The Importance of the Moon

Earth's natural satellite - the moonThe Moon is something many of us take for granted. It doesn’t really do that much, it just sits up their in space.

When someone talks about the Moon what springs to mind? Werewolves? Cheese? Wallace and Gromit?

Maybe you think of Apollo 11 in 1969 and Neil Armstrong and Buzz Aldrin setting foot on the Moon.

I watched a very interesting BBC documentary recently called Do We Really Need the Moon? It explored how important the Moon has been to the development of life on Earth, and how important it may become in the future of space travel.

The Moon is likely to have been critical to the creation of life on Earth. It is believed that the Moon was formed when another planet crashed into Earth. At this point, the Earth was an uninhabitable, unstable lava wasteland. The collision created millions of pieces of molten rock which were sent into orbit. The biggest of these chunks of liquid rock grouped together (thanks to our old friend gravity) to form a new structure. Eventually all the pieces either became a part of the Moon, joined onto the Earth, or were flung off into space.

This massive collision reset Earth’s chemistry. Over the next 7 million years, it is thought that the Earth cooled, and water vapour condensed to form oceans. Oceans which the Moon controlled. The water nearest the Moon is affected by its gravitational pull more. This means that water recedes in other areas, amassing in the part of the ocean that is closest to the Moon. This is what creates the tides we know today, the same tides that are thought to have helped to create life – around 4 billion years ago.

Moon's gravity pulling the Earth

A picture from the BBC documentary Do We Really Need the Moon? showing how the Moon’s gravity pulls the oceans of the world towards it – creating tides.

So the Moon helped to create life, but that’s not all, it also helps to maintain it. The distance the Moon is away from the Earth, means that the tides are not too extreme. If the Moon were 20 times close than it is today then the Moon’s gravity would be 400 times stronger than it is today. This would create a huge tidal surge that would completely submerge all major cities around the world. At night, London would be underwater, and then a few hours later the waters would recede and flood New York. Evolution would not be able to adapt to changes that happened this quickly, and life on Earth would not exist.

The Moon also protects us in another way. Here is an image of the nearside of the Moon – the side we always see.

The nearside of the MoonNow here is an image of the farside, also known as the dark side of the Moon.

The farside of the MoonNotice a difference?

The farside is covered in a mass of craters, whilst the nearside is largely unscathed. Every crater on the farside of the Moon is a potential impact that the Moon has prevented for the Earth. Imagine that all meteoroids in space are chunks of iron, and the Moon is a giant magnet. The Moon pulls a lot of this space debris towards it.

Inevitably some meteoroids will collide with Earth, however the Moon does a pretty good job of shielding our planet from a lot of dangerous impacts.

We are pretty lucky really, if the Moon were much closer, or bigger, we wouldn’t be able to survive. Likewise, if it didn’t exist, we wouldn’t be here in the first place.

So next time you see the Moon, spare a thought for how integral it is to life on Earth.

That’s Not It!

Enjoyed this article? Feeling like you want a bit more Moon stuff? Next week I continue to look at the Moon, this time from the perspective of space travel!

The Size of Space

I’m starting with a fact today; two actually.

FACT

According to astronomer Dr Peter Edwards, if our solar system was a grain of sand, then The Milky Way (our Galaxy) would be 1,000 times the size of Durham Cathedral.

Durham Cathedral from the South

Durham Cathedral

FACT

According to NASA there are hundreds of billions of galaxies in our universe.

Need a more visual representation of that? Well luckily for you, the American Museum of Natural History have spent quite a long time developing a digital universe.

Somewhat mind boggling, isn’t it. Dr Edwards doesn’t think the human mind is really built to understand the enormity of the universe. I think I probably agree with him.

In 2012 the Hubble Space Telescope zoomed in on a seemingly empty area of space. This area of space could be covered up with just a single grain of sand if you were looking at it from Earth. Astronomers didn’t think they would discover much, but if you have a super duper space telescope, why not see what it can find?

This is what that seemingly empty bit of space actually looked like when Hubble zoomed in.

A Hubble Space Telescope picture of millions of galaxy clustersEvery single speck of light you can see is a galaxy. Yes the 100 or so huge ones in the foreground, but also the millions in the background.

Each of those galaxies contains billions of stars. Yes many of them look insignificantly small, but they are very very far away. So the well used fact that there are more stars in the universe than there are grains of sand on Earth is actually true. In fact there are many billions more stars in space than there are grains of sand on the Earth. Each star is in solar systems filled with matter – from specs of dust to moons and planets.

The title of this article suggests that I will try to quantify the size of space. This isn’t really possible, so all we can currently do is describe its size relative to other things. If I had to use one word to describe space, I think it would have to be enormous.

A key question surrounding space is: is it infinite?

That is an existential question which I doubt we will ever know the answer to, but never the less it is still an interesting question, which is worth considering.

The theory that the universe is a sphere – like the Earth – is a popular one, and I can understand the logic in this, if you keep going, eventually the universe will loop you back around to where you started. But then my problem with this theory is we can go beyond the Earth. We can travel around the Earth, but space travel proves that we can move in 3 dimensions, straight and sideways on Earth and then upwards into space. If you got to the very edge of the universe, what would happen if you went upwards? If there isn’t an upwards, what is there?

New Scientist states that from all current data, it seems that the known universe has a diameter of about 93 billion light years. That’s pretty big, but by no means infinite. So if this estimate is correct – which is ridiculously unlikely – what comes after that? A big wall with a no entry sign? Just empty space? Another universe? Who knows…

That’s Your Lot

See you next week for the next in the series.

Space – A Series

Space. It’s a big old space.

Insert awesome picture of space to keep people interested. Check.

The Carina Nebula - Space

The Carina Nebula – Picture taken by The European Southern Observatory (ESO).

What happens here on Earth is insignificant in the universe. That doesn’t mean things that happen here are unimportant – far from it – but in reality, we are tiny. Nothing we have done or can do has much of an impact on the universe. Nothing that happens here on Earth affects the marvellous enormity, complexity and vastness of space.

Our lives, this entire planet, our solar system and even galaxy are tiny. Nobody really knows how tiny – relatively – because nobody knows how big the universe is. Or at least how big it is it a specific point in time – given its changing and expanding nature.

I really enjoy learning about space, so I have decided to write a series about space.

In this series I plan to cover some of space’s big topics; including:

  • How big (or indeed small) are we really?
  • Information on the International Space Station
  • Will humans ever live on other planets?
  • Black holes
  • The future of space exploration
  • How has our knowledge of space changed things on Earth?

Key Terms

There are a few terms I will be using a lot during the course of this series. To help keep us all on the same page, here is how I am going to define them.

Space
Everything everywhere! Anything that exists, exists in space. Space can be a completely empty vacuum or it can be full of matter, or waves such as light and sound. If there is something, or the potential for something to be there, it is space.

Matter
Stuff. Things made of atoms. Tangible objects. Not including electromagnetic waves; like light.

The Universe
The zone of activity in space which contains all known matter.

A Galaxy
A collection of billions of solar systems.

A Solar System
A collection of matter, orbiting a star. That matter includes planets and smaller structures like asteroids.

A Planet
A large body which orbits a star.

Next Week

I have already written next weeks post, so I can tell you with all certainty that I will be exploring the size of the universe. See you then.

Earth Hour 2014

This is going to be short and sweet, so please read it.

Earth Hour LogoLooking back through the archives, I was a little shocked to see that I had never posted about Earth Hour before. Earth what I hear you cry! If you were tuned in on Monday you would have seen my attention grabbing untitled post, which linked to the Earth Hour about us page.

Today I give you a challenge, join millions of people around the world in turning off your lights from 8.30pm to 9.30pm.

From 8.30 tonight, turn off all your non-essential lighting for one hour, to show your support for WWF’s Earth Hour. If you work at an airport, take heed of the non-essential bit and keep the runway lights on!

Big Ben Clock Tower, The Eiffel Tower and The Empire State Building with lights off for Earth Hour

Lights off around the world for Earth Hour.

There are all sorts of fantastic projects that now take place because of Earth Hour; an event that only started in 2007. Here are just a few of the great projects that you can sponsor:

  • Protect villagers in Bangladesh from tigers by installing solar lights
  • Support rangers who help to prevent poaching
  • Help bring power to remote villages
  • Fund corral reef protection awareness

Show your support tonight, be a hero. 🙂