The document provides an overview of the universe and some of its key components. It defines the universe as all matter and energy, including planets, stars, galaxies and intergalactic space. Scientific observations have led to inferences about the early stages of the universe, supported by the Big Bang theory which describes the formation of the universe approximately 13.77 billion years ago. Stars are fundamental building blocks of galaxies and are responsible for producing heavy elements. Galaxies are massive gravitationally bound systems consisting of stars, gas and dust, with the Milky Way being the galaxy that contains our solar system.
1. The
Universe
By : Che Wan, How Qi Ming,
Imran, Harvin, Pavitran
Teacher : Mrs. Shanti
2. Definition
The Universe is commonly defined as the
totality of existence, including planets, stars,
galaxies, the contents of intergalactic
space, and all matter and energy.
Definitions and usage vary and similar terms
include the cosmos, the world and nature.
3. How much does man know
about the universe?
Scientific observation of the Universe, the
observable part of which is about 93 billion
light years in diameter, has led to inferences
of its earlier stages. The Big Bang theory is
the prevailing cosmological model that
describes the early development of the
Universe, which in physical cosmology is
believed to have occurred about 13.77
billion years ago.
6. What is a star?
Stars are the most widely recognized
astronomical objects, and represent the
most fundamental building blocks of
galaxies. Stars are responsible for the
manufacture and distribution of heavy
elements such as carbon, nitrogen, and
oxygen. Consequently, the study of the
birth, life, and death of stars is central to the
field of astronomy.
7. Formation of Stars
Star formation begins when the denser parts
of a cloud core collapse under their own
weight/gravity. The cores are denser than
the outer cloud, so they collapse first. As the
cores collapse they fragment into clumps.
These clumps then form into protostars and
the whole process takes about 10 millions
years.
8. Star explosions
The explosion of a Star is called Supernova.
Nova means "new" in Latin. Supernovae are
extremely luminous and cause a burst of
radiation that often briefly outshines an
entire galaxy, before fading from view over
several weeks or months.
9. Star explosions continued…
A black hole is a region of
spacetime from which gravity
prevents anything, including
light, from escaping. Around
a black hole there is a
mathematically defined
surface called an event
horizon that marks the point
of no return. It is called "black"
because it absorbs all the
light that hits the horizon,
reflecting nothing, just like a
perfect black body.
11. What is a Galaxy?
A galaxy is a massive, gravitationally bound
system consisting of stars, stellar remnants,
and interstellar medium of gas and dust,
and, it is hypothesized, an important but
poorly understood component called dark
matter. The word galaxy is derived from the
Greek galaxias (γαλαξίας).
12. Formation
Current cosmological models of the early
Universe are based on the Big Bang theory.
About 300,000 years after this event, atoms
of hydrogen and helium began to form, in
an event called recombination. But until
now, no one really does know for sure how
galaxies are formed.
13. The Milky Way
The Milky Way is the galaxy that contains
our Solar System. This name derives from its
appearance as a dim "milky" glowing band
arching across the night sky, in which the
naked eye cannot distinguish individual
stars. The term "Milky Way" is a translation of
the Classical Latin via lactea, from the
Hellenistic Greek
14. List of named galaxies…
Sagittarius
Andromeda
Ursa Major
Sculptor
Ursa Major
Sculptor
Serpens Caput
Ursa Major
Ursa Major
Virgo
Canes Venatici
Draco
Canes Venatici
16. What is Earth?
Earth is the third planet from the Sun, and
the densest and fifth-largest of the eight
planets in the Solar System. It is sometimes
referred to as the world, the Blue Planet, or
by its Latin name, Terra. And as everybody
knows, it’s the only planet known to man
which sustains life.
18. Continents
A continent is one of
several very large
landmasses on Earth.
The earth is made up
of 7 continents which
are Asia, the biggest
one, Antarctica the
coldest one, North and
South America, Africa
and last and the
smallest, Europe.
19. Climates
Climate is the
statistics of
temperature,
humidity,
atmospheric
pressure, wind,
precipitation,
atmospheric
particle count and
other
meteorological
elemental
measurements in a
given region over
long periods.
21. What is a comet?
Comets are objects
composed mostly of
ice and dust that
grow tails when they
approach the sun. All
comets have a
nucleus, which is the
hard rock/ice object.
22. What is an Asteroid?
Asteroids are the small
rocky objects in the
Solar System. The
largest asteroid is
Ceres, which is 933
kilometers. Many
asteroids, including all
of the largest asteroids,
orbit the sun between
Mars and Jupiter in the
Asteroid Belt.
23. What is a Meteor?
Meteor however, is a
small body of matter
from outer space
that enters the
earth's atmosphere,
appearing as a
streak of light. It’s
also called a
shooting star.