Sounds of Science #04

Dark Energy

So most of our universe (over 70%) is made up of something called Dark Energy. We can't see it and we don't really know what it is...

Matter - everything that makes up me, you, planets and stars - appears to make up only a very small fraction of the universe, about 4%. Instead, the universe seems to be filled predominantly by a very strange material known as dark energy and it is this material, with it's anti-gravity properties, which seems to speeding up the expansion of our universe. We've known that the universe was expanding since Edwin Hubble made his observations in the 1920s, however it's only in the last 20 years that we've realised that this expansion is actually speeding up! The problem is that we can't directly detect dark energy and this makes it very difficult to understand what it is and whether it really does exist.

Instead we must rely on indirect observations, looking at light travelling from the far reaches of the universe to determine whether the properties of this light has changed during the time it has taken to reach us. A good way to measure the expanding universe is to make observations of distant supernovae (huge explosions which follow the death of large stars) which act as 'standard candles' or 'lighthouses' because we know how bright these object should be. Measuring light from distant supernovae has allowed us to see that it is different to what it should be if these objects were positioned within a static universe. Instead what we see is changes in this light which indicates that these objects are being flung outwards and away from us via some sort of cosmic expansion.

A nice analogy to describe the expansion of the universe is what happens when two points are drawn on the surface of an inflating balloon. As the balloon is inflated, the two points begin to move further and further away from each other and as the material expands outwards, the distance between the two points also increases. Applying this analogy to the cosmos, we could imagine the same happening with two galaxies being pulled apart from each other as the space they exist in expands.

As dark energy is so difficult to detect, scientists have recently been looking for new ways to independently verify its presence within the universe. Whilst at the BBC I was lucky enough to interview cosmologist Dr Chris Blake from Swinburne University, Australia who has recently published two papers reconfirming dark energy via a new set of methods. Blake and his colleagues produced a galaxy map of over 200,000 galaxies and used this information to look at how these galaxies were distributed and how they grew relative to each other. Through this work Blake and his colleagues were able to reconfirm the presence of dark energy and perhaps most importantly were able to determine some of its properties.

I thought I'd use the audio from this telephone interview and spruce it for the next sounds of science episode:

[soundcloud width="100%" height="81" params="" url="http://api.soundcloud.com/tracks/18436704"]

It probably sounds better with headphones (or obviously decent speakers).

Useful links:

http://www.bbc.co.uk/news/science-environment-13462926

 http://preposterousuniverse.com/writings/cosmologyprimer/faq.html#dmde

http://supernova.lbl.gov/PhysicsTodayArticle.pdf

Alder Hey's Dawn Chorus

Our response to sound and noise are influenced heavily by the psychological associations we have with them. Hospitals and their internal soundscapes obviously carry very negative connotations and in the case of young children these negative associations can lead to increased levels of distress and fear. However the reverse of this is also true, certain sounds can have very positive associations and the effect of listening to these sounds can be very positive and powerful.

Several weeks ago, I was walking down the central corridor of Liverpool’s Alder Hey children’s hospital when I became aware of the sound of birdsong. As I continued down I could hear quite clearly the sound of a single blackbird gracefully chirping through the din of the chaotic hospital. As I focused on the sound I found that it brought with it a sense of calm and I begun to lose the feeling of unease that I tend to experience inside hospitals. However, there was no sign of this little bird or any other wildlife inside the hospital, save from the colourful murals adorned across the corridor walls. I quickly realised that what I was listening to was a very special sound installation; playing out the wonderful recordings made by BAFTA award winning sound artist Chris Watson.

I’d come to Alder Hey specifically to talk with their Arts Coordinator Vicky Charnock to find out how the hospital had been experimenting with sound to improve the experiences of their young patients. I also got chance to speak with Chris Watson, the creative talent behind the installation and he explained to me why he chose to bring the sounds of a local park within the walls of this hospital.

The Dawn Chorus installation forms part of the larger Sonicstreams project which is a creative collaboration between Alder Hey and the Foundation for Arts and Creative Technology (FACT); the project aims to creatively explore the impact of sound on the human body.

You can listen/download the radio piece below:

[soundcloud width="100%" height="81" params="" url="http://api.soundcloud.com/tracks/12781881"]

Sounds of Science #03

EchoBank

In this Episode I visit Dr Kate Jones at the Zoological Society of London to find out about a bat call reference library they're developing called 'Echobank' which is being used in conjunction with the iBats monitoring program. Scientists at the Zoological Society of London are using Echobank to teach a neural network to identify specific bat species from the acoustic properties of their calls.

Although this may sound pretty niche, it's really cool stuff because the technology has much wider applications. Firstly the team are using it in combination with a smart phone app which can be used by anyone to take bat call recordings. In doing this the team hope to collect global distribution data for bat populations, which Dr Jones is hoping to use to determine whether bats can be used as a 'heart monitor' for the state of the environment. As bats represent one fifth of all mammalian species and exist in a huge range of habitats (from your local park to the tropics), changes in their global distribution could be used to monitor the impact of climate change on the natural world.

Secondly, the team are doing a lot of really important science engagement, working with ‘citizen science’ networks across Europe to gather data on bat populations. The team have been helping groups across Europe to develop and carry out their own monitoring programs, which feed data back to the iBats program. What’s great about this work is that it’s not only efficiently collecting distribution data, but also getting people interested in the state of their local environment. Standardisation is obviously an important factor when collecting data from multiple sources and with this in mind the team have developed the smartphone apps which can be used easily to take recordings and GPS data.

Finally (and what really excited me) was the suggestion that this ‘digital infrastructure’ could one day be adapted to identify any sound producing species from a recording taken on a smartphone. So imagine going out to your local park, taking a recording of a bird on your iPhone and getting probability results back on the identification of the species!

You can listen to the episode here:

[soundcloud width="100%" height="81" params="" url="http://api.soundcloud.com/tracks/11704888"]

Download it here

Or listen to the edited version as part of Short Science episode 89

Special thanks to Katie Draper who helped out with this episode!

Not bad for an old man... (Apollo 14)

Continuing the Apollo 14 coverage - I was inspired to create a short radio piece on the mission which was broadcast on our 'Science @ 1' show earlier today. Check it out: [soundcloud width="100%" height="81" params="" url="http://api.soundcloud.com/tracks/13521655"]

[Update 03/05/11]

This segment was included on Short Science_89

[youtube=http://www.youtube.com/watch?v=IhXsjENGrk0&feature=related]

"It looks like you’re about on the bottom step... and on the surface."

"Not bad for an old man."

- Mission Control referring to Alan Shepard as he first stepped out onto the moon's surface. At the age of 47, Shepard was the oldest man to ever walk on the moon.

Merry Science-mas

As we're all gearing up to Christmas I suppose it's time for a little festive cheer - I'm sure you're all familiar with the 'Night Before Christmas' poem, well here it is with a little science orientated revamp! The poem was written (thanks to Ben and Catherine!) and produced as part of my MSc course.

You can listen to it here (to download, right click 'Save target as')

The lovely voices you hear are thanks to (in order of appearance): Tosin, Alex, me, Ben, Chloe, Jack, Catherine and Camilla.

Merry Christmas!

-Ed