Presentation Example on Astronomy

Slide 2: OUR SUN

At the center of the universe, lies the Sun, which is the largest object in the Solar System. The star contains 99.8% of the total mass of the Solar System (Jupiter contains most of the rest). All the elements of the universe from the smallest particles to the largest planets are held together in their orbits by the Suns Gravity. Together with the Universe, the sun was formed from the solar nebula (a huge cloud of gas). Upon its collapse, the nebula was flattened into a disk by gravity, with most of the materials being pulled to the center. This is how the sun was formed.

Slide 3: OUR SOLAR SYSTEM

There are nine planets in the Solar System. The other objects include moons, asteroids, comets and meteoroids. Our Solar System was formed through a cloud of interstellar gas and dust. It is through this formation that objects in the Solar System assumed their positions. All the objects that orbit the sun (directly or indirectly) are gravitationally bound.

Slide 4: OUR GALAXY: THE MILKY WAY

Galaxies range in sizes from hundred million stars to trillion stars. All these stars orbit the underlying galaxys center of mass. It is almost impossible to count the exact number of stars in the Milky Way but there are approximately 100 billion stars.

These stars form a large disk whose diameter is about 100,000 light years. Our Solar System is about 25,000 light years away from the center of our galaxy. The Sun goes around the center of the Milky Way. It takes 250 million years for our Sun and the solar system to go all the way around the center of the Milky Way.

Slide 5: NEXT CLOSET GALAXY

The Andromeda Galaxy has been known to humans for an extended period of time due to the fact that it can be spotted by the naked eye. In 1920 Edwin Hubble, an astronomer, confirmed the galaxy, refuting contentions that it was a gas cloud in the Milky Way.

Slide 6: BEGINNING OF THE UNIVERSE

The Big Bang theory, therefore, explains the beginning of the universe from the earliest known periods through the progressive evolutions over the centuries. The abundance of light elements, the cosmic microwave background (CMB), large scale structure, and Hubble's law were imperative aspects of the Big Bang Theory. Dark Energy emanated from the emptiness of space (Matter has the effect of pulling space together so it contracts).

Slide 7: EVOLUTION OF THE UNIVERSE

At this initial stage when the universe was undergoing the primary growth spurt, it grew approximately 90 times its size. As the universe expanded, it got cooler and denser. According to, SPACE.com 2017; As the universe expanded, temperatures cooled and protons and neutrons collided to make deuterium, which is an isotope of hydrogen. Much of this deuterium combined to make helium.

Slide 8: SIZE AND SCALE OF THE UNIVERSE

The earth is 12,700 km in diameter while the Sun on the other hand is 12,700 km in diameter. The region of the Galaxy within about 20 lightyears of the Sun (40 lightyears diameter). The Milky Way Galaxy comprises of 100,000 light-years across and 1,000 light-years thick. The Sun is located at the edge of a spiral arm, 30,000 lightyears from the center. There are over 200 billion stars in the Milky Way galaxy. The local Group of Galaxies is approximately 6.5 million light-years in diameter.

Slide 9: CONTENT OF UNIVERSE

There are at least 100 billion galaxies in the Universe. Astronomy and Surveys of galaxies depict a web-like or honeycomb structure to the Universe. Computer simulations also show a similar structure, often referred to as the Cosmic Web.

Slide 10: CONTENT OF UNIVERSE

The local group of galaxies contains 3 large spiral galaxies (Milky Way, Andromeda, and Triangulum). There are also an array of dwarf galaxies with elliptical or irregular shapes. The local supercluster is a huge cluster of thousands of galaxies.

Slide 11: THE END OF THE UNIVERSE

In the "Big Freeze", the universe ends up uniformly cold, dead and empty. The General Relativity theory affirms that the universe as a whole must either be expanding or contracting. It could not stay the same size. A contracting universe will see it reduce in size, become denser, and hotter leading to the big crunch.

Slide 12: REFERENCES