I really love this topic, so I made a presentation about what I know.

1. Unraveling the mysteries of our
Made by
Govind Joshi

2.  The Universe is everything that exists, including objects and
energy throughout time and space. The size of the universe is
difficult to imagine. It is so large that even light (travels
299,792, 458 m/s) from very distant objects in the universe must
travel billions of years before reaching the earth. The earth, sun,
and the moon are only a small part of the universe. Another name
for the universe is “Cosmos”. That is the reason Cosmology and
Astronomy are both the study of the universe. Astronomers are
scientists that study the universe. They use telescopes and many
other tools to study the universe. They also use information
collected during space exploration and by satellites.

3.  The Big Bang Theory

4. The Big Bang
Most Scientists believe that the universe
began suddenly in an event called the
“Big Bang”. They estimate this event
happened between 10 to 15 billion years
ago. At the time of the big bang, the
matter was tightly packed and hot. After
the big bang the matter began cooling
and expanding. Within minutes, particles
of matter formed atoms of hydrogen and
helium. These atoms later formed stars
which lead to the creation of planets.
Since then the universe has been cooling
and expanding. Some astronomers think
that the universe may stop expanding
and start contracting, but most
astronomers think that it will keep
expanding.

5.  What is a Star ?
 How is a star formed ?
 Different types of stars
 How are planets formed ?
 What is a Galaxy ?

6.  A star is a huge sphere of very hot,
glowing gas. Stars produce their
own light and energy by a process
called nuclear fusion. Fusion
happens when lighter elements are
forced to become heavier elements.
When this happens, a tremendous
amount of energy is created causing
the star to heat up and shine. Stars
come in a variety of sizes and colors.
Our Sun is an average sized
yellowish star. Stars which are
smaller than our Sun are reddish
and larger stars are blue.

7.  Clouds of gas (nebula) are disturbed
by the gravity of a nearby
phenomena. This disturbance causes
clumps to form and draw gas inward.
The collapsing clump begins to rotate
and flatten into a disc of gas and dust.
The disc rotates faster and faster
pulling more material inward
creating a hot, dense core called a
protostar. When the protostar
becomes hot enough, it starts
producing helium and energy. If
enough mass collapses into the
protostar, a bipolar flow occurs. Two
massive gas jets erupt from the
protstar and blast the remaining gas
and dust clear away from its fiery
surface. A Star is born.

8. Have you observed a candle before ? Well, look at it carefully. The
outermost part of the fire looks red (not so hot), the middle part looks
yellow (medium hot), and the innermost part looks blue (Very Hot).
Similarly, red stars are not so hot, yellow stars are medium hot, and
blue stars are very hot. These are the different types of stars :
Not so hot
Yellow Star Black Holes
White Dwarf Blue Stars Medium
hot
Giant Star Very hot
Neutron Star
Supergiant Star
Red Dwarf

9.  Our Sun is a yellow star.
Yellow Stars are medium-
sized stars and they look
yellow because they have
a medium temperature.
They burn their fuel fast
so they live up to 10
billion years.

10.  Stars with up to 3 times
the mass of the sun
continue fusing
hydrogen into helium in
their outer layers.
Therefore the hull heats Giant Star
up and is driven out into
space. The star expands
and increases brightness.
A Giant star is evolved.
The core is left behind as
White dwarf which White Dwarf
burns very little fuel and Note- White Dwarfs go Nova.
A star showing a sudden large increase
slowly fades away. in brightness and then slowly returning
to its original state over a few months.

11.  Supergiant stars are nothing
but stars that expanded and
increased their brightness
massively. Blue Stars are
very large and compact.
They burn their fuel very Supergiant Star
quickly so they are very hot.
Sometimes these stars can
run out fuel in only 10,000
years. Both of these stars die
in a spectacular way. They
supernova (massive
explosion) which can be seen
Blue Star
from galaxies away. Or they
shrink into black holes or
neutron stars

12.  Stars are sustained by the nuclear
fusions going on in their core
from their own gravity. After
they run out of almost all their
fuel, they collapse into their own
gravity. How much mass the star Black Hole
had when it died determines
what it becomes. Stars with up to
3 times the mass of the sun
become neutron stars. These
stars are very dense, they spin
Neutron Star
very fast, they do not glow, and
are made mostly of neutrons. Black Holes have so much
Stars with the mass of over 3 Gravitational pull that even
times the sun get crushed to a Light cannot escape the wrath
single point called a black hole. of black holes.

13.  Red Dwarfs are small
stars that burn a little
more fuel than white
dwarfs. They have a
mass of less than half
that of the Sun. They are
relatively cooler than
most stars. Proxima Proxima Centauri
Centauri , the nearest Red Dwarf
star to the Sun, is a red
dwarf.

14.  Planets are formed out of the remnants
of a star birth. When a star is in the
initial stages of being created, the
molecular cloud surrounding it begins
to rotate. As it rotates, the cloud will
begin to condense around areas where
there is more matter. These are called
“protoplanets. These protoplanets will
continue to accumulate more matter by
their gravitational pull which will keep
increasing as they get bigger. Once the Planet Forming
star is born, it will blow away the
remnants of the cloud leaving only the
protoplanet. Depending on its size, the
protoplanet will become a moon,
asteroid, comet, or planet.

15.  The sun is in a group of stars known as
the Milky Way galaxy. A galaxy is a large
system of stars, gas, planets, asteroids,
and dust. The Milky Way galaxy alone
contains more than a 100 billion stars.
Some galaxies are larger, and some are
much smaller. But even small galaxies
contain hundreds of millions of stars.
Galaxies also have many different
shapes. The Milky Way galaxy looks like
a milk spill. Until the early 1900s
scientists did not know that there were The Milky Way Galaxy
galaxies outside the Milky Way. By using
powerful telescopes, scientists now
estimate that there are over billions of
galaxies in the universe. The Andromeda
galaxy is the closest galaxy to the Milky
Way.

16. The Andromeda
Galaxy
The Andromeda galaxy is a spiral galaxy and it
contains about 1 trillion stars

17.  The Solar System
 The Planets and their moons
 The Earth’s moon
 Asteroids and comets

18.  The Solar System consists of
the Sun, Moon, and Planets.
It also consists of comets,
meteoroids, and asteroids.
The Sun is the largest
member of the Solar System.
In order of distance from the
Sun, the planets are Mercury,
Venus, Earth, Mars, Jupiter,
Saturn, Uranus, Neptune,
and Pluto; the dwarf planet.
The Sun is at the center of
the Solar System and the
The Solar System
planets, asteroids, comets
and meteoroids revolve
around it.. Other planets that
orbit other stars are called
exoplanets.

19.  These are all the planets in order (distance from
the sun) :
Inner Planets (made of rock)
Mercury Venus Earth Mars
Outer Planets (made of gas)
Jupiter Saturn Uranus Neptune

20. MERCURY VENUS
 1 Orbit of Sun-87.969 Days  1 Orbit of Sun-224.701 Days
 1 Rotation-58.6461 Days  1 Rotation-243.16 Days
 Distance from Sun-57 million km  Distance from sun-107 million km
 Moons-0  Moons-0
EARTH MARS
 1 Orbit of Sun-365.3 Days  1 Orbit of Sun-686.98 Days
 1 Rotation-23 hrs. 56 min  1 Rotation- 1.37 day
 Distance from Sun-150 million km  Distance from sun-229 million km
 Moons-1  Moons-3

22. JUPITER SATURN
 1 Orbit of sun-4332.59 Days  1 Orbit of sun-10759.2 Days
 1 Rotation-9 hrs. 55 min  1 Rotation-10 hrs. 13 min
 Distance from sun-777 million km  Distance from sun-1429 million km
 Moons- 63  Moons- 47
URANUS NEPTUNE
 1 Orbit of sun-30684 Days  1 Orbit of sun-60190 Days
 1 Rotation-17.2 hrs.  1 Rotation-16 hrs. 17 min
 Distance from sun-2871 million km  Distance from sun-4496 million km
 Moons- 27  Moons- 13

23. Outer Planets

24.  The Moon is a barren, rocky
world without air and water.
It has dark lava plains on its
surface. The Moon is filled
with craters. It has no light of
its own. It gets its light from
the Sun. The Moon looks like
it is changing its shape as it
moves round the Earth. It
spins on its axis in 27.3 days.
Neil Armstrong and Edwin
Aldrin were the first ones to
set their foot on the Moon on
21 July 1969 They reached The Moon
the Moon in their space craft
named Apollo II.

25. Asteroids and comets are
considered remnants from the
giant cloud of gas and dust that
condensed to create the sun,
planets, and moons some 4.5
billion years ago. Today, most
Asteroid
asteroids orbit the sun in a tightly
packed belt located between Mars
and Jupiter. Comets are relegated
to either a cloud or belt on the solar
system fringe. Gravitational tugs,
orbital collisions, and interstellar
jostles occasionally perturb an
asteroid or comet onto a wayward Comets
path.

26. Black Hole eating a huge star
Light from a nearby
Supergiant Star
Largest Black hole
known to man
Nebula Crab Nebula
Biggest Nebula known
To man

27.  There is a lot more to
learn about the
universe and a lot of
mysteries to solve. So
I hope you enjoyed
the show !
Horsehead Nebula
Millions of
different
galaxies