99.9 % Hydrogen & Helium today!

Big Bang Timeline

380,000 years later -Temperature drops to 3000o C.

The universe had grown a lot,

but it was still 1000 X smaller

than it is today.

Big Bang Timeline

380,000 years later -Temperature drops to

3000o C.

Electrons slow

down…

380,000 years later -…and start to orbit the

atomic nuclei to make atoms of hydrogen,

helium

and

lithium.

Big Bang Timeline

Helium

Lithium

Big Bang Timeline

380,000 years later – continued

Matter and energy decouple (separate from each other) as atoms form.

Photons of light and neutrinos stopped interacting with electrons and are no longer “trapped”.

Big Bang Timeline380,000 years later – continued

This decoupling released huge amounts of gamma rays and cosmic rays.

Decoupling also cleared up the universe, which became transparent. transparent

Big Bang Timeline

380,000 years later – continued– continued

This high energy radiation has This high energy radiation has

cooled off to become thecooled off to become thecosmic background microwave radiation

still seen today.still seen today.

Big Bang Timeline380,000 years later – continued

cosmic background microwave radiation

1967 - discovered by Penzias and WilsonStudied in greater detail, first by the COBE

and more recently by the WMAP space exploration projects.

These images show the universe as it appeared 13.7 billion years ago.

(See next frame.)

Cosmic Background Microwave Radiation(WMAP Satellite Shows a More Detailed Image)

COBE

WMAP

Big Bang Timeline

1 Billion Years Later (12.7 b.y. ago)Gravity causes clouds of H and He

condense into lumpy pockets called

galaxies (about 100 billion of them!).

(The pockets of intense radiation on the WMAP are thought to be the sources of the first galaxies.)

Deep Field Telescope View of the Early Galaxies

Big Bang Timeline3 Billion Years After the Big Bang…

Within each galaxy, smaller balls of H and He gas were pulled inward by gravity.

Heat from the gravitational compression caused thermonuclear reactions and the first stars were formed. The first stars were entirely Hydrogen & Helium.

Big Bang Timeline

9.1 Billion Years After the Big Bang (4.6 billion years ago)

Earth’s Sun and Solar System formed after

750 generations of stars

had come and gone.

9.1 Billion Years After the Big Bang… (4.6 billion years ago)

(Our sun is made up

of a lot of “recycled”

parts from earlier stars,

not just H & He, but

Li, C,O, Na, Ca, Fe

and many others.

Big Bang Timeline

Big Bang Timeline

Pure Energy

“Quark Soup”

He & Li Nuclei

Atoms Form

The Skies Clear…

Today

10-6 sec

1st Protons (H Nuclei) & Neutrons

3 min

380,000 years

First Galaxies

First Stars

3 Billion Years

13.7 Billion years

Our Sun

9 Billion Years

Not Enough Matter

Just Enough Matter

Too Much Matter

Matter & the Fate of the Universe

A Stanmo ProductionThanks to NASA and JPL for the great pix.

2008