Facts about the universe and our solar system

THE SOLAR SYSTEM

UNIVERSE

The universe is the totality of existence (planets, stars, galaxies)

The observable universe is 46 billion light years in radius and is

constantly expanding

It is estimated that the universe is 13.7 billion years old!

MILKY WAY

Galaxies are large systems of stars, dust and gas bound by gravity

The Milky Way is just 1 galaxy containing the Solar System,

25,000 light years from the centre of the galaxy

There are more than 170 billion galaxies in the observable universe

PLANET ORDER

36 millio

n

67.2 m

illion

93 millio

n

141.6 m

illion

483.6 m

illion

888.2 m

illion

1.8 bil

lion

2.8 bil

lion

& distance from the sun (miles)

SUN

The estimated diameter of the sun is 695,508km (109.2 x that of Earth)

The light from the sun takes 8 minutes to reach the earth

If the sun were hollow, we could fit 1.3 million Earths

inside the shell!

MOON

The Moon was formed 4.6 billion years ago, much later

than the Solar SystemWe only ever see one side of the moon. This is due to the moon being in synchronous

rotation with Earth

The first Moon landing was in 1969 by the USA. Man hasn’t stepped foot on the

mood since 1972

MERCURY

Mercury is the smallest planet in the Solar System at just 4,789 km

across its equatorThe temperature on Mercury ranges from

-183°c to 407°c

It is the 2nd densest planet. Each cm3

consists of 5.4g of metals and rock

VENUS

Commonly called Earth’s sister planet. Both planets are very

similar in size (638km difference in

diameter)

Venus is the 2nd brightest object in

the sky, visible on a clear day from Earth

It’s the hottest planet in the Solar System.

Average surface temperature is 462°c

EARTH

Earth is the most dense planet at 5.52g per cm3

Earth is the only planet to not be named after a

Roman God/Goddess

Due to the Earth’s rotation slowing down, each day on Earth is

0.00046575342 seconds longer than the last

MARS

Mars has the largest mountain in the Solar

System. Olympus Mons is a 21km high

and 600km wide volcano

It has the largest dust storms in the

Solar System. They can last up to 4

months and cover the entire planet!

Mars and Earth have approximately the same landmass

JUPITER

Jupiter is the largest planet in the Solar System at 317x the

size of Earth

The Red Storm has been on-going on Jupiter for 350+

years and is large enough for two

Earths to fit inside of!

Jupiter has a moon called (Ganymede) that is larger than

Mercury

SATURN

Saturn is the farthest planet

from Earth visible to the human eye

Saturn is the least dense planet. This

is due to being made up of mainly gas (hydrogen &

helium)

It is not the only planet to have

rings, but its rings are the most

prominent

URANUS

Uranus was the first planet

discovered using a telescope

The minimum atmospheric

temperature of Uranus is -224°C making it the

coldest planet in the solar system

The only spacecraft to visit Uranus is

Voyager 2 which passed in 1986

passing at a distance of 81,500 km

NEPTUNE

Neptune was the first planet to be predicted

by mathematical calculation, it was

then seen via telescope

Wind speed on Neptune can reach 1,500 mph (fastest

detected in the Solar System)

Neptune is the farthest planet from the sun. It takes 165 earth years to orbit

the sun

PLUTO

In 2006, Pluto was reclassified from a planet to a dwarf

planet

Pluto has an eccentric and inclined orbit. This means every so often, it is closer to the sun

that Neptune

Pluto was discovered in 1930 after being

predicted by changes in the orbits of Uranus

and Neptune