The planets make up only 0.135 % of the mass in our solar system. The Sun dominates, accounting for 99.86 % of the entire solar system's mass.

Did you know that…?

SOLAR SYSTEMS, GALAXIES AND THE UNIVERSE

OUR SUN is one of millions of stars that orbit the centre of…

THE MILKY WAY, which is one of a billion galaxies that orbit and move away from the centre of…

THE UNIVERSE

(Basically, everything in the universe orbits around something else)

The Sun is in a galaxy called The Milky Way. Almost all the stars which can be seen from the Earth are part of this galaxy.

The Sun is 150 million kilometres away from us.

It has a massive diameter of 1,393,000 km.

Our Sun was probably formed from a large cloud of gas about 5,000 million years ago.

THE SUN

Why is sun a STAR?

How is it to be a STAR?

What proves that SUN is a STAR?

Made of light gases.

Made of gases – hydrogen and helium

Emits light and heat

Nuclear reaction in the core turns hydrogen atom into helium thus, creating vast amount of energy (including heat and light)

Sphere of hot gas

Sun is not solid but a dense mass of gas.

CHROMOSPHERE

PHOTOSPHERE

CORONA

CORE

PROMINENCES

Radiating Zone

SUNSPOTS

THE SUN and Its PARTSThe innermost portion is the core. This is

the hottest part. This is surrounded by ring of hot gases called the convection zone.

The visible surface of the sun is called the photosphere. This is where the diameter of the sun is measured.

The next layer is bright red in color and is called the chromospheres.

The outermost layer is the sun’s crown or corona. It is seen as a faint silver white light.

Prominences is a huge arch of gas that appears to shoot outward from the chromospheres.

All planets (apart from Pluto) orbit in the same plane… solar system is flat

All planets orbit the Sun in same sense.

The Sun and all planets (apart from Venus and Uranus) rotate in the same sense as the planets orbit the Sun.

Inner planets are small and rocky, but outer planets are large and gassy.

Planets’ orbits are elliptical

There are eight planets in our solar system:

SUN

Inner Planets: Mercury, Venus, Earth, MarsOuter Planets: Jupiter, Saturn, Uranus, Neptune

This planet is Mercury. The small rocky planet is the closest planet to the sun.

Like our moon, Mercury has almost no atmosphere.

Mercury is the smallest planet in the solar system.

MERCURY

This planet is Venus. If you would look at Venus and Earth they would look like they would be twins.

Venus is covered by thick, rapidly spinning clouds that trap surface heat, creating a scorched greenhouse-like world with temperatures hot enough to melt lead and pressure so intense that standing on Venus would feel like the pressure felt 900 meters deep in Earth’s oceans.

VENUS

Earth is our home planet. It is the only planet known in our solar system that has life.

Some facts are well known. For instance, Earth is the third planet from the sun and is the fifth largest planet.

EARTH

Mars is a small rocky planet. Sometimes there are great dust storms on Mars although scientist are sure Mars once had water. Scientist believe that 3.5 billion years ago, Mars had the largest flood in the solar system. Mars also has two small moons, Phobos and Deimos.

MARS

Jupiter is almost a “mini solar system.” It has many moons and rings. Jupiter is the biggest planet in our solar system. It looks a lot like a small star. In fact, if Jupiter had been between fifty to one hundred times more massive, it would have become a star rather than a planet.

JUPITER

This planet is Saturn. Saturn is a gas giant made mostly of hydrogen and helium. Saturn has rings that are made mostly of water ice. The particles in the rings range in size from dust mites to houses! Saturn has at least 60 observed satellites.

SATURN

This planet is Uranus. Uranus is known as a “gas giant” because it has no solid surface. It gets it’s blue-green color from methane gas above the deep cloud layers. Methane absorbs red light and reflects blue light. Uranus has about 20 moons.

URANUS

This planet is Neptune. Neptune was discovered in 1846. Neptune orbits the sun every 165 years. Neptune has the smallest diameter of our solar system’s giant gas planets (including Jupiter, Saturn, and Uranus).

NEPTUNE

PLANETS

MEAN DISTANCE FROM THE

SUN (miles)

ORBITAL PERIOD

MEAN TEMPERA-

TURE(°C)

DIAMETER

MERCURY 35,980,000 88 days 179 3,031 mi

VENUS 67,230,000 243 days 482 7,520 mi

EARTH 92,960,000 365.26 days 15 7,926 mi

MARS 141,700,000 687 days -63 4,220 mi

JUPITER 483,700,000 11.86 years -121 88,846 mi

SATURN 886,700,000 29.46 years -125 74,901 mi

URANUS 1.784 billion 84.01 years -193 31,765 mi

NEPTUNE 2.794 billion 165 years -193 to -153 30,775 mi

Asteroids - are millions of small planet-like bodies. Asteroids are not a star. They are rock, irregularly-shaped objects. They are minor planets. Their sizes differ. They are found between the orbits of Mars and Jupiter.

Other Members of the Solar System

Comets – are small bodies of nonvolatile grains and frozen gases. Their orbits bring them very close to the Sun and deep into space, often beyond the orbit of Pluto. They have different structures, but they all develop a surrounding cloud of material that usually grows in size and brightness as they approach the Sun. Usually, there is a bright nucleus in the middle of this material. The material and the nucleus form the head of a comet. As comets approach the sun, comets develop tails of luminous material that extend for million of kilometers from the head.

Meteoroids – are small pieces of stone or metal travelling in space. Most meteoroids are fragments from comets or asteroids that broke off from crashes in space with other objects. A few are actually chunks that blew of the Moon or Mars after an asteroid hit. When a meteoroid enters the earth’s atmosphere, it usually burns up completely. This streak of light is called a meteor, or shooting star. If a piece of a meteoroid survives its trip through our atmosphere and lands on earth, it is called a meteorite.

The sun is the center of the solar system.

The sun is the only star in the solar system.

The sun is a sphere of hot, light gases (hydrogen and helium) which emits light and heat.

There are 4 layers of the sun from the center: the core, the photosphere, the chromospheres and the corona.

LET’S SUM UP!

There are 8 planets in the solar system – (inner) Mercury, Venus, Earth, Mars, (outer) Jupiter, Saturn, Uranus, Neptune

Inner planets are rocky while outer planets are gaseous.

Planets differ in their distances from the sun, sizes and temperature.

Important FACTS:

The distance of a planet from the sun affects its period of revolution. The nearer the planet to the sun, the shorter its period of revolution; the farther the planet from the sun, the longer its period of revolution.

Earth is the only planet where life exists.

Earth is the densest planet.

Surface or cloud temperature of the planets differ depending on their distances from the sun. Thus, the closest the planet to the sun, the hottest is its temperature.

Although Mercury is the nearest to the sun, Venus is the hottest because Venus is covered with thick clouds of carbon dioxide which traps the heat absorbed from the sun.

Thank you!!!Marites M. Aday

Master Teacher INaujan West

signing off….