Friday 29 July 2011

The greatest photograph ever taken by mankind?

Hello again! I know it has been a while, but life has been spectacularly hectic with geology  taking a back seat to my singing exploits. My other blog, A Nightingale Sang... will fill you in on exactly what's been going on if you are interested. Meanwhile, I recently acquired a copy of Professor Brian Cox's excellent book and DVD of his fabulous  TV series, 'Wonders of the Universe'. It's absolutely mind boggling stuff, non more so than the following photograph included in the book and taken by the Hubble telescope. I honestly think it ranks as the single greatest photograph taken by mankind.

A bold claim perhaps, but I believe the photograph that follows is exactly that. Take a look at this:-

The Hubble Ultra Deep Field
(Taken from hubblesite.org)

Okay, so on first glance it may not strike you as all that spectacular - just a photo of the night sky with lots of different coloured stars? Well yes, but take a closer look! Some seem to be more like fuzzy blobs and some almost disc-like in shape. Others seem to be linear features, almost like the trail of a comet.

In fact, nearly all the features in this photograph called the Hubble Ultra Deep Field, and taken by the Hubble telescope, are in fact not single stars, but galaxies. That's around ten thousand galaxies, each made up of hundreds of billions of stars. If that isn't mind-boggling enough, consider this. . . .

In 2004 it was decided to focus the Hubble telescope's gaze on a seemingly empty piece of space in the southern constellation of Fornax. A tiny piece of the night sky was chosen and the telescope trained on this location for a period of eleven days, spread over four months. Each of the 800 exposures lasted for around 20 minutes. To all intents and purposes, there was nothing there to see, but over this extended time period ancient, distant light may be received if left for long enough. The dimmest objects within this image are a result of the Hubble telescope receiving just one photon of light per minute. The result is this fascinating image of some of the most distant objects ever observed.

The really fascinating thing about this image is that when you look at it you are in effect travelling back in time. The lighter and larger galaxies visible with distinct spiral arms are a lot closer than the smaller redder ones and it is these tiny red ones that are the most intriguing. Astonishingly, it has been calculated that the oldest galaxy seen within this photo is over 13 billion light years away. Therefore, what we are seeing is an image of a galaxy a mere 600 million light years after the Big Bang and the beginning of the Universe itself!

Professor Cox's book is crammed with amazing, mind-numbing information and it's a really compelling read. It adds a great deal to the TV series and I would recommend reading it alongside the DVD - not simultaneously unless you want your brain to explode.

Go purchase and enjoy!

Cheers for now,
Alyn.

Sunday 20 February 2011

Volcanoes, Earthquakes and Tsunamis - a review of S186.

It always helps me to look back on what I have learned on completion of a Open University course, and I aim to take a look at a few key points from he last one - S186: Volcanoes, Earthquakes and Tsunamis. I'll make a start by looking at one misconception that I had held since my school days.

If you think about the prospect of great expanses of rock flowing like a river, one inevitably thinks of rock heated sufficiently below the surface to change it into a molten state. Thus, when a combination of circumstances allow it to erupt from a suitable opening at the surface a river of molten rock, or lava results.

One revelation produced by the course, was that the mantle was made up of solid rock, that circulates in a solid state - 'solid state convection' as it is known. Now just how can a solid lump of rock really circulate by convection? It defies logic surely? Generally speaking, a 'fluid' is anything that can 'flow', but in geologic terms it can include solids that when under specific conditions of pressure and temperature can also flow while maintaining their solid state.

Arthur Holmes, in his renowned book 'Principles of Physical Geology' explains the paradox of flowing solids wonderfully. He gives the example of pitch, which behaves like a brittle solid if struck with a hammer causing it to shatter, but under ordinary temperatures, will flatten out into a thin sheet simply under its own weight.

Another solid clearly seen to flow is ice.

Above: The Franz Josef glacier, New Zealand


At first sight, what may seem to be a static expanse of ice, rapidly (in geological terms) flows down the mountainside. The photo above, of the Franz Josef glacier almost looks like a river, complete with rapids!

As Arthur Holmes stresses, the key is time. Holmes illustrates this with the example of a ball bearing. If one is dropped into a jar of water it would take only a second to sink to the bottom. If the jar was filled with oil it would take several minutes. If filled with wax it would take maybe a hundred years to reach the bottom and if filled with ice and kept at a constant temperature, it would take millions of years.

So it is with rock. If pressure is maintained for long enough, rock will flow and bend and in the mantle it circulates. However, when rock rises, the pressure upon it decreases, causing partial melting and a change to liquid form. This of course leads to the formation of igneous rocks by way of extrusion at the surface through a suitable fracture to form extrusive rocks such as basalt, or  cooling slowly below the surface to form intrusive igneous rocks such as granite.

I will get stuck into the subject of igneous rocks and volcanoes next time.

Cheers,
Alyn.


Saturday 12 February 2011

Life's rich tapestry?

Sometimes, life never ceases to amaze at its power to excite, shock or bewilder. This week saw the truly shocking and heartbreaking as well as the beautiful and heartwarming.

Firstly, the weeks work started with the distressing news that a serious accident had occurred over the weekend, on the road construction site where I work. For reasons yet to be determined, a young, 24 year old lad had been caught between the bucket and tracks of a large digger, which crushed one of his his legs below the knee. Sadly, after repeated surgery, doctors were unable to save the leg and had to amputate.

Now, I'm of the opinion that work is a means of earning money to fund the rest of your life's activities. Some have the added benefit of gaining some sort of pleasure from their daily work while many more have to endure a high degree of tedium and drudgary, day in, day out, just to 'earn a crust'. But whatever one has to go through in order to earn a living, the least one can expect at the end of the days graft is to arrive home with a full compliment of limbs.

God knows how this poor guy is going to come to terms with his new life. Hopefully he will get the support he deserves from all around him, including his current employers. My thoughts have been with him for most of this week and also with the the unfortunate colleague whose actions unwittingly brought about this unfortunate incident. Heaven knows how he is feeling too and I'm sure he will need just as much support to get over the trauma. If our employers corporate aims and trendy slogans mean anything, they will both get it!


On a lighter note, the previous weekend saw the latest performance of 'Enchanted', the singing group of 'young ladies' including my eldest step-daughter Anna-Ruth. These gals are getting quite a reputation in the East Midlands and if you check out the You Tube videos highlighted in the right-hand column of this blog site, you'll see why! On Saturday they appeared in a concert with the Loughborough Male Voice Choir in Kegworth.

The girls were outstanding once again as were the 'lads' from the Male voice choir.  In the opinion of my wife and daughter, the choir could benefit from some younger blood and guess whose arm was twisted?  Yep, 'fraid so! Thursday evening saw me going along to their rehearsal which proved an interesting experience, not least because it was difficult to determine quite where my voice lies. 'Bass' or Baritone - that is the question! It was a fun evening I look forward to more next Thursday! Watch this space for developments!

Actually, this may well spawn a new blog! Better keep 'Holey Schist' a Geology/Natural History blog I think.

Next up will be a look back at 'Volcanoes, Earthquakes and Tsunamis', the OU course recently completed which threw up such interesting questions as 'when is a solid not a solid'! Answer to be revealed . .

Cheers for now,
Alyn.






Sunday 2 January 2011

Sir David Attenborough - a British broadcasting legend

The first draft of this post was intended to be a straight forward review of this year's 'Christmas Books' that Santa saw fit to send my way this festive season. Among the three that he bestowed upon me this year was 'First Life' by David Attenborough and Matt Kaplan. It is the book of the TV mini series of the same name and is a wonderful piece of work. But it got me thinking about the influence David Attenborough has had on my life and after giving it some thought I realised it has been enormous!

Born on 8th May 1926, David joined the BBC in 1952 and rather bizarrely, was initially discouraged from appearing on camera because it was thought that his teeth were too big! His first contribution to the subject of natural history was a three part BBC series called 'The Pattern of Animals' that he presented and produced himself.

My own first recollection of the man was when I started to watch the epic series 'Life on Earth', which brought the incredible variety and beauty of life on earth in all its glory. While Attenborough presented the programmes, it was the animals who were the real stars. One progrmme that I've never forgotten featured the Mountain Gorillas in Rwanda. The way the series introduced the ugly as well as the beautiful, the weird as well as the wonderful was pure genius and it set the standard for natural history broadcasting.



As well as presenting the regular series 'Wildlife on One', the 'Life' series continued with 'The Living Planet'.
This series built on the success of 'Life on Earth' and was based on ecology - the way in which animals adapt to their environment. This was another brilliant series and was followed by 'The Trials of Life' looking at animal behaviour. This  completed the 'Life' trilogy, which was the original intention, but other more specialist series covering all facets of life were to follow. In 1993 he presented 'Life in the Freezer', highlighting the natural history of Antarctica.






A noticeable omission from Attenborough's works up until this point was the world of plants and this was addressed in 'The Private Life of Plants' in 1995. The reason for the reluctance to devote too much air time to plants is that they are essentially immobile objects and tend not to do a great deal. How do you make an hours TV programme depicting unmoving objects and make it entertaining? Well, this problem was tackled brilliantly with the use of groundbreaking time-lapse photography to speed up growth, death and seed dispersal.

Following on from this came 'The Life of Birds' (1998); 'The Life of Mammals' (2002) and 'Life in the Undergrowth' (2005), To complete the story of 'life' 2008 saw the production of 'Life in Cold Blood', focusing on the remaining animal groups of amphibians and reptiles. And that was intended to be that until he realised one final, but major omission - the very beginning of Life on Earth. This thought spawned the ultimate prequel - 'First Life'. Another stunning piece of work, this time brought to 'life' by some magical computer animation.

What is a shame about this series and the superb book that goes with it is that for me, it came a year too late. It would've been invaluable in my recent study of fossils and the history of life with the OU! Nevertheless, reading it now is shedding more light on the mysterious onset of life and is helping me better understand the process of evolution. In fact this book ought to be required reading for the disappointing Darwin course that I've just finished. Or maybe the OU could ask Matt Kaplan to re-write the Darwin and Evolution course book?

Anyway, what fascinates me is the Ediacaran period and the discovery of a group of fossils in pre-cambrian rocks such as Charnia masoni, first discovered in April 1957 in Charnwood Forest by an eleven year old schoolboy called Roger Mason, who ironically attended the same Leicestershire grammar school as Mr Attenborough! What brings this subject to life is some superb animated computer graphics giving an interpretation of what these ancient lifeforms may have looked like all those millions of years ago. Of course no-one really knows what these creatures looked like or how they really lived, but isn't that the case with much of geology? It's all about evidence, interpretation, and the discussion that follows. In this book Attenborough offers all sides of the argument, such as in the pros and cons of the 'Snowball Earth' theory, but leaves it to the reader to make his or her own mind up, which is how it should be.

I really hope the man is eternal because BBC television without David Attenborough is quite unthinkable. Even though he's in his eighty-fifth year, I'm sure there will be a few more gems to come from this genius of broadcasting. Long live David Attenborough - a real 'national treasure' if ever there was one!

Cheers,
Alyn