Archive for July 16, 2009

Everyone’s Gone to the Moon

Posted in Uncategorized with tags , , , , on July 16, 2009 by telescoper

Since the media have been banging on about it all week, as have various other bloggers, I suppose I should at least mention that today (16th July 2009) is the fortieth anniversary of the launch of NASA’s  Apollo 11 mission which put the first man on the Moon. I’m reliably informed that the picture on the left shows the second man on the Moon, Buzz Aldrin, although I don’t think the costume gives much clue to the identity of the wearer.

My response to the media furore  is muted because I’m decidedly ambivalent about the whole business of manned space exploration. I’m not going to be churlish and say that all the Apollo missions did was provide America with a much-needed propaganda victory during the Cold War. I think it’s true that putting a man on the Moon was a great achievement in terms of ingenuity and organization. It’s  probably also true that it inspired many people to go into science who otherwise wouldn’t have done so. I’d even say that the sight of Earth from the Moon marked the beginning of a new age of awareness of the fragility of our own existence on our home planet and, perhaps even a step towards our coming-of-age as a species.

The reason I am ambivalent, however, is that the scientific returns from the Apollo missions were entirely negligible, at least in terms of value for money,  partly because the Apollo missions weren’t really designed to do science in the first place and partly because the Moon just isn’t very interesting…

Mankind hasn’t returned to the Moon since the Apollo series came to an end. That’s not a matter for regret, just a reflection of the fact that there isn’t much to be found there. In those forty years  astronomy and space science have moved on immeasurably through spaceborne observatories and unmanned probes. We have learned far more about the Universe  those ways than could ever be achieved by sending a few people to collect rocks from a dull piece of rubble in our backyard. In the process, the Universe has grown in size relative to the scale possible to reach by human engineering projects. The last forty years has shown us that, in retrospect, going to the Moon wasn’t really all that impressive compared to what we can find out by remote means.

Unfortunately there appears to be an increasingly vocal lobby in favour of diverting funds from fundamental science into manned space exploration, much of it aimed at the goal of putting a person on Mars.  This has not yet resulted in a commitment by the United Kingdom government to join in manned space exploration, but it is worrying that the Chief Executive of the Science & Technology Facilities Council is a failed astronaut who I fear sees this as an attractive option. Even more worryingly, Science Minister Lord Drayson seems to be keen too. It’s up to  scientists to present the case to government for maintaining investment in fundamental science and against having the budget plundered to play Star Trek.

The European Space Agency‘s Aurora programme is intended to culminate with a manned trip to Mars, at an overall cost of over £30 billion. One of the arguments I hear over and over again in favour of this programme is that it will inspire young people to take up science, especially physics. Well, maybe. But people can’t become scientists unless they have the opportunity to learn science at School and there is a drastic shortage of physics teachers these days. What’s the point of being inspired if you can’t get the education anyway? You could train an awful  lot of school teachers for  a small fraction of the Aurora budget.  And what’s the point of inspiring people to take up astronomy and space science when you’re also busy slashing the budget for research and ending the careers of those excellent scientists we’ve already got?

So by all means let’s celebrate the marvellous achievements of 1969, but let’s move on and not pretend that there is any good scientific reason for repeating them.



Posted in Biographical, The Universe and Stuff with tags , , on July 16, 2009 by telescoper

T.D.1.jpg_copyBlogging about graduation ceremonies yesterday, I was reminded that a few years ago I had to deliver an oration on behalf of a very famous physicist who was awarded an honorary doctorate at the University of Nottingham. The recipient was TD Lee (shown left) who, together with CN Yang, won the Nobel Prize for Physics in 1957 for his work on parity violation. I thought you might find it interesting to  read the text of the oration, which I just found on my laptop this morning:




Chancellor, Vice-Chancellor, Ladies and Gentlemen, it is both a pleasure and a privilege to present Professor Tsung-Dao Lee for the award of an honorary degree.  Professor Lee is a distinguished theoretical physicist whose work over many years has been characterized, in the words of Dr J Robert Oppenheimer, by “a remarkable freshness, versatility and style.”

Tsung-Dao Lee was born in Shanghai and educated at Suzhou University Middle School in Shanghai.  Fleeing the Japanese invasion, he left Shanghai in 1941.  His education was interrupted by war.  In 1945 he entered the National Southwest University in Kunming as a sophomore.  He was soon recognized as an outstanding young scientist and in 1946 was awarded a Chinese Government Scholarship enabling him to start a PhD in Physics under Professor Enrico Fermi at the University of Chicago.  He gained his doctorate in physics in 1950 with a thesis on the Hydrogen Content of White Dwarf Stars, and subsequently served as a research associate at the Yerkes Astronomical Observatory of the University of Chicago in Williams Bay, Wisconsin.

Astronomy is a science that concerns the very large, but it was in the physics of the very small that Professor Lee was to do his most famous work.  After one year as a research associate and lecturer at the University of California in Berkeley, he became a fellow of the Institute of Advanced Study in Princeton and, in 1953, he accepted an assistant professorship position at Columbia University in New York.  Two and a half years later, he became the youngest full professor in the history of Columbia University.  During this time he often collaborated with Chen Ning Yang whom he had known as a fellow student in Chicago.  In 1956 they co-authored a paper whose impact was both immediate and profound.  Only a year later, Lee and Yang were jointly awarded the Nobel Prize in Physics.  Professor Lee was thirty-one at the time and was the second youngest scientist ever to receive this distinction.  (The youngest was Sir Lawrence Bragg who shared the Physics Prize with his father in 1915, at the age of twenty-five.)

It is usually difficult to explain the ideas of theoretical physics to non-experts.  The mathematical language is inaccessible to those without specialist training.  But some of the greatest achievements in this field are so bold and so original that they appear, at least with hindsight, to be astonishingly simple.  The work of Lee and Yang on parity violation in elementary particle interactions is an outstanding example.

Subatomic particles interact with each other in very complicated ways.  In high energy collisions, particles can be scattered, destroyed or transformed into other particles.  But governing these changes are universal rules involving things that never change.  The existence of these conservation laws is a manifestation of the symmetries possessed by the mathematical theory of particle interactions.

Lee and Yang focussed on a particular attribute called parity, which relates to the “handedness” of a particle and symmetry with respect to mirror reflections.  Physicists had previously assumed that the laws of nature do not distinguish between left- and right-handed states: a left-handed object when seen in a mirror should be indistinguishable from a right-handed one.  This symmetry suggests that parity should be conserved in particle interactions, as it is in many other physical processes.  Unfortunately this chain of thought led to a puzzling deadlock in our understanding of the so-called weak nuclear interaction.  Lee and Yang made the revolutionary suggestion that parity is not conserved in weak interactions and consequently that the laws of nature must have a built-in handedness.  A year later their theory was tested experimentally and found to be correct.  Their penetrating insight led to a radical overhaul of the theory of weak interactions and to many further discoveries.  Physicists around the world said “Of course!  Why didn’t I think of that?”

This classic “Eureka moment” happened half a century ago, but Professor Lee has since made a host of equally distinguished contributions to fields as diverse as astrophysics, statistical mechanics, field theory and turbulence.  He was made Enrico Fermi Professor at Columbia in 1964 and University Professor there in 1984.  With typical energy and enthusiasm he took up the post of director of the RIKEN Research Center at Brookhaven National Laboratories in 1998.  He has played a prominent role in the advancement of science in China, including roles as director of physics institutes in Beijing and Zhejiang.

Professor Lee has received numerous awards and honours from around the world, including the Albert Einstein Award in Science, the Bude Medal, the Galileo Galilei Medal, the Order of Merit, Grande Ufficiale of Italy, the Science for Peace Prize, the China National-International Cooperation Award, the New York City Science Award, the Pope Joannes Paulis Medal, Il Ministero dell’Interno Medal of the Government of Italy and the New York Academy of Sciences Award.  His recognition even extends beyond this world, for in 1997 Small Planet 3443 was named in his honour.

Chancellor, Vice-Chancellor, to you and to the whole congregation I present Professor Tsung-Dao Lee as eminently worthy to receive the degree of Doctor of Science, honoris causa.