Friday 27 November 2015

LIGHT AND DARK MATTERS Part 2


The Rest of the Day

After the sunrise walk with Dr Lucy and a 2nd breakfast (the full English Monty) I had a gap several hours before the afternoon lecture and discovered through chatting with other group members that there were two free entry workshops taking place at 11am.  So I headed along to the first one, an exhibition space run by Oliver Lang on mobile photography.  This included a detailed look at water microbes subjected to a laserbeam of light under a microscope that were then projected onto a wall, making viewing easier.  Also within the space was a projected light beam appearing to split the visible light spectrum and a display of light and colour with polarising filters entitled 'In/Visibility' by Vinita Khanna. In all the effects of this mobile exhibition space were quite astounding.  Please follow my numerous orange hyperlinks if you wish to find out more about each subject, but remember to come back here!








Water microbes laser light projection

In/Visibility by Vinita Khanna
  I met and chatted with a visitor here too
that had to be the most appropriately dressed guy
for not only the event but also the weather! Sadly Antonio has
Since removed his photo which is a shame as he looked great!

A photo posted by Antonio Cabrera (@antonio_cabreraseville) on
Oliver Lang has since put up a short instagram video of the mobile space.

A short walk along the corridor and I found the Ultraviolet Art workshop with Labern & Lloyd of The Drawing Shed.  Inside there was a range of very old-fashioned typewriters fitted with UV ribbon and a number of people were seated getting creative with the typewriters, black light torches and UV pens. Obviously I had to have a go at this!  My result was I'm afraid very sparkly: 
Twinkle's contribution to the UV Art workshop

To one side of the typewriter area was a large blackboard covered with a variety of drawings and equations fronted by two men talking animatedly to those seated informally on leather cubes and bean bags.   What a great hangout!

This was a very cool area where Q&A and general discussions on light, dark matter, dark energy and the cosmos was taking place to a captive audience. I sat here whilst Toby Shannon from The Institute of Physics relayed his knowledge on light, debated why blue LEDs should win the Nobel Prize as we all got very heavy duty with the cosmology questions for the scientists and they in turn gave us answers on the concept of 'nothingness'.

It was in this room that I first noticed a subtle, sometimes sub-conscious thing happening when the organisers and speakers were talking.

One of many wall messages viewable
with a Black Light torch
 
Labern & Lloyd artwork display
This thing was very visual in it's subtlety and in fact Toby Shannon actually described it in the same manner that I have always imagined it to be, he stated:

Dark matter could be viewed as if it were a piece of foam, with all the bubbles holding the galaxies, stars etc and the foam itself being the tendrils of dark matter connecting everything around it.

Mind map! Shocking to discover you're on the same wavelength as someone with much more education behind them.

Although not part of the exhibition, I am including below a black and white picture of a piece of foam I have at home, the type used to transport say a hard drive in the mail (two pieces fitting together forming a rectangle).  For a sense of perspective, this object measures 1.375 x 5.5 x 12.375 inches.  I'll ask you to come back to this foam picture later on.

Piece of foam on my kitchen worktop
After the engaging discussions with the Institute of Physics scientists, I headed outside to grab some lunch and air near the Christmas market in front of the Tate and here sampled some hot non-alcoholic Gluhwein, which was just as tasty as the alcoholic version.   The sun was out dancing between racing clouds, lots of people were walking along the river, shopping in the market or huddling beside hot food counters.  Just before entering the Starr Auditorium for the afternoon event, I purchased a couple of books from the Tate shop as stocking fillers for Christmas.

Although the auditorium filled quickly, I was able to obtain a seat to the left with a clear view of the panel just 4 rows from the front.  Asif Khan opened the proceedings with a short quote from Tanizaki's 'In Praise of Shadows' essentially an essay written in the 1930s comparing light and darkness to contrast Western and Asian cultures.  A candle was lit on the panel table with the 'scent' of space, one of Katie Paterson's creations.



The panelists Catherine Heymans, Katie Paterson and Dr Marek Kukula each gave a brief resume of themselves and their field of work and study before taking questions from the audience.
As an artist Katie Paterson draws inspiration from light and visible matter around her, but is also intrigued by the visual expressions possible from the invisible such as dark matter and dark energy, because I also engage in art this was perfectly understood.  Dr Marek Kukula explained that we don't as yet fully understand dark matter but we create images of beauty to describe it, this may be the result of not yet having the words to describe it hence the artistic connection.

In 2012 Catherine Heymans and Van Waerbeke led an international team of astronomers that mapped the largest ever scale of dark matter to date.  The ongoing project is the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS). 

Catherine Heymans referred to this image of dark filaments in the Tate lecture,
this was when I mentally made my connection to the foam.
A computer simulation of dark matter filaments

This mental connection was further reinforced when Dr Marek Kukula talked about the image below

Webs of dark matter, from Dark Universe part of
the American Museum of Natural History's Hayden Planetarium show
Back to that foam...I've always struggled with understanding and visualising Einstein's Theory of Relativity and comfortingly, I learn't this week on the 100th anniversary of that theory, he too struggled to describe it!

To date my own view has been based on that piece of foam with the 'whole piece' existing in the same moment in time across all sides.  A person standing in one part of the foam sees an event say in the middle, another person on the other side sees the same event but possibly the event is seen to them at a different point in time due to disproportionate distance.  But..the event happens in one moment (a unit of time) and is then gone.  This is how I understand the phrase 'everything happening in the now' and why 'time' cannot go backwards, only forwards for everyone, no matter where they are in the universe.  In just a few minutes, the quantity of dark matter particles that pass through a fingernail is in the billions.  Think of how much then there is between you and the computer keyboard, the computer and your window, your window and the outside world.  It's almost like a never ending reflection in a mirror but instead of getting smaller, the particle quantity is growing.

Asif Khan showed the audience a relatively new substance in a round sealed plastic container able to conduct heat, block light particles and not reflect them.  The substance is called Vantablack and although I had heard of it, I had never seen it up close, something he gave us the opportunity to do after the talks. After asking the question, I was intrigued to discover the shape of the particles were like hexagonal nanotubes, neatly fitting together to form a shape so tightly packed that light cannot get through. Applications for this substance could be camera equipment and telescopes to name a few.  When drawing with graphic pens I've often been frustrated by not being able to achieve a complete black block of colour, maybe one day pens will be made of this stuff too!


The Panelists
By the time all the questions had been answered in the audience and the lecture was over, I was beginning to feel the effects of rising at 4.00am with very little sleep beforehand. 

Needing coffee badly I said goodbye to the people I had met along the way this day and headed for my car back through Borough Market to St Thomas's Street. 

Just before going underground to the car I caught sight of the Moon just escaping the clutches of The Shard.



All round this was a very entertaining day out and I really hope that Tate Modern do more of this collaboration with science again.

I hope this has given a small taste of Light and Dark Matters to the reader who might be encouraged to research further.

I make no apologies here for incorrectly theorising anything, that is the freedom of personal thought.  Where possible I have tried to link, embed and credit those involved with this wonderful day.

With the greatest thanks to Tate Modern and The Institute of Physics.




LIGHT AND DARK MATTERS Part 1

The Sunrise Walk

On Saturday 21 November 2015 I spent the day at London’s Tate Modern for a series of walks, talks, events and workshops staged as part of the International Year of Light.  The fact I made this event at all was due to seeing a tweet fly past on my timeline detailing the event a week earlier, but I’ll come back to that.
On 17 November I bagged the last ticket to take the 7.15 am sunrise walk with Dr Lucy Green of the Mullard Space Science Laboratory, UCL’s Department of Space.  In addition I booked the afternoon Tate session entitled ‘Are we darkened by light?’ with Catherine Heymans, Katie Paterson and Dr Marek Kukula chaired by Asif Khan.
In order for me to arrive on time for the sunrise walk I had to rise at 4.00am travelling in from Essex. The journey along the M11 in the clear twilight was uneventful until I reached the brow of the hill by North Weald airfield, where as always I was struck by the dancing array of lights from the skyscrapers of London on the far horizon.  Within 12 miles I knew I would be bathed in megawatts of light.

Having booked a parking spot near London Bridge, it was just a short walk through Borough Market and along Jubilee Walk on the Southbank to reach Tate Modern.  Seems quite early I guess but in fact I ended up with just minutes to spare after a series of spanners in the works including being woken up 3 times during the night, one of which involved disabling our home fire alarm at 3am and another on arrival in London when the entrance to my parking area was blocked by a fire incident truck.  All designed to throw me off kilter I guess but these are the reasons for time management and planning!
It was a bitterly cold morning with a persistent north wind blowing and although I was wrapped up, I had failed to check the wool beanie was inside my trusty flying jacket, so my head was resigned to exposure.  At first I couldn’t manage to raise anyone at the front entrance to the Tate, so I tried the staff entrance and within a minute Dr Lucy appeared in that reception accompanied by two helpers armed with a bag of headphones and receivers.  We then trooped round to the Turbine Hall entrance to wait for the other walkers.
Our first stop along the walk from Southbank was approx. 50 yards along the Millennium Bridge where in the biting wind Dr Lucy had hoped we would see the sunrise; however the UK weather had other plans.  Here Dr Lucy discussed our knowledge of the Sun, it’s dynamic internal convection process, the magnetic field and particularly the ability to recycle turning hydrogen into helium at the core with heavier elements such as carbon, oxygen, neon and iron being formed by stellar nucleosynthesis.  The Earth’s relationship with our Sun being that most of us and it have at some time been formed from these elements when the solar system was born and will continue to do so for another 5-7 billion years, when the Sun recycles again, becomes a red giant followed by a planetary nebula and finally a white dwarf.

A timeline of the Sun’s life (Credit: Smithsonian National Museum of Natural History and the Smithsonian Astrophysical Observatory)
The Evolution of the Sun is a fascinating subject for anyone wishing to explore further please use my orange hyperlinks in this blog, but remember to come back here!  
Our little group bravely moved on across Millennium Bridge to the framed view of St Paul’s Cathedral for the next stop where Dr Lucy discussed further the Sun’s magnetic field, it’s influence on Earth and the rest of the solar system and our first real understanding of that far-reaching process when space travel began in the 1950’s and 1960’s.  We were shown and able to hold a primitive early edition of a radiation detector used aboard aircraft and later developed for space travel.  Had we then not been interrupted by everything mother-nature could possibly throw at us including thick sideways blown blobs of snow, I might have had a nice picture of this object to include here.
We moved onwards towards the Bank of England, stopping just before under an arch by King Street.  Here we shook off the accumulated wet stuff and listened to Dr Lucy talk about the economic impacts of the Sun.  With the advent of electricity and technology in the 20th century the economic risk factors have increased.   When our nearest star decides to cough large quantities of matter and electromagnetic radiation out during the course of a CME or solar flare with the solar wind, it doesn’t just produce aurorae displays for our pleasure.  The subsequent shockwave of a CME or flare when it reaches the Earth causes our own magnetosphere to compress on the day side and stretch further out into space on the night side.  The magnetosphere works to protect us to some degree from solar storms, but there are other initially invisible reactions at work.
One such solar storm occurring on March 13, 1989 initially caused short wave radio interference with the arrival of x-rays and ultraviolet light ionizing the upper atmosphere, then aurorae recorded as far south as latitude 19° (Grand Cayman) followed by a total blackout for around 9 hours to the province of Quebec, Canada as a result of magnetic field changes giving rise to underground electrical currents that then interacted with the local igneous rock sending the current through power lines to ultra-sensitive transformers.  To avoid further damage to the transformers the grid was taken down.  The cost in damage to Hydro- Québec was circa C$10m with almost 10x that amount to end-users. Across the US within minutes of this solar storm there were over 200 power related network issues.  In space, satellites had electronic issues with some tumbling out of control for a while.  A further solar storm in August that year brought trading on the Toronto Stock market to a halt.  It is easy then to see the economic impact of a major solar storm.
On route to the next stop I discussed briefly with Dr Lucy the differences between now and 200 years ago when the world was not so reliant on the electricity grid for daily life and therefore the subject of solar storms and their impacts were not on the science discussion agenda.  A repeat of the famous Carrington Day event in 1859 would likely disrupt our modern technically built world to such a degree it could take a decade or more to recover from it.  This is why solar studies and monitoring of spaceweather events are so very important to prepare and minimise the risk to infrastructure on Earth.
We carried on walking through the unfailing cold wind towards Walbrook stopping briefly under an archway to listen to the sounds of the sun through our headsets.  I have heard this before but it’s always nice to reacquaint yourself with the unusual.  This video has a small clip at the end of the sounds.



Unfortunately our next stop was blocked at Walbrook Wharf river walk by a 58 minute estimated wait for the crane to finish unloading city waste onto a barge.  A detour was organised to take us across Southwark Bridge to The Globe on the Southbank, our final destination before returning to the Tate.  Here Dr Lucy spent a short while reciting a poem by Simon Barraclough inspired by the Sun and Shakespeare taken from his collection book Sunspots .  It was a very fitting end to our walk and her tweet is shown here on the left.

Detour of our group walking along Cousins Lane

I think we were all a little relieved to be back in the warm confines of the Tate Modern where we were led up to the 6th floor for a breakfast of tea, coffee, cake and fruit.  During the walk I had chatted with many others in the group including several artists and these informal chats continued over coffee.  As an amateur astronomer I take a great interest in our Sun and regularly observe sunspots and finer details of our nearest star using safe white light filters and a Hydrogen Alpha eyepiece.  I showed one of these images detailing a solar prominence to a lady artist who was interested and it is reproduced here.

Nice clear curling prominence feature on the Sun's West limb - 8 Oct 2015

My interest in the subject of light and dark extends further to the stars outside our solar system and I have been following one variable star in particular now for a year whilst it displayed increasing light curve variations in the form of a Nova, observing this through the iTelescope network and collecting data myself.  This week I have chosen to ‘adopt’ V5668 Sgr for a year via AAVSO.
I would like to pass a huge thank you to Dr Lucy Green for taking the time to travel into London so early, braving some pretty extreme weather conditions to talk us through one of the most fascinating objects in the Universe, an extremely enjoyable Saturday morning all round.  I’m always looking to learn from such events even with subjects I’m already aware of, there is always more to take on board.