Chris Lintott’s Universe

This weekend is proving to be one of the more bizarre I’ve had for a while. I’m writing this from a barn on a pumpkin farm about two hours’ drive south of Chicago. I’m here for the Chicago Astronomical Society’s Astrofest and I’ll be talking later about Galaxy Zoo (of course).

I can’t resist sharing this video with you, though. The Adler Planetarium run a high altitude balloon programme using students and interns (and a weather balloon six-foot across) to launch instruments more than twice as high as your average Boeing 767 reaches. For reasons best known to themselves, one of these flights carried a marshmallow bird called a peep along with it.

You can watch the flight of the Peep below :

The witch is dead! Or at least the Discovery experiment soon will be, as we’ve decided to go our separate ways. I’ve enjoyed the experience of writing more, and will endeavour to keep this place up to date and full of juicy astronomy.

Credit : Justin Bilicki, the winner of the Union of Concerned Scientist’s Science Idol competition.

Hat Tip : Phil

Jim Gunn from Princeton – one of the founders of the Sloan – is presenting the final conference summary. A large part of the design was influenced by the impact of people coming into astronomy from other parts of physics, doing things in the x-ray, the radio and the infrared and who were used to working with data, not with the pictures that were the stock in trade of the optical astronomer. Sloan was supposed to fill the gap, taking both images and data in the form of spectra.

The crucial technology were the fibre optic cables that allowed hundreds of spectrographs to be fed at the same time. Without them, the survey would have taken a thousand or so years assuming that everything worked with 100% efficiency. The new technology made much more rapid progress possible, and Sloan has touched every part of astrophysics.

Jim started his run down with the work on large scale structure. Among the surprises were the work on gravitational lenses, which it had never occurred to anyone might be possible. The net result is that our current cosmology is much better than we have any right to expect, and as Jim said ‘there are no obvious cracks – yet’. However, he warned that eventually as data improves it will crack, and said he’d be very surprised if it didn’t.

The study of galaxies themselves has been revolutionized by Sloan. The spectra were of a much greater quality than was necessary just to determine the distance to the galaxies SDSS targeted. Jim’s slide claims that establishing the properties of modern day galaxies was one of the primary purposes of the Sloan. The headline result is probably the discovery that large populations of galaxies can be divided into red and blue sub-populations. One of the current challenges driving research as a result is the need to explain how sufficient galaxies move quickly from the ‘blue cloud’ to the ‘red sequence’, let alone trying to work out what happens to them once they are there. The majority vote is that black holes have something to do with these mysteries, but the details are very sketchy.

Yet we have still made huge progress; as Jim said, when Sloan started we didn’t even know enough about galaxies to ask these questions, let alone to start answering them. Plenty of work has also been done on galaxies’ active cousins, the quasars, and on the Milky Way itself. The most striking thing – which has crept up on my consciousness for starters – is the acceptance of the idea that the Milky Way has grown by the accretion of smaller satellite galaxies.

Jim’s award for the most unsettling talk goes to ‘Pierre Bergeron’ whose talk on white dwarfs – the dense remnant of Sun-sized stars – lead to conclusion that the hydrogen atom, at least in these extreme conditions, is ‘not well understood’! In a more reassuring pocket lie some of the solar system work (the talks on which I missed by being busy elsewhere) where great strides have been made in identifying asteroids, ruling out threats to Earth.

Supernovae – exploding stars – have been the gold standard for cosmology for the last decade, but at current errors we’re getting close to the point where we have to understand the explosions themselves in order to make further progress. A task for the future, probably, but there are a new set of surveys on the horizon. What advice can the Sloan team offer them?

The most important is probably ‘do it right’ rather than take shortcuts. More interestingly, the lesson from Sloan is not to design surveys which are suited only for one task, but can do a whole host of things, most of which you haven’t thought of yet. Finally, one last discovery. It really is possible for hundreds of astronomers to work together across many institutions with very few constraints on who should do what. That’s something that just wasn’t known when Sloan started, and it’s illustrated by the fact that four of Jim’s academic grandchildren gave talks at this conference.

That’s a suitable end to a wide-ranging conference, so I shall leave it there. I hope you enjoyed my coverage.

Lots to write about from my current trip (Hello from Chicago) but for now let me send you to this week’s all singing all dancing Carnival of Space.

It’s becoming increasingly difficult to know where one stands when writing about – or doing – science. Instead of waiting for the peer review process to take its course and for journals to print the received wisdom, life on the cutting edge is about debating papers released to astro-ph, a slightly policed archive of papers submitted by academics when reviewed, but also sometimes when submitted to the journals or even before. Writers are picking up on that, and that’s fine – I love the fact that you can now read an article on a blog or in New Scientist and with a click be reading the paper.

Some projects have more problems; we’re struggling with Galaxy Zoo to learn what to say when – more on that tomorrow. For now, here’s Emily on what it seems will always be known as the ‘Phoenix flap’.

As many as 35% of Britons believe that the Moon landings were fake? apparently so, thanks to a survey commissioned by the people behind the X-files movie.

I don’t believe it. No, really, I just don’t believe it. People are cleverer and more discriminating than that. It’s well known that these surveys – or any piece of research – is strongly influenced by the form the question is in. I can’t find the exact questions used for this survey anywhere (I’ll send an email to the PR company, but I strongly suspect it will do no good) but I’ll bet you anything the question was phrased as something like ‘Some people believe there is evidence to support the following theories. Which of them do you agree with?’

Seemingly fair, but enough to access the unconscious bias that makes us want to agree with the person we’re speaking to. If some people believe these things, then perhaps there is evidence after all and I’d better just say yes. The same survey found that 3% of people believe that ‘The world is run by dinosaur-like reptiles’ and that – the belief and the number – sound like rubbish to me.

I enjoyed this honest piece in Saturday’s Guardian from Nick Laid, a poet struggling to write about modern astrophysics.

Can complexity of this kind be versified? Poetry evokes better than it explains. There is also, for the poet, the danger of simply being seduced by new terminology, the taste of exotic words. The poem becomes a list. And there is the lack of shared reference. Mention a telephone or tree, a marriage or goose-bumps, and we have some similar notion of what is meant. Our experiences of science are either abstract or mediated. How far can we imagine what a cell is like? Or a radio wave? Outer space comes to us only through telescopes and satellites.

And with space, the measurements cannot be apprehended. How do you describe things of this size or length of time, this speed or heat? Experience, being broadly empirical, gives us no meaningful terms.

The latter problem is one I understand – the true answer to the sometimes half-awed question of ‘how you get your head round such large numbers’ (the age of the Universe, the size of the Galaxy) is that you don’t, you just learn to use them. But the rest of this poet’s lament? I’m not so sure. Is it really easier to describe what a marriage between two people means than it is to talk about the red blood cells that flow through their hearts as they beat together?

I don’t mean to belittle the hardship of the poet’s task; there’s a reason I write in prose and fairly workaday prose at that when I try to describe the Universe. But Feynman, as so often, had it right:

It does not do harm to the mystery to know a little about it. For far more marvelous is the truth than any artists of the past imagined! Why do the poets of the present not speak of it? What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?

The language we use as scientists is often strangely divorced from that in the rest of the world; it makes sense to me to describe something as trivial when we can see how to get to the answer, whereas non-science friends may get upset by the description. To take a second example, consider the word ‘significant’; for me, loaded with statistical meaning and for others a vague statement. These tangles get worse when worlds collide – mathematicians will consider any of the language in my papers unbelievably sloppy – and worse of all when a term escapes the scientific lexicon and takes on a glorious life of its own; ask any physicist to define a ‘quantum leap’ and the answer you get will be very different from the one you expect.

All of this musing was triggered by a wonderfully discursive post on the Language Log blog about the origins of the ‘black’ part of a ‘black hole’, triggered by a reported incident when someone felt it had been used in a racist context. Language Log is essential reading for anyone who enjoys looking at language, whether scientist or not, by the way.

Sample quote : I’m afraid, though, that the search for collocational analogies for X hole, beyond X=black and X=white, is hampered by interference from unrelated patterns.

I’m still in the US, where we’ve been filming pieces for the next few Sky at Nights. I need to write up the amazing two days we spent in mission control for Phoenix, but for now the Discovery blog has details of the Large Binocular Telescope and the alien-hunting Allen Telescope Array.

Having left the Sky at Night team crowing about their upgrade to first class on the way home and have headed off to visit Pamela. I’m giving a public talk tomorrow (Monday) night about Galaxy Zoo and citizen science more generally, and for those who can’t join us we’ll be broadcasting the event online.

The link is here, although you should be able to watch and chat below. The talk starts at 7pm Central, 1am Tuesday morning BST and midnight GMT.

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