Triki Galaxiki

June 30, 2007

I was just browsing the New Scientist Space Blog, and found a post about a new web-enterprise called Galaxiki. (Galaxy Wiki, geddit ?) It says it is “a fictional online galaxy created, maintained and owned by its Community”. It boasts that you can join free, and it has a kinda community pitch… but it looks like a business to me.

You zoom in on a grid and end up picking your very own star .. and then gee whizz, you can buy the star and edit its properties !! Of course, being a community thing, you can pay anything you like .. as long as it’s at least 5 euros….

So in some ways its like an updated version of that scam where you sell someone a star and give them a certificate, except the star isn’t even real ! You just make it up.

On the other hand, its not really like one of those old scams, as the guy who designed and built all this has worked really hard. Its a lovely toy. If it was painted clearly as a money making business, I would be completely happy with it. I just feel uncomfortable when you can’t quite tell whether this is a business with a cynical “open community” veneer, or an intrinsically open thing with a business veneer.

But maybe I am being a daft old purist lefty. This is C21. Its ok to make money. Hey, we all have Google ads on our blogs, don’t we ? Errr.. not me actually. I am not against making money. I just don’t like all that clutter. Adverts just add noise and confusion to life. How is a chap supposed to see past the ten thousand things ?

On one page, it says “this is not a research tool”. Dead right. I picked a star at random and got TAH357. Nobody has bought it yet and it has no lifeforms. Apparently – big sigh – its a “yellow giant class star”. Aint no such animal folks.

Elvis and Princess Diana : suspicions grow

June 30, 2007

Coo. Weird. Several more people have actually read my wacky post about Princess Diana, Elvis and the Dinosaurs. And it seems I am not alone in my suspicions about Elvis and Princess Diana being strangely connected. Tomorrow is the 10th anniversary Diana memorial concert. Yuch. But to a close approximation it is also the 30th anniversary of the death of Elvis. There are many other spooky coincidences, explained in a wonderful web page called “Elvis lives, Princess Dies“. Elsewhere, Wakeme2008 says he has seen Princess Diana and Elvis together in Starbucks, and Jenny Kim is keen to know if they have been seen hanging out together at Walmart. This deep connection has also inspired Great Art.

A London Tourist web site, LondonNet, is encouraging readers to submit
their Diana conspiracy theories
. Waddya think?

Jeez. I’ve been working too hard.

The sixty three year lifetime of nebulium

June 24, 2007

This evening I rediscovered the story of Nebulium. Nebulium doesn’t exist. But its “discovery” was a key step in both astronomy and quantum physics. It took sixty three years to realise what was really going on. What have we “discovered” recently that doesn’t mean what we think it means ? Dark energy maybe ?

I was looking for a book, but ran across an old favourite, and plucked it out instead, the way you do. The old favourite was an Edwardian book about the life of William Huggins, one of the founders of modern astrophysics – the man who turned the spectroscope to the stars. Huggins is a scientific hero, but its also a lovely wee book. Huggins smallIts one of “The People’s Books” – cheap pocket sized summaries of everything a person should know – from Inorganic Chemistry to The Life of Caesar through Kant’s Philosophy and Women’s Suffrage to The Stock Exchange and The Crusades. When the biography of Huggins was published in 1913, there were eighty four titles; by 1920 (the lastest volume I have) there were a hundred and thirty three. Whenever I drift by a second hand bookshop a magnet pulls me in and I check for People’s Books… I have twenty eight of them. Here is a picture of the frontispiece of the Huggins book.

Any other fans out there ? There seems to be little information on the Web …

Anyhoo … Huggins, working from his home in Tulse Hill in the suburbs of London, turned a spectroscope to the stars, and found them to contain Hydrogen, Sodium, Magnesium, Calcium, and Iron. Astronomy turned into Astrophysics in 1864. (You can read the real thing in Huggins and Miller 1864a). This was the start of the long confused path that led through Rutherfurd, Secchi, Pickering, Fleming and Cannon to the modern classification of stars. In 1866 Huggins took the first spectrum of a Nova, finding Hydrogen in emission, and in 1868, he took the first spectrum of a comet, finding, amongst other things, ethylene. These things alone would put him amongst the giants of astronomy; but his fame rests on the observations of nebulae.

On August 29th 1864, Huggins turned his spectroscope to the Cats ECats Eye Nebula (HST)ye Nebula in Draco. He was amazed to find, not a continuous spectrum with dark lines, but a single bright emission line. (A few other lines were found later). He correctly deduced that nebulae were not aggregations of stars, but glowing gas. These observations and more were formally published in a series of papers starting with Huggins and Miller (1864b). However, my wee People’s Book contains a beautiful and moving informal account, written later by Huggins for the “Nineteenth Century Review” of 1897. Here is a link to a photo of the relevant pages.… I hope you can read it ok.

Now here is the problem. The “Chief Nebular Line” at 5007 Angstroms wavelength, had never been seen in a laboratory spectrum. It must be from a new substance, not found on Earth, which became known as “Nebulium”. (I am not sure when the word was first used.. ) This was a popular game in the 1860s. In 1868, Norman Lockyer found mystery lines in the Sun, which he decided were likewise due to a new element, christened Helium. Over the coming years, Helium lines were also found in nebulae, and nebulium lines found in novae, and all this spectroscopy was a major industry. By 1895, Helium had been found on Earth – William Ramsay managed to isolate it from the mineral Cleveite – but Nebulium was still confined to the Heavens, and was the subject of much speculation. By 1911, J.W.Nicholson had developed a full theory of the Nebulium atom, and calculated its size.

Finally in 1928 Ira Bowen solved the puzzle, in a classic paper. By this time, we knew about quantum mechanics, and how emission lines arise when atoms are excited, and then spontaneously decay to lower energy states. Some energy states are “metastable”; you have to wait a really long time before the spontaneous decay happens. In practice it never happens, as a collision with another atom always kicks it out of the excited state first. At least thats true on Earth … but in nebular gases the densities are so low these collisions happen very rarely .. and so the “forbidden” lines do occur after all. The Chief Nebular Line is not from Nebulium .. but from plain old Oxygen.

So all that time the wondrous nebulium did not exist. But the nebulium lines were a clue to the fundamental nature of the material world .. if only we had known.

So in modern times we measure the brightness and redshifts of distant supernovae, and find the universe, to our considerable surprise, to be accelerating. In the context of modern cosmology this requires a vacuum energy. Vacuum energy is proposed in some particle physics theories, but of a size many orders of magnitude different. This is something stranger, something new. The concordance cosmology has the universe made of ordinary (baryonic) matter, dark matter (non-bayonic particles), and “dark energy” .. a completely new substance … hmm..

Come back in sixty three years and maybe we will know what the hell this means.

At last my cynical ploy works

June 18, 2007

So a few weeks into blogging I was wondering how you get readers, and noticing how the Web is full of conspiracy nuts. Then I remembered how someone once suggested to me (many moons ago) that the ultimate science headline would be “Black Hole killed Dinosaurs – says Princess Di”. Right I thought, cynical Google fodder coming up. So I writes me a post full of bizarre invented stuff about Princess Di, Elvis, Dinosaurs, MI5, and Jade Goody. Not a sausage. Nary a view on that post. For months. Then lo ! Today FINALLY someone entered “Diana killed by MI5” into Google and found my post …

Will this spread ? Will I really start a theory that Diana was killed by Elvis Presley ?

Treating String Theory with the respect it deserves

June 18, 2007

Well I spent the last few days musing about writing a post on computational biology .. how pretentious is that … but instead here is a picture of a cute cat testing string theory. Thought I should get there before the Cosmic Variance Team.

LolCats is in the Word Press Top Ten EVERY DAY. I keep trying not to like it but I can’t help it.

This one comes from a blogger called TechnoBuddhist. What does the Bad Astronomer make of that ?

Quasars, Donuts, and the Unified Faith

June 8, 2007

Six a.m. in a Bavarian Monastery. I am woken again by the bloody bells. Worry not, dear readers, I have not become a monk. The ancient Kloster Seeon has been turned into a hotel and conference centre, and I am here with a hundred astronomers arguing about “Obscured AGN across Cosmic Time”. But in some ways this is a gathering of believers – the Church of the Unified Faith – and its an interesting example of science as a sociological process.

Active Galactic Nuclei (AGN) and their big cousins the Quasars come in two flavours, Artists impression of the torus - courtesy of ESO
imaginatively called Type-1 and Type-2. Since the late 1970s various folk including yours truly have suggested that Type-2s are actually the same as Type-1 but seen edge on through obscuring muck. This is known as the Unified Scheme. Grand Title for a kinda simple idea. In 1985 Antonucci and Miller found particularly convincing evidence that the idea was correct, and in 1988 Krolik and Begelman put forward a theoretical explanation involving a dusty torus surrounding the quasar. Since then every observer compares their data to “the torus model”, and every artists impression of a quasar has this nice neat obscuring torus as well as accretion disc, jets, and so on.

The trouble is, there are at least as many Type-2s as Type-1s, so the obscuring torus has to cover a large fraction of sky as seen from inside the quasar. So the torus is not a swirling disc but a great fat rotating donut. Making a fat rotating thing is hard. Cold rotating things are always thin, like Saturns rings. Stars are fat rotating things, but they’re hot. Various forced attempts have been made to fix this problem. The latest one was put forward this week by Julian Krolik, who argued that the torus is kept puffed up by the radiation pressure from the central quasar light. Nice idea, but not yet clear that its stable, or that it fits the facts well enough.

Another option came from me, arguing that there isn’t really a rotating donut at all, but a severely warped disc – fuel coming from large distances is rotating in a different plane to the quasar disc, and as it tilts and precesses on the way down, it ends up blocking much of the sky. People were interested in the idea, but many were perturbed. In torus land, Ski Antonucci is the Founder of the Faith, and Julian Krolik is the Bishop of Rome; I am I guess one of the Cardinals, seen as responsible for the variant known as the “receding torus model”. People love this, as its basically one line of algebra and so dead easy to compare your data to. People kept asking me “so you don’t believe in the torus anymore ? But you’ve been working on this for years.”

This is is unsettling, not just because of the idea of belief in science, but because you are pressured into buying complete packages. Talk after talk at this meeting claimed that their data “supported the torus model”, to which my reaction was “err.. depends what you mean”. Usually the data supported the general idea of unification of Type-1 and Type-2; sometimes it supported the idea that obscuration is axisymmetric, sometimes that it is geometrically thick ..but showed that there is a rotating molecular donut ? Gimme a break. But once a successful model appears, it swallows all the things that made it up, and is very hard to break apart and re-assemble with some new parts.

This is understandable, not because scientists are conservative, but because science is hard work, and because they have careers to make. This is especially true for young scientists. It is very hard work understanding how your instrument works, collecting the data, reducing it carefully, mastering the background theory, and reading the huge literature. You are desperate to make an impact, to tell a story with your work, and need some organising mental framework. If the world is all scepticism and ambiguity you are sunk. So you cling onto the popular model until the facts make it crack, and then you jump ship to the new fashionable model.

So this of course is just what Thomas Kuhn said in his famous book, “The Structure of Scientific Revolutions”. At heart, the scientific process is sceptical and logical – Conjecture and Refutation, as another famous book by Karl Popper has it. But the realities of human debate, the pressures of the sociological process of science, and the need to think within an organising framework, all lead to resistance to change. This is not conservatism – scientists love to be radical in principle – but inertia.