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“Astronomy is more than the study of stars and
planets. It is the study of the universe in which we
humans exist. You and I live on a small planet circling
a small sun drifting through the universe, but
astronomy can take us beyond these boundaries and
help us not only see where we are in the universe but
understand what we are. ”
- Michael A. Seeds, Astronomer-
THE HISTORY OF THE UNIVERSE IN
ONE EASY LESSON
THE BEGINNING, WHERE WE
ARE, AND THE END
COSMOS - GREEK WORD FOR ORDER
WE LOOK AT PRETTY MUCH THE SAME NIGHT
SKY THAT OUR ANCESTORS LOOKED AT.
THE CLOSER WE LOOK, THE MORE
COMPLICATED IT BECOMES, AND WE THINK
ANYTHING BUT ORDER.
IT’S AN EXTREMELY COMPLEX PLACE OUT
THERE - ALMOST MIND BOGGLINGLY SO.
IN DOUGLAS ADAMS’S HITCHHIKER’S GUIDE
TO THE GALAXY THE ULTIMATE TORTURE
MACHINE IS KNOWN AS THE TOTAL
PERSPECTIVE VORTEX - A DIABOLICAL
CREATION THAT CAN TURN ANY LIVING
BEING INTO A RAVING LUNATIC.
INSIDE THE CHAMBER IS A PICTURE OF THE
ENTIRE VASTNESS OF THE COSMOS WITH A
TINY ARROW THAT READS “YOU ARE HERE.”
SCIENTISTS BASE THEIR THEORY OF THE BIG
BANG ON THE FACT THAT THE UNIVERSE IS
EXPANDING.
IF YOU GO BACK IN TIME, YOU WOULD REACH
A POINT WHERE THE UNIVERSE WAS
COMPRESSED INTO A SINGLE POINT.
NOW, AS YOU MOVE FORWARD FROM THAT
POINT IN TIME, AND FOLLOW THE UNIVERSE
AS IT EXPANDS, EACH POINT IN TIME
REPRESENTS A CERTAIN ENERGY OR
TEMPERATURE.
THE TEMPERATURES OR ENERGY LEVELS WERE
SO GREAT AT FIRST THAT MATTER AS WE
KNOW IT COULD NOT EXIST.
ALL CIVILIZATIONS HAVE HAD THEIR
CREATION STORIES TO EXPLAIN HOW IT ALL
BEGAN.
IT ALL BEGINS WITH NOTHING - NOTHING AT
ALL.
THIS IS SIMILAR TO MANY CREATION
STORIES.
IT BEGINS WITH A SINGULARITY - A TINY
SEED THAT CONTAINED ALL THE MATTER
BUT, REMEMBER THERE WAS NOTHING - NO
SPACE; NO TIME; NOT EVEN A VOID NOTHING AT ALL.
IN AN INSTANT, NOTHING BECAME
SOMETHING.
At 5 seconds, NUCLEI OF ATOMS BEGAN TO
FORM.
DURING THIS TIME, DEUTERIUM, HELIUM-3,
HELIUM-4, AND LITHIUM NUCLEI WERE
FORMED.
AFTER 5 MINUTES, THE UNIVERSE HAD COOLED
TO THE POINT THAT PROTONS AND NEUTRONS
DID NOT HAVE ENOUGH ENERGY TO STICK
TOGETHER ON COLLISION.
NUCLEOSYNTHESIS ENDED AT THIS POINT.
A CLOUD OF NUCLEI, ELECTRONS, PROTONS,
AND PHOTONS EXISTED AT THIS POINT - A
PLASMA.
PLASMAS HAVE INTERESTING PROPERTIES THEY CONDUCT ELECTRICITY (LIKE METALS),
AND THEY ARE OPAQUE TO LIGHT.
AT THIS POINT, 75% OF MATTER WAS
HYDROGEN NUCLEI AND 25% WAS HELIUM
NUCLEI.
THE UNIVERSE CONTINUED TO EXPAND AND
COOL.
AT APPROXIMATELY 300,000 YEARS, THE
UNIVERSE COOLED ENOUGH FOR ATOMS TO
FORM.
THE PLASMA DISSAPEARED, AND PHOTONS
COULD ESCAPE.
PHOTONS ZOOMED OFF IN ALL DIRECTIONS.
AT APPROXIMATELY A HALF BILLION YEARS,
STARS COULD FORM.
AT APPROXIMATELY 1 BILLION YEARS,
GALAXIES COULD FORM.
@ 10-33 sec, T = 1027 K, UNIVERSE ~ 100 cm
wide
@ 1 sec, T = 1010 K, UNIVERSE ~ 1020 cm wide
@ 300,000 years, T = 3,000 K
THE HUBBEL
TELESCOPE HAS
MADE TWO
VERY LONG
EXPOSURES
THAT HAVE
ALLOWED
ASTRONOMERS
TO LOOK BACK
APPROXIMATELY
12.5 BILLION
YEARS IN TIME.
DATA SUPPORTING BIG BANG THEORY:
1.THE UNIVERSE IS EXPANDING.
2.COSMIC MICROWAVE BACKGROUND
RADIATION
3.CHEMICAL COMPOSITION OF THE UNIVERSE
– 75% HYDROGEN, 25% HELIUM, TRACE OF
LITHIUM.
4.TEMPERATURE OF SPACE
OUR OWN GALAXY, THE MILKY WAY, PROBABLY
FORMED FROM A CLOUD OF GAS.
THE CLOUD WAS PROBABLY SPHERICAL AT ONE
TIME, AS WE DO SEE SOME OLDER STARS IN A
SPHERICAL HALO AROUND THE OUTSIDE OF
OUR GALAXY.
AS THE CLOUD STARTED TO ROTATE, IT
FLATTENED OUT.
STARS IN OUR GALAXY FORMED, AND SOME
GREW OLD AND DIED.
THESE CONTRIBUTED THEIR MATTER TO GAS
CLOUDS THAT FORMED NEW STARS.
STARS HAVE A FINITE LIFETIME.
THEY ARE FUELED BY NUCLEAR FUSION
REACTIONS.
LIGHT NUCLEI COLLIDE AT VERY HIGH SPEEDS
TO FORM HEAVIER NUCLEI.
IN THE PROCESS, A GREAT DEAL OF ENERGY IS
RELEASED.
IT’S THIS ENERGY THAT KEEPS STARS FROM
COLLAPSING.
WHEN A STAR USES UP MOST OF ITS NUCLEAR
FUEL, THERE IS NOT ENOUGH ENERGY
PRODUCED TO OVERCOME GRAVITY, SO THE
STAR WILL COLLAPSE.
THERE ARE 2
WAYS A STAR CAN
DIE.
1. IF A STAR IS
APPROXIMATELY
10 TIMES THE
MASS OF OUR
SUN, WHEN IT
COLLAPSES, IT
WILL GO SUPER
NOVA - A HUGE
EXPLOSION.
2. 3 TIMES THE MASS OF OUR SUN OR
SMALLER, IT WILL EXPAND TO BECOME A RED
GIANT, THEN PUFF OFF ITS OUTER LAYERS AND
BECOME A WHITE DWARF.
THE MILKY WAY GALAXY - HOME
THE LOCAL GROUP
THE ANDROMEDA GALAXY AND THE MILKY WAY
GALAXY ARE 2 MILLION LIGHT YEARS APART.
IN KILOMETERS, THAT WOULD BE:
2 X 106 X 9.5 X 1012 = 1.9 X 1019 KM
THEY ARE MOVING TOWARDS EACH OTHER
AND WILL COLLIDE IN APPROXIMATELY 5
BILLION YEARS.
NOT IN OUR LIFE TIME, IN OTHER WORDS!
THE VIRGO CLUSTER, ALONG WITH SEVERAL
OTHER CLUSTERS ARE MOVING TOWARDS A
REGION OF SPACE THAT DOES NOT CONTAIN
ANYTHING THAT WE CAN SEE.
ASTRONOMERS REFER TO THE OBJECT
TOWARDS WHICH THE GALAXIES ARE MOVING
AS “THE GREAT ATTRACTOR.”
WHAT DOES ALL OF THIS MEAN FOR THE
FUTURE?
IT MEANS THAT WE LIVE IN AN EXPANDING
UNIVERSE, AND THE EXPANSION IS SPEEDING
UP.
IN A SENSE, THE SPACE BETWEEN THE
GALAXIES IS GETTING LARGER.
IN THE FUTURE, STARS WILL BURN UP.
OUR OWN SUN WILL USE UP MOST OF ITS
FUEL IN ABOUT 5 BILLION YEARS.
AS SPACE EXPANDS, GALAXIES WILL MOVE
FURTHER APART.
STARS WILL GO OUT.
THE NIGHT SKY WILL BECOME EMPTIER AND
EMPTIER.
ENERGY WILL BECOME HARDER TO FIND.
THIS IS NOT QUITE THE SCENE DEPICTED IN
“THE RESTURANT AT THE END OF THE
UNIVERSE.”
THE LIFE OF OUR UNIVERSE IS ABOUT 14
BILLION YEARS.
LIGHT SIGNALS HAVE NOT HAD TIME TO
TRAVEL MORE THAN 14 BILLION LIGHT YEARS.
SO, WE CAN’T OBSERVE ANYTHING OUTSIDE OF
THIS SPHERE.
“Our currently observable universe is but one small
part of a greater whole. But if the laws of physics
can enforce the production of our universe, these
same laws could create a whole series of universes
through the same mechanism. These other
universes, the offspring of other small patches of
space-time being launched into existence, could
evolve and never come into contact with our own.”
- Fred Adams-
THE UNIVERSE IS A VERY
STRANGE PLACE INDEED.
MIND-BOGGLING!!!