Thursday, 29 March 2012

The Eiffel Tower

BFTF happened to be in Paris recently and had the opportunity to, very briefly, visit the Eiffel Tower.

Paris, or Blackpool? Difficult to tell at this distance.

Aside from the fact that it-is-very-big, a striking feature of the structure is its rather stylish brown paint job.

The Eiffel Tower

The detail and complexity of the structure really is very impressive.

Close up of the first level, showing the groovy detail in the ironwork

One interesting feature of the first level of the tower is that the names of 72 French scientists, engineers and other notable people. Perhaps unsurprisingly, given that French Women were not given the vote until 1944, there are no women named in the engravings. Which is a shame, as there were certainly women who deserved a place, such as Emilie du Chatelet (mathematician, physicist, and author) or Marie-Sophie Germain (mathematician, physicist, and philosopher).

Very close picture, showing engraved names

Standing underneath the tower gives an interesting view. . .

Looking up from the centre of the tower


Detail of pillar, viewed from centre of Tower


One surprising feature is that the supports are embedded in large concrete blocks. . .

One of the towers four legs

One of the towers four legs, up close and personal

Detail of pillar element embedded in conctrete

The text in the last picture says "forges et usines de pompey. FOULD-DUPONT Fournisseur. Des Fers De La Tour" and refers to the fact that the wrought iron steel that the tower is made of was prodcued at the Fould-Dupoont steelworks in Pompey, eastern France.

The founders of the steelworks at Pompey (Auguste Dupont, Mayer Dupont and Adolphe Dreyfus) had originally founded an iron works at nearby Ars-sur-Moselle but had moved their operation south to Pompey when Germany annexed the Moselle in 1871 (following the Franco-Prussian War)(1)



In 1982, Pompey faced job losses of some 2,300 out of 3,500 steelworkers. Protests included locking the president of Sacilor in his office, meeting in Paris at the foot of the Eiffel Tower and, incredibly, making the Tour de France go through the Pompey factory.(2)

Further cuts and job losses followed, resulting in the complete closure of the steelworks in 1986 - mirroring closures seen in the steel industries of other countries.

References:
(1) :The Emergence of Modern Business Enterprise in France 1800-2930, Michale Stephen Smith
(2) : The Politics of Steel : Western Europe and the Steel Industry in the Crisis years (1974-1984) Yves Many, Vincent Wright: ISBN : 978-3110105179

Image Sources
All images BFTF's own

Wednesday, 21 March 2012

Cafe Scientifique Calender of Events


Cafe Scientifique is a place where, "anyone can come to explore the latest ideas in science and technology. Meetings take place in cafes, bars, restaurants and even theatres, but always outside a traditional academic context."

All the talks are at 8pm on Monday nights and the venue is the Basement of the Lord Roberts Pub, Broad Street.

16th Apr : Cyril and Roxanne Bennis - Palestine - Hope and Olive Trees
The speakers have participated in the last two Olive Tree Campaigns in the Bethlehem area of Palestine. This planting programme supports farmers who are at risk of having their lands confiscated under Israeli military occupation policies. The discussion is based on their personal experiences and impressions of life under the Israeli Occupation and the daily struggle this creates for Palestinians attempting to live with some semblance of dignity and human rights. .

30th Apr : Exploring some myths on animal testing
Our visitor is a religious minister and a long standing member of committees which regulate testing on animals. He would not call himself an ethicist, but an informed contributor who seeks by his contribution to both further science and lessen animal suffering.

14th May : Prof Elizabeth Stokoe - The Systematics of Social Interaction
Everything we do in our daily lives is accomplished through social interaction. Actions like questions, offers, assessments, or compliments are organised in ways that have important implications for understanding everything from complaining about a neighbour and assessing a classroom task, to saying no to offers of help and flirting with a potential new partner. In this talk, Professor Stokoe will present findings about the systematics of social interaction from her own work, drawing on audio and video-recordings from settings including student tutorials, romantic dating, police interrogations, and neighbour dispute mediation. She will show how she has developed these findings into practical applications in the world of communication skills training.

21st May : Dr Ines Varela-Silva - Take good care of your past because it will determine your future
The Developmental Origins of Health and Disease hypothesis (DOHaD) points to the idea that the incidence of certain adult diseases (for example, type-2 diabetes, stroke, and heart disease) are linked to development before birth. This means that the health of the mothers and grandmothers while they were growing-up, impacts the health of their children and grandchildren, even when environmental conditions change. In this session I will present results from our research with the Maya in the Yucatan, Mexico and with Maya migrants to the USA in order to emphasise the importance of the prenatal months and the first years of postnatal life as fundamental factors to guarantee a healthy adulthood.

28th May : Terry Kee - Phosphorus and the chemistry of life and death
Details not currently available

For more info, visit the Notts Cafe Scientifique website : http://www.meetup.com/nottingham-culture-cafe-sci/

or email: cafenottingham@gmail.com





Sunday, 18 March 2012

Lecture : How do you get down from a Yak ?

Dr Mike Clifford presented a rather unusual talk at The University of Nottingham recently. Part of their series of Science Public lectures, the talk was entitled “How to Get Down from a Yak”

Dr Clifford is Associate Professor at the Faculty of Engineering and has research interests in appropriate technology, composites processing, dynamical systems, and fluid mixing. It was the first of these that was the focus of the talk, covering a number of projects that aimed to help communities in the developing world. Many of these projects were undertaken by students in collaboration with the Christian relief and development charity Tearfund and with Engineers without Borders.

Handily, descriptions of many of these projects can be found here.

It’s perhaps worth looking at one of the projects mentioned (not in the link above) in a little more detail.

In 2010, MEng student Ellie Griffiths spent time with innovative Indian stove maker Prakti where she first worked in collaboration with Prakti for her final year dissertation where she designed and built an improved cookstove. As part of this effort, she researched what aspects of a stove were important to the women who actually used them. The rather interesting results are shown below:

Stoves : What people want from them
Characteristic%
Efficiency20%
Longevity20%
Ease of Use15%
Cost13%
Time to Boil11%
Pan Compatibility6%
Ease of Lighting5%
CO2 emissions4%
Mass2%
Aesthetics2%
Size1%
Exterior Temp1%

The Prakti Stove - lookin' good !



It’s worth noting that there is a worldwide community of people and organisations involved in designing high efficiency stoves for the developing world. And also in championing similar innovative technologies. Incidentally, the Wikipedia page on stoves is also something of a revelation, and it worth a visit just to see the ornate stoves that were installed in French Palaces

Another, somewhat related project, resulted in a stove being developed for Eritrea. The development of this was helped by some Eritrean cleaners at Notts Uni who kindly put prototypes through their paces and provided feedback to the development team.

Dr Clifford emphasised that technology needs to be appropriate, mentioning Schumacher’s (not that one, this one) book “Small is Beautiful” as being a good starting point to understanding the concepts of “appropriate technology”. Dr Clifford also pondered on the fact that despite the best efforts of many charities to introduce new technologies to the developing world, the biggest success story has been the mobile phone - a technology that has had no charity backing but one that people in the developing world have quickly recognised as being something that can give them real benefits, ranging from the farmer who can find out about wholesale prices to the young entrepreneur who makes a living selling airtime.

He also suggested that the best kind of technology transfer involved person-to-person contact, for example, someone going from house to house and talking to individual families about their cookers, understanding their needs and then suggesting small, cheap changes that they can make to improve performance, such as installing a chimney to extract fumes that would otherwise cause eye irritation. But this kind of thing doesn’t play well with donors as what they would like is to be able to say that X number of nice shiny new cookers have been distributed to villagers in an area.

In response to a question asking why developing countries were not able to develop these kinds of technologies themselves, Dr Clifford suggested that Notts Uni was able to offer some value, such as the ability to perform computer modelling to simulate heat flow in an oven.

In terms of the benefits for the students, Dr Clifford hoped that the projects had taught the students to question their decisions when designing equipment, taking the example of a bread oven for Uganda that was designed to be assembled using hundreds of nuts and bolts (because labour was cheap) instead of being welded (as welding equipment was scarce)

On the other hand, he also pointed out that when people tell you what they want, it isn’t always what they really need. Again, the example was the bread oven which was designed, as requested, to make 300 loaves per day. Unfortunately, it was only after the oven was delivered that the people using the machine realised that they couldn’t make dough fast enough to feed the oven, so it could not be used at anything like full capacity unless the owners invested in some dough making machinery.

Literally buns in an oven!

In the last of a slightly worrying series of cautionary tales, Dr Clifford narrated a tale from Nepal, where indoor air pollution from cookers is a real problem. A charity working there installed chimneys and new stoves in a number of wooden roofed dwellings. For the first six months after installation everything seemed to be going well, with the women and children reporting much lower incidences of eye and chest irritation. But then all the roofs fell in - because the smoke that had been irritating the people had also being killing termites in the roof. With the smoke gone, the termites were free to eat away at the woodwork.

The moral of the story clearly being to watch out for unintended consequences.

Oh and one last point, Dr Clifford did provide an answer to the rather cryptic question in the title of the talk “How to Get Down from a Yak”.

The response is “You don’t, you get down from a duck”, which he then quickly followed up with a description of a project in Tajikistan to try and separate the very soft down that Yaks possess from the rought, stiff, guard hairs that covers it. This turned out to be quite a difficult gig and at the time of he the talk, was a problem that had not been satisfactorily solved, although you can see a video about the project here.

Yaks have soft down? Who'd have thunk it?



Saturday, 17 March 2012

Science in the Park 2012

"Science in the Park" was the title given to a a cracking event held at Wollaton Hall recently to mark National Science and Engineering Week.

Sponsored by Nottingham City Council, The University on Nottingham and the British Science Association it was a great opportunity to see some what kind of science and technology is under development in the Nottingham area.

Presentations and displays covered topics as diverse as the BloodhoundSSC, fascinating plants and solar spectroscopy.

NSB was able to spend a little time at the event and, although only able to see a fraction of what was on offer, was very impressed, as you can see below (organisers review here) :

Maggots
NSB had a chat with Dr Chris Terrell-Nield, an entomologist at Nottingham Trent University, who was demonstrating how maggots do not react to red light but will turn away from blue light (see image below, the maggots are leaving a trail because they have been dipped in ink!). Dr Terrell-Nield explained that this was because the range of light frequencies that they could see was shifted towards the blue end of the spectrum compared to humans (indeed, they can see ultra-violet light which is invisible to you and I).

NSB asked him what other work he was involved in and he described forensic science research that he was undertaking with a PhD student to assess the effect of nicotine on maggots.

NSB was a bit confused by this, thinking that you could probably tell a dead person was a smoker by the packet of Woodbines in their top pocket and the yellow fingernails. But it all became clear when Dr Terrell-Nield explained that nicotine is an insecticide and that its presence in a body slowed down the rate of maggot growth. If this was not accounted for, forensic scientists would reach an incorrect conclusion on the date of death (you can read more about this here).


MEV Missile
The East Midlands Centre for Automotive Training has a MEV Missile electric car on display. One of the most interesting cars you have never heard of, the Missile is build by MEV in Mansfield and is one of the latest in a long line of interesting vehicles from that local company. Checkout their Wikipedia entry for a summary of what they have been up to!)


Chemistry Demonstrations
Sons1-3 attended one of the Chemistry Demosntrations by Dr Samantha Tang which must have been good given No3 sons verdict: "That was wicked"

Road Surfaces
One of the demonstations involved showing how road surfaces need different different layers to do different jobs, with the role of bitumen being played, quite winningly, by chocolate spread!



Sugar
British Sugar were also at the event with a bunch of stuff about how Sugar Beet is processed into sugar. NSB asked them whether UK beet production would still be competitive against African Sugar Cane if the beet wasn't subsidised. The chap on the stand thought that it probably would due to the transport costs of African Cane sugar. NSB isn't so sure, but that is perhaps an agument for another day. .
The British Sugar website has a lot of information on beet production and processing and is worth checking out.


As mentioned before, there was a lot of other stuff on, but the above is all that NSB had time to see.

Don't worry if you missed the event, because something bigger and better is coming your way soon - May Fest on 19th May 2012

A full list of what went on at Science in the Park is shown below. I'm sure that, like me, your gob will be well and truly smacked:

Yard Studio
Bloodhound SSC presentations
Chemistry demonstrations
Sound lecture

Yard Studio
Bugs, Bubbles and Bio-Fuels: How do microscopic bugs breakdown plant matter and produce bublles to make bio-fuel for our buses?
What's inside plants?: Activities showing how we learn about plants.
Solar System Model: Walk around models of the Sun and Inner planets in the garden and find out about the Nottingham Solar System Model.
The Solar Spark: Learn how to make hand batteries, a Newton wheel and a spectroscope; also have a go with solar toys
3D Terresttrial laser scanning: Experience laser scanning.
OPAL: Explore nature and view invertebrates with Open Air Laboratories.
Strawberry DNA Extract DNA.Learn how it is stored in cells.
What's in blood: What is blood made up of?

The Salon
Balloon Car Challenge: Build and test a baloon car.
The need for embryo biopsy: Have a go on a mock biopsy machine
Taste genetics:Find out if you are one of the 25% who can't taste PTC.
Human Body Project: Where are your vital organs?
Insect Gallery: Explore the world of invertebrates.
Geology Gallery: Seismology display with the British Geological Survey.

Willoughby Room
British Science Association: Get involved !
Physics Busking: Tricks with Physics with the IoP
Who can shout the loudest: Get noisy and get it measured.

Yard Gallery
RC model aircraft: Planes and a simulator from the Langar Model Aircraft Club.
British Sugar: The journey from beet to your homes.
Follow that maggot: Create abstract art with maggots
Gizmos Laboratories: Make slim, snow, cloud and even candy floss!
Road Construction: Construct Roads with rice crispies, chocolate, water and the engineers from URS.
South Nottingham College: An electric car and the STEM team.


Thursday, 15 March 2012

Talk by Peter Watkins about the LHC


Peter Watkins (Professor in the particle physics group at Birmingham University) presented a fascinating talk entitled “Searching for Particles at the Large Hadron Collider(LHC) at CERN” at a recent Café Scientifique event.

A very engaging speaker, Peter did a great job of explaining the subject.

He began his talk by explaining what matter is made of, pointing out that everything you see around you is made of atoms, that atoms are composed of a nucleus surrounded by electrons and that the nucleus is composed of neutrons and protons.

So far, so GCSE - but then Prof Watkins dug down deeper and explained that neutrons and protons are made of “Up” and “Down” quarks, which are the basic building blocks of matter and can’t be broken down any further.

As well as the quarks there are also ghostly particles called neutrinos which, because they have no charge, barely interact with matter at all. Millions of them are constantly passing straight through the earth without being hindered in the slightest.

So, we have four basic elementary particles : the Electron, the Neutrino, the “Up” quark and the “down quark.

However, in the heat of the very early universe, heavier versions of these particles were able to exist and these conditions can be recreated in facilities like the LHC.

The mass of particles is usually expressed as the amount of energy required to create them, measured in millions of electron volts(MeV). To give a feel for how much energy is in a MeV, a few calculations show that it is the same energy as grain of sand has after falling 2mm.

As well as these “building block” particles, there are also “force carrier” particles. Perhaps unsurprisingly, these carry the forces that hold the natural world together. The Strong and Weak Nuclear forces work within the nucleus of atoms, whilst Gravity and the Electromagnetic forces can work at very long ranges.

Peter commented on the strange fact that, at an atomic level, the electromagnetic force is 10e40 (i.e. 1 followed by 40 zeros) times stronger than the gravity force. That is a very big difference and there is speculation that this might be due to the gravity force leaking out to other dimensions.

As Neil Pye might say - “That’s pretty heavy, man!”

This seemingly bonkers notion has some support because Super String theory, a concept that aims to connect all the forces into one mathematical framework, requires 10 dimensions to work.

So, these elementary particles. How to describe them without it being confusing?

Tricky.

But lets have a go by summarising them in three tables. . .

Leptons : Cheeky particles that whizz about all by themselves
ParticleMass(MeV)ChargeDiscovered
ELECTRON0.5-11897
Muon105  -11936
Tau1776  -11975
ELECTRON NEUTRINO~0.001956
Muon Neutrinobelow 0.201962
Tau Neutrinobelow 15.502000
Note that only the Electron and the Electron Neutrino exist under normal circumstances. Also, the mass of the Electron Neutrino is not zero, but below a few millionths of a MeV

Lightning is a (very large) flow of electrons

Quarks : Needy particles that join together to form larger things like Protons or Neutrons.
ParticleMass(MeV)ChargeDiscovered
DOWN~6-1/31968
Strange~100-1/31964
Bottom~4200-1/31977
UP~3+2/31968
Charm~1290+2/31974
Top~173000+2/31995
Note that only the Down and Up exist under normal cirrcumstances

Murray Gell-Mann, together with George Zweig proposed the existence of Quarks.
For a laugh, Gell-Mann would sometimes pretend to be Sid James at parties

Force Carriers : Spooky particles that, weirdly, carry the forces we see around us
ParticleMass(MeV)ForceDiscovered
Photon0Electromagnetic1905
Gluon0Strong Nuclear1979
Z and W bosons~80000Weak Nuclear1983
Graviton?Gravitynot yet
Higgs~125000Mass?not yet
Note that light rays are Photons and that the discovery date of 1905 refers to Einstein's description of light as being packaged in "quanta" (now called photons)

Sir Peter Higgs, who predicted the existence of the Higgs Boson,
pictured here demonstrating his knowledge of all the STEPS dance moves.

Finding out whether there is a Higgs Boson - and what its mass is - is one of the aims of the LHC. Thus far, they know that, if it exists, its mass is somewhere in the range 110-150MeV as previous experiments have ruled out the possibility of masses outside this range.

The LHC
Starting at the beginning, it is perhaps worth mentioning that the “Hadron” in “Large Hadron Collider” is a name given to entities, like protons and neutrons, that are made up from quarks. Given that neutrons are neutral and therefore a tad tricky to accelerate using electromagnetic fields, it probably didn’t take the LHC team too long to realise that they were better off focussing on using protons as the particle that they would accelerate around the famous 8km diameter underground ring.

Now, whilst the LHC gets a lot of press coverage, to a layperson, it’s portrayal in the media seem to raise more questions than answers.

One question that had been troubling NSB was that surely, if you have two beams of particles going round a tube, they can’t get more than half way round without hitting each other!

Prof Watkins explained that the two beams are in separate, parallel tubes that intersect at four points around the CERN ring. At each of these locations is a different detector ATLAS, CMS, ALICE, LHCb

He also described how the protons were in bunches a few centimetres long and a about 100th of a millimetre in diameter. Each “bunch” contains about a million million protons and there are a number of these bunches circulating at any one time. In fact, bunches collide at the centre of the ATLAS every 25 nanoseconds. Of course, only a few of the protons from each bunch actually collide and the detectors record about 100 collisions per second.

Clearly, the LHC is a pretty technical piece of kit - but just how technical only became apparent when Prof Wilkins recalled the calibration process for the LHC’s predecessor the LEP (which used the same circular tunnel as the LHC). As the calibration went on, the operators noticed a recurring daily variability. After some headscratching, they eventually worked out that this was due to the tidal movements of the earth, which cause the diameter of the globe to oscillate by some 15cm every day.

Having accounted for this in their calculations, they carried on with their calibration process and found that there was some other effect that was subtly affecting the performance of the beams. This time it took a lot of headscratching, but after much drawing of diagrams and checking of possibilities, it was found that the problems were being caused by current leaking from the TGV trains on the surface and affecting the magnets around the ring deep underground.

Which leaves one with the curious vision of CERN staff arranging their experiments so that they do not co-incide with the 11.27 from Paris!


The ATLAS Detector
Prof Watkins spent some time explaining the workings of the ATLAS detector with the first point being that IT IS VERY BIG. You can get an idea of just how big when you see how tiny the people are in the drawing below.

Dear CERN,
Re: Funding for new CERN detector.
You have GOT to be kidding.
Regards
The EU

A larger version of this image can be found here.

Happily for you, gentle reader, NSB does not need to try and relate the detail of Prof Watkins very interesting explanation of the ATLAS detector, and can instead point you towards the rather groovy explantatory slideshows at CERN (see here and here).

The CERN site is a real goldmine of information, and gives a feel for the technical challenge faced by ATLAS as it describes how ATLAS has to filter out the interesting collision events from the routine ones

“When protons collide, some events are "interesting" and may tell us about exciting new particles or forces, whereas many others are "ordinary" collisions (often called "background"). The ratio of their relative rates is about 1 interesting event for 10 million background events. One of our key needs is to separate the interesting events from the ordinary ones."

"Furthermore the information must be sufficiently detailed and precise to allow eventual recognition of certain "events" that may only occur at the rate of one in one million-million collisions, a very small fraction of the recorded events, which are a very small fraction of all events. The term "event" here denotes a single proton-proton collision that may lead to an interesting configuration of outgoing particles."

The site also gives a feel for the scale of the computing challenge faced by ATLAS when it points out that:

“If all the data from ATLAS would be recorded, this would fill 100,000 CDs per second. This would create a stack of CDs 450 feet high every second, which would reach to the moon and back twice each year. . . . ATLAS actually only records a fraction of the data (those that may show signs of new physics) and that rate is equivalent to 27 CDs per minute.”

---------------------------------

Notes : Peter Watkins was part of one of the teams that discovered the W and Z bosons in the 1980s and has written a book about that exciting time. The book is called Story of the W and Z and is available from Amazon.


Image Sources :ATLAS , BubbleChamber, Murray Gel-Mann, Lightning, Peter Higgs


Sunday, 11 March 2012

Colours in Nature

NSB was at Rushcliffe Country Park today with Sons1-3 to take advantage of the glorious weather. In particular, the beautiful, clear blue sky rather touched NSB's heart and left NSB wondering what other objects in nature had such clear colours and whether this might make an interesting art meets science kind of post. . . .





Sky over Rushcliffe Country Park - March 2012


Full Fat Milk from ASDA - March 2012

Apple Juice from ASDA (just the ordinary stuff, times are hard and all that)- March 2012


NSB thinks that there might be a jumbo tomato, some orange juice and maybe a little mud in its future !

Notes:
Picures are all taken with a simple Nikon CoolPix L23 camera and are not messed about with in any way other than being cropped.

Saturday, 10 March 2012

Notts Uni May Fest 2012

Nottingham University's 2012 Mayfest was a great event for all the family.

Children could enjoy all the interactive demonstrationsevent while the grown ups could try and catch the researchers out with some trick questions - and both could marvel at some of the leading edge research being undertaken at the University.

To pick on just a few of the highlights of this years event ....

Researching alternatives to fossil fuels is understandably a very hot topic and teams were on hand to show what direction they were taking to develop better storage solutions for Hydrogen, better fuel cells, improved bio-fuel processes and much more.

A Fuel Cell powered car


A researcher explains how solar power works


Poster on some Hydrogen storage technologies being investigated


But if that isn't your cup of tea, how do you fancy checking out the canines on a sabre tooth tiger skull?

A Sabre-tooth Tiger skull


No university open day can be complete without an appearance by some liquid nitrogen and the shattering of fruits etc that have been frozen very solid by being immersed in its cryogenic depths.

Sir, can you confirm that this is indeed a Kiwi fruit?



Liquid Nitrogen - the crowd pleaser.



Mayfest spans the entire Universtiy Park Campus, and included tours of some of the "eco-homes" on the site. These are used in collaboration wit industrial partners to assess and trial various energy saving technologie, such as shared power generation and high lvels of insulation.
Two eco-homes investigating different energy saving technologies



Radio controlled cars and 'copters were also on hand to amaze and impress the young ones.

RC cars and copters -    cool!


And there was a Segway, which had a very long queue of children wanting to have a go...

The Segway- how DOES it stay up?


The Physics Buskers were had a series of engaging short experiments, including one in which showed that a balloon could be pierced, without popping, by a skewer....so long as it went through the top and bottom of the balloon, which are relatively thick and so less likely to stretch and tear.

With careful positioning, you can pierce a balloon !


Another cool demonstration showed how a simple mix of cornflower and water can make funky patterns on a loudspeaker

A mix of cornflour and water will dance if you play some fat tunes!

The History Department was showing some wonderful old documents, as well as the technology they were using to digitize them for posterity

Old documents on display...


...and discharged


oh my goodness, there's a Raspberry Pi !!

OMG ! A Raspberry Pi !!!


Lastly (although there was much else of offer that NSB didn't get a chance to look around), the School of Economics were playing various financial games with the visitors to show how certain principles worked.

A researcher plays a financial game with a visitor

Poster on the Tradegy of the Commons

A great event, NSB is already looking forward to the next Mayfest on 18th May 2013
Mayfest was a well-attended event

Looking forward to the next Mayfest on 18th May 2013

Why not atttend the 2013 May Fest on 18th May (see here) You can read a review of the 2011 event here and see pictures here.


Remarkable Solar Transit Image

This raises all sorts of questions. . . .

Monday, 5 March 2012

Interview : Prof Alfonso Aragón-Salamanca

NSB was hugely chuffed to have the opportunity to interview Alfonso Aragón-Salamanca recently. As Professor of Astronomy at the University of Nottingham, Alfonso certainly knows his astronomical onions and it was great to able to take advantage of his expertise to learn a little more about how the Universe works.

The interview covered topics as diverse as galaxy formation; what makes a good physicist; and the British sense of humour.

All the very best bits have been transcribed for you below. Enjoy!


NSB : To start with, could you tell us a little about how you got an interest in astronomy.

Alfonso : I was always very interested in science, I was good at science and maths at school. To be honest, I always liked any science, finding out new things. I think I could just as easily have been a biologist or a geologist or chemist - finding out things that people don’t know.

I ended up doing astronomy because I was good at physics and had a very good physics teacher and I started doing a degree in Physics in Madrid, back in Spain and then out of the options that I could take in physics, astronomy sounded quite exciting. From there I graduated and got the opportunity of doing a Phd in Astronomy at Durham in 1988. After that I worked in Durham for a while and then I moved to Cambridge and worked there for five years. Then, back in 1999, the Department of Physics at the University of Nottingham decided to expand into astronomy and hired five of us that formed the group which has been going ever since. . . Now the group is of the order of 35-40 people. We have been very successful, very good at attracting both students and researchers and from being a completely new group we are now one of the strongest groups in the country in our field of research which is extra-galactic astronomy.

The University of Nottingham has some buildings that Prince Charles would approve of . . .

. . . and some that he probably wouldn’t

NSB: Regarding the funding for astronomy, where there is no immediate application, where do you get the funding for your research and so on?

Alfonso : The teaching comes as part of the funding for teaching of science and physics. This has traditionally come mostly from the Government but is coming more and more from the student fees. For the research side, it is mostly public money through the Governments and European research councils and the Royal Society for “blue sky science”, science that doesn’t have any immediate application but you have to remember that two centuries ago, electricity was blue sky science with no practical applications. We have to write grant applications and compete with other universities for this funding. Governments also fund the equipment that we use, such as the Hubble telescope and the observatories in places such as Chile, Hawaii and the Canary Islands. We compete with other universities for the time on these telescopes.

It’s mostly taxpayer money, for which I’m very grateful that people realise that learning where we live and what the universe is like is important enough to spend reasonably large amounts on.
Faradays disc electric generator of 1831. Blue sky research of its day.

NSB : Does the technology that is developed for astronomy result in any spin-offs that do have commercial applications

Alfonso : Certainly, everybody now carries a phone in their pockets that has got a camera which uses a detector called a CCD - those detectors were developed partly for astronomy. In the 80s those detectors were very small, very expensive and one detector would cost hundreds of thousands of pounds. Now they cost only a few pounds, you carry them in your pocket and you don’t think about them. And space technology, communications technology, data processing technology - it all relates to sciences like astronomy.
A 2.1MP CCD from a digital camera. 2.1MP? That’s so yesterday. . .. 


NSB : The universe is a very big place, could you give some idea of just how big it is?

Alfonso : Probably the best thing to do is to start with something that we know about, such as the Moon. We can talk about distances by thinking about the fastest thing we know about - light, which travels at 300,000km/sec. It takes about 1 second for the light from the Moon to reach us and about 8 minutes for light to reach us from the Sun.

Moving to the scale of the solar system, it takes light about 8hrs to get from the Sun to the furthest planet, Neptune, and a few light months to reach the farthest reaches of the solar system where comets are in the Oort cloud.

Now, if we wish to get to the nearest star, that is 4 light years away.

The next big thing out there is our own Milky Way, our own galaxy that contains hundreds of billions of stars. This is perhaps a hundred thousand light years in size.

But we haven’t really started yet because there are about 100 billion galaxies in the universe. If we go to our nearest galaxy, the Magellanic Clouds, which we can only see from the Southern Hemisphere, these are 200,000 light years away and the nearest galaxy which is comparable to our own is the Andromeda galaxy which is about 2.5 million light years away.

And if we go the most distant galaxies that we can observe we starting getting to about 10 billion light years.

And the furthest we can see is the distance that light has travelled since the beginning of the Universe and that is about 13-14 billion light years.
The Universe.IS.VERY.BIG 


NSB: One thing I hadn’t realised is that the Magellanic Clouds were so close, that’s almost touching distance really !

Alfonso : In many ways they are, in fact touching. There is something called the Magellanic Stream which is material that is pulled from the Magellanic Cloud by our own galaxy and eventually, the Magellanic cloud will merge with our own galaxy.

NSB : When you take these pictures of very distant galaxies, why isn’t there something in the way? How do you get these clear lines of sight to such distant objects?

Alfonso: That is a very good question! The first thing you have to realise is that space is mostly empty and it is true that there is gas and dust in the way and in some directions there is more than in others. If we look towards the centre of our own galaxy we find it very hard to see because there is lots of gas and dust, which for astronomers means particles that are like soot. But if we look away from the plane of our own galaxy then the amount of dust that we see is very small and because space is largely empty, light can travel unimpeded from pretty much the beginning of the universe.

Different types of light travel better than others. We know that visible light travels through dust much worse than longer wavelengths such as infra-red and radio can get through pretty much anything

NSB : Could you tell us a little about the Lockman Hole, which may be related to this issue.

Alfonso : The Lockman hole is a direction away from the plane of our galaxy where the amount of gas is quite small. It is a very transparent window, as it were. It was discovered first when people were looking in X-rays, which have got quite a lot of difficulty travelling through dust and gas and they found a region [of the sky] where the amount of dust was quite small and they could point their X-ray telescopes and see lots of galaxies. Because there had been quite a lot of studies of galaxies in this direction, initiated by X-ray telescopes, other telescopes followed the same direction. In fact, the famous image of many distant galaxies was taken in the Infra-red. They could have done this study in any direction, but they pointed towards the Lockman Hole because of the information that was already available about the galaxies there.
Herschel Space Telescope image of the Lockman Hole.
Many of the points of light are galaxies, each with  hundreds of billions of stars.
Bonkers, isn’t it?


NSB : When you are looking at a star or a galaxy, how do you know how far away it is.

Alfonso : This is the most difficult thing in astronomy. We can measure the distance to the Moon and to the nearest stars using a technique called parallax where you look at the object from two different locations. So if I looked at the Moon from Britain and from Australia I would see that the apparent position of the moon is slightly different. The easiest way to demonstrate this is to hold a finger out in front of you and look at it with one eye covered and then with the other eye covered - the finger seems to jump from one place to another. That jump or change in position depends on how far away it is and you can do some very simple trigonometry to calculate the distance to the object.
To the nearest stars we observe them in June, say, and then in December. And in that time the nearest stars appear to change their position by a tiny amount, perhaps a 60th of a 60th of a degree. We can only do this for a relatively small number of nearby stars and we can do it better and better from space, we have telescopes out there like the Gaia mission which will be measuring the distance to billions of stars using exactly this technique.

NSB :So up to what distance, how many light years, can this technique work to?

Alfonso : Well, if you do it from the ground you can only maybe a 100 light years away, give or take. But from space, using very sophisticated measurements where you look at things time and time again and measuring the positions very accurately, you can make the technique for a fair fraction of the galaxy, thousands of light years. And this is very recent, we have only been able to do this from space for maybe the last 10-15years.

So that covers quite a lot of the stars in our galaxy - but it doesn’t get us anywhere near the end of the universe and this is where is gets harder and more uncertain.

When you measure the distances to certain stars using parallax you find the some of them, such as Cephids, change their brightness in a very peculiar way that we can recognise and is related to how bright they are. And if you know how bright something really is and how bright it looks, you can work out how far away it is. This is because moving something twice as far away, make it four times dimmer. People have been able to see Cephids all the way to other galaxies.

A particularly useful object is a type of supernova which, for reasons we don’t completely understand, is always of approximately the same brightness. They are extremely bright, which means we can see them very far away, up to half way to the edge of the universe. Again, as we know how bright they are, and we can see how bright they appear, we can then work out how far away they are. These supernovas have been used to measure how large the universe is and how fast it is expanding. We call these kinds of objects “standard candles” which means they always shine with approximately the same brightness.

(NB: An interesting article on techniques to measure astronomical distances can be found here)
Tycho's Nova, the remnant of a Type Ia supernova - an (admittedly very large) standard candle


NSB: Galaxies are often spinning structures. Why is this? Why aren’t they just big balls of stars?

Alfonso : Well some galaxies are just big balls of stars, these are galaxies called elliptical galaxies which can be round, rugby ball shaped or more elongated.

But a large number of galaxies look like they are spinning, they are spiral galaxies. And we can show they are spinning by using Doppler effect to measure the speed of the spiral arms that are moving towards us compared to the arms that are moving away from us.

We have an approximate answer to why they rotate but galaxy formation is still an evolving science. What you have to realise is that if something very large is rotating very slowly and then becomes smaller it will spin faster. This is well known law of physics called the conservation of angular momentum, which sounds very complicated but is like when an ice skater who is spinning slowly with their arms outstretched pulls their arms in and spins much faster. When galaxies form out of large clouds of gas, even if there is only a small rotation at the start, it will increase as the galaxy collapses.

So now the questions is why is there some rotation at the beginning. Galaxies do not form in isolation, they interact with other galaxies and gas clouds that are nearby, some may be moving past, some may fall into each other, perhaps at an angle, and merge. A galaxy could orbit a cloud of gas and, through the effect of gravity, cause a small amount of spin in the gas cloud. And these small rotations increases as the gas cloud then collapses.

NSB : Moving on to your area of research, how do the galaxies in the very early universe compare to those we see today.

Alfonso : The galaxies in the very early universe are younger in several ways, they have more dust and gas - and this is the raw material to form stars. And we do see them forming more stars, much faster, than nearby galaxies. They tend to be more irregular they haven’t had time to form regular shapes.

NSB : Just thinking of any youngsters out there who are considering studying physics - do you have any tips that you have found useful in your studies that you can pass on?

Alfonso: The first thing is that you must like it. Physics is not a subject you can study thinking that “ok I am going to get a good job at the end of it” because if you do not really like it you will struggle and you will not do well. The raw materials you need would be to be able to do maths reasonably well. When you study physics you will find that it is full of equations, it’s impossible to remember all those formulae. What you need to do is to think about the concepts and figure things out. Get the basics right. I can’t remember most of the formulae that I use in my work, but I can derive them if I understand the principles. So you need an analytical mind, not be scared of maths and to try to derive things logically instead of memorising everything.

NSB : Can you give a little bit of a flavour for the kind of careers that the students on your course end up in?

Alfonso : There is quite a range. We are very fortunate that physics is a subject that leads to many careers. Some of them become physicists and researchers, both in an academic environment and in technology companies. Some go into financial modelling or engineering. They are very numerate so they find careers in finance, computing, maths.The main thing a physicist learns is to solve problems to which you don’t know the answer. That is the key issue.
Physicists could end up at CERN working on this baby here, the ATLAS detector at the LHC. . .

. . . or they could end up at the Gherkin. .  .


NSB : It’s perhaps worth mentioning that many of the advances in computer technology, such as chip design, have been driven by a better understanding of the physics of how these materials operate.

Alfonso : Certainly, and here in Nottingham the department has a very strong tradition in solid state physics and semiconductor physics, developing new semiconductor techniques. For instance, if you come to the physics building there is a company called E2V who develop electronics like the CCD’s that we talked about earlier. They share our building and we collaborate with them.

NSB: The show talked to chemist Deborah Kays recently, who has a great love for the element Boron, she just likes that element, and I wondered whether there were any stellar objects that you had a particular fondness for.

Alfonso : There is a class of objects called galaxy clusters that I like because I can see the interactions between them, sometimes they collide and sometimes the properties of the galaxies change because they are living in these clusters.

Also, a particular type of galaxy called a lenticular galaxies, which are galaxies that are transforming from forming lots of stars to not forming many stars. The process that switches off that star formation fascinates me. I have put quite a bit of effort, and that of my PhD students to answer that question and we have made quite good progress.

NSB : Can you give some information on how ordinary members of the public can get involved and find out more about the research that is going on at the University.

Alfonso : Well, we have an active series of public lectures to which everybody is welcome. People can visit our website to find out what is happening at the department. The University also has open days twice a year where people are welcome to visit, either because they are interested in studying physics or because their children may be.

We also have a large outreach programme in which, for example, there is an inflatable planetarium that we take to schools. So it any listeners are thinking that they would like this to visit their school the please get in touch! We would be delighted, it is part of our job, we want to bring physics and astronomy to people because one day they may become scientists.

(NB: You can read a report on a public lecture that Alfonso presented here)

NSB : The last question we have, which we ask all our guests, is something that I am always keen to hear the answer to : What do you think is the best thing about living in the UK ?

Alfonso : I have been in the UK since 1988 and there are two things that I have found very welcoming and, for me, very important about this country.

One is the very strong sense of fair-play. People value it and if something is not fair, people rebel against it immediately.

And the other thing, on a much lighter note is that people value a sense of humour. A good sense of humour is something that I really like. I’m not saying something that my countrymen don’t know in Spain when I say that the British sense of humour is much better than the Spanish sense of humour because in the UK we laugh at ourselves, that is something that I always find very curious. If you look in the personal ads in a newspaper, one of the things that people look for is a good sense of humour and that is a very important quality because life is tough enough so let us laugh every now and then and we will all be a little happier.


Image Credits: Notts Uni Main Building, Notts Uni Int House, Faraday Disk, CCD, Tycho, ATLAS, London