Space is vast and ever growing, and its peculiarity continues to fuel the field of Astronomy. Astronomy delves into the world of all extraterrestrial objects, space and the physical universe as a whole – a pretty big task. This month, we’re taking a look at our solar system and exploring what makes life on Earth possible.
Located in an outer spiral arm of the Milky Way galaxy, our solar system consists of our star – the Sun, and everything orbiting around it. This includes the planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune; dwarf planets such as Pluto; dozens of moons; and millions of asteroids, comets and meteoroids.
What Makes Earth Suitable for Life?
Distance of the Earth from the Sun
The distance of the Earth from the Sun creates perfect
conditions with the ideal amount of heat and light to
allow life to be created and supported.
Light on the Earth
Earth is the only planet that uses the Sun’s light as a source
of energy. Life on earth has evolved to harness sunlight via
photosynthesis, which as a by-product, releases oxygen.
The Earth’s Atmosphere
Our atmosphere consists of the exosphere, thermosphere, mesosphere, stratosphere and troposphere.
The air content and atmospheric pressure also promote life.
Compared to other planets, our atmosphere has less carbon dioxide than planets like Venus and Mars, which in turn helps moderate the Earth’s temperature.
The Ozone Layer
The Ozone layer is a part of Earth’s atmosphere situated in the stratosphere. It protects life on Earth from harmful effects of shorter wavelength and ultraviolet radiation (UVR) from the sun. Gases like chlorofluorocarbons in spray cans and refrigerants break down ozone molecules in the upper atmosphere, which has resulted in an ozone hole over Antarctica and much of New Zealand. As a result, UV exposure and rate of sunburn is much higher there.
Water
Water is essential for life, which is why so much of our interplanetary travel and research focuses on the search for fresh water.
The Earth’s Gravitational Pull
The Sun’s gravitational pull keeps our planet orbiting the Sun, and Earth itself in shape and form. The force of gravity doesn’t just keep us anchored to the ground, but also affects our biological system and development. Plants even use gravity to determine which way to grow (gravitropism).
Favourable Climatic Conditions
Our climate allows for life to flourish, and is the result of all the above factors working synergistically and cohesively. So, it’s safe to say that after a few billion years everything came together just right.
Memorise the Planets
My – Mercury
Very – Venus
Eager – Earth
Mother – Mars
Just – Jupiter
Served – Saturn
Us – Uranus
Nine – Neptune
Pizzas – Pluto
Did You Know?
- There are more stars in the universe than grains of sand on all the beaches on Earth. That’s at least a billion trillion!
- Black holes are created when big stars explode.
- The universe has no centre and is constantly expanding.
- The moon is the reason why we have tides and waves on Earth. Along with the sun, it moves billions of tonnes of water each day.
- Many of the atoms you’re made of, from the calcium in your bones to the iron in your blood, were brewed up in the heart of an exploding star billions of years ago.
- The sun makes up 99.86% of the mass of the solar system. It’s so big that you could squeeze 1.3 million Earths inside of it.
- The universe began with the Big Bang, and is estimated to be approximately 13.7 billion years old, plus or minus 130 million years.
Helpful Resources
solarsystem.nasa.gov – This website is NASA’s real-time science encyclopedia of deep space exploration. NASA’s scientists and hardworking robots are exploring the wild frontiers of our solar system, and bring as much information to you as possible to learn, explore and understand the vast universe.
www.natgeokids.com – National Geographic Kids is a fantastic interactive platform to discover facts about animals, science, history and geography, along with fun competitions, games and more.
www.space.com – On space.com, you can find the latest news about space exploration, innovation and astronomy. Here, we celebrate humanity’s ongoing expansion across the final frontier.
www.esa.int/kids – ESA Kids features space news, information, animations and downloads for kids aged between 6 and 12, making space more accessible for kids.
