Twitter has been one of the big game changers in social media on the web in recent years.  Those who know me are aware that I’m an active tweeter. In fact, those of you who know me through this blog are very likely to have found me through Twitter. I have statistics to tell me that, it’s rather neat.

So much has been written about the pros, cons and dangers of Twitter in general or in the context of science specifically, I feel this post is moot – but I’ve promised several times to write about Twitter and astronomy,  and it’s about time I delivered on that. I should start off by saying that most of the things I like about Twitter are not related to astronomy per se – I’m sure non-astronomers have a very similar experience. I’ll also concentrate on the person-tweeter, rather than the institute-tweeter or telescope-tweeter – those are whole other topics. So here’s what I think.

At its very simplest, twitter is the ultimate vehicle for ultra-rapid dissemination of information. It’s no different with science. I’m so much better informed about science news from around the world than I ever was before: whatever new instrument comes online, new discovery is made, or funding body goes into crisis, one of the 200-odd scientists I follow on twitter is likely to tweet about it in the space of a couple of hours, before it ever appears on an official channel.

Even better, a few people might have a conversation about it that I can follow, which I can join, or just follow to learn about the significance of the news item.

Social networking, you may be surprised to learn, is all about networking. We take networking very seriously in career development, why do we look down on online social networking as something juvenile and frivolous? Networking via social media like Twitter is even easier than real life networking. You don’t have to do it while you’re standing awkwardly with a glass of wine and some finger food, trying to keep your jetlag at bay. You can have engaging conversations with peers or influential people in your pyjamas on the sofa.

Online social media also break down the fence of affiliation or seniority. Top-dog astronomers on Twitter aren’t scary Professors anymore. They’re @e_astronomer, @defjaf and @telescoper. Sometimes they tweet about the weather, their kids, or that they cried over a cartoon. For highly competitive careers like science, full of (let’s be honest) snobbery and hero-worship, a medium like Twitter breaks down the social barriers and brings back a bit of much-needed humanity.

Plus, twitter gives you the opportunity to mingle with colleagues from other fields, whom you may not otherwise meet at conferences. If you don’t have the funds to attend conferences, twitter allows conference participants to keep all the rest of us in the loop with what’s happening. Several large astronomy conferences in recent years have had a significant twitter presence, such as the AAS, the Herschel first results conference in Noordwijk in May 2010 or the UK National Astronomy Meeting. Others, like .Astronomy, almost certainly thank a big part of their success to an online social media presence.

There’s a broadly held feeling that scientists tweeting leads them to engage with the public. It certainly has that potential, but I’m not sure that that actually happens. As with many forms of social media, the hard outcomes and benefits are not routinely and systematically studied, and the little research that does get published on the subject sometimes misrepresents or misinterprets the history and relevance of science in the social media (if you know of something good, please talk about it).

Where engagement clearly has occurred, however, is between scientists from different fields, and between scientists and the media. It’s allowing researchers from niche sciences like astronomy to embed themselves in the broader research landscape. The funding cuts currently being inflicted on the British astronomy and nuclear and particle physics communities were widely discussed on Twitter (here’s an archive and my post), first by a small group of physicists and astronomers, but quickly by a broader group of tweeting scientists. In the run-up to the British elections in May, those scientists participating in the  #stfc debate became active proponents of the #scivote movement that aimed to bring attention to science and engineering policy.

Even traditional media, often slow to adopt new technologies, these days have many twitter feeds for diferent subjects and types of content. Some excellent science writers, such as Mark Henderson of The Times or Dutch astronomy writing legend Govert Schilling, actively take part in conversations about science via twitter. That can only lead to a more trusting and mutually beneficial relationship, and better science reporting. Just this week, the Guardian launched a science blogs section that brings together several well-respected science bloggers – more about that later.

A lot of twitter-sceptics seem to think that twitter is one more source of background noise to destroy our abilities to focus on our work. I’m pretty sure that twitter hasn’t negatively affected my productivity or my attention span. I spend just as much time browsing the web as before twitter, only that now I have more interesting content to read while I’m taking a break. And when I’m really busy, I just switch my twitter client, along with my email inbox, down for the day.

There are some caveats. The style of twitter is very colloquial, chatty and laid-back. That doesn’t mean it’s a good idea to tweet everything you’re thinking or would say to your friends. If you want to take twitter seriously as a networking tool, you have to treat it as such. And as twitter feeds are generally public, you have no control over who reads what you say.

Twitter, like any other web-based medium, attract herds and mobs, and is perfect for spreading misinformation.

Finally, twitter takes some time. I found that it took me about 6 months of not-quite-getting-it, before I’d found the people whose content I was interested in. And just maybe it’s not for you, which is fine too. But before you make up your mind, do give it a try (a great intro guide to twitter here, find scientist friends here). Don’t be that person who bitches about twitter without having tried it. We tweeters really don’t like them.

This video from Arecibo observatory has been doing the rounds on the interwebs. It shows the increasing number of known asteroids in the Solar System over the period 1980 to 2010. It gets very pretty around the 2:00 mark, which roughly coincides with the year 2000 (see the time ticker in the lower left corner).

Something radically new is in the air: new ways of understanding physical systems, new ways of thinking about thinking that call into question many of our basic assumptions. A realistic biology of the mind, advances in evolutionary biology, physics, information technology, genetics, neurobiology, psychology, engineering, the chemistry of materials: all are questions of critical importance with respect to what it means to be human. For the first time, we have the tools and the will to undertake the scientific study of human nature. — Edge.org

In late July, Edge organised a conference on the science of morality, gathering together a number of scientists, philosophers, psychologists, to talk about the new ways that we’re studying human morality, and the questions we face in this difficult but important discipline.

I’ve posted here the first part of the talk by Jonathan Haidt, which is excellent (full video here). Haidt, Professor in the Social Psychology area of the  Department of Psychology at the University of Virginia, talks about a new analogy for morality that revolves around taste, and has developed five key foundations of morality, parallel to the five kinds of taste receptors foudn on our tongues: care/harm, fairness/cheating, group loyalty and betrayal, authority and subversion, sanctity and degradation. He argues  that “moral systems are like cuisines that are constructed from local elements to please these receptors.”

His talk is full of good insights that touch on issues relevant to science, such as the confirmation bias – or, the tendency for people to search for evidence to confirm their already-held beliefs. Confirmation bias is an issue that pervades scientific research and literature – how often have you allowed new data, or a colleague’s arguments,  to fundamentally change your mind about something? Our inability to rise above it, despite being fully aware, is quite an interesting aspect of the way our minds work.

The text of all the talks is posted online on Edge’s webpages for the conference, and there’s a lot of interetsing reading material there from the other invitees. There are also video recordings of each talk (also mp3 files for download) and the subsequent discussions.

SPIE, the somewhat bizarrely acronymed International Society for Optical Engineering, is a household name for astronomy instrumentalists. Organiser of the biggest global conference on telescopes and instruments, SPIE publish a number of decent journals and some very useful books. I’m a particular fan of their Field Guide series, which are small spiral-bound quick-reference booklets on topics like adaptive optics,  spectroscopy or optical testing. I recently saw that SPIE have now released a free iPhone app for their Field Guide to Geometrical Optics, by John Greivenkamp.

SPIE have released a number of iPhone apps. I tried their conference planner earlier this summer, at the San Diego Astronomical Telescopes conference. That was not a success due to the unfortunate timing of the iOS4 release just before the conference and the updated iOS4-compatible app being held up by the app store. That was bad luck, so I was keen to give them another go, and I’m glad I did.

The Field Guide goes through all the standard formulae for reflection, refraction, optical path length, magnification, etc, as well as aberrations and optical systems, and the information is presented very legibly in the app. There are some great added-value features too: some of the key equations are tappable, which allows you to perform the calculation described in the equation with values of choice, like so:

Key graphs can be viewed bigger, without surrounding text. There is a separate listing just for the equations, and you can also record notes.

I’m really impressed with  this application, it looks nice and has some excellent features, and I think the Field Guides lend themselves really well to viewing a mobile device. Best of all, it’s also free! Get it in the app store here.

The global astronomy community is buzzing this week after the publication at last of the Decadal Survey for Astronomy & Astrophysics by the US National Academy of Sciences, which will serve as a roadmap for US astronomy for the coming decade. Following a flurry of tweets and live blogs during the presentation of the report by the Chair of the review, Prof Roger Blandford, which was broadcast live on the web, I’m sure the report will be read, chewed over, and discussed at length online in the weeks to come (see e.g. here, here, here, here); if you’re interested, the report is publicly available here, all 225 pages of it – happy reading.

It’s also worth noting that the European astronomy community produced a similar document, the Astronet roadmap, in 2008. The report, equally beefy, is available from the Astronet website.

I just finished reading In Bluebeard’s Castle, a collection of lectures by George Steiner from 1971, presented as  “Notes towards a Redefinition of Culture”. Steiner is a fascinating writer, he displays an huge breadth of knowledge in his writing. When commenting on a concept as broad as that of “culture”, this allows him to create connections between the many aspects that it encompasses in original and exciting ways. The World Wars and the Holocaust feature heavily in his writing, and indeed WWII serves as a pivotal point in his discussion.

In the first essays of the book, Steiner performs a kind of literary archaeology, highlighting certain social movements and worldviews of the late-18th and 19th centuries, as they are reflected in literary works and philosophic writings of the time. Much of what he talks about in these lectures, the rapid pace of progress that characterised the Romantic era and the dynamism it brought to Western society, would, by the way, really appeal to anyone who read and enjoyed the excellent book The Age of Wonder. Later he talks about the horrors of WWII, and how they fundamentally changed the notion of culture in the post-war era.

The World Wars, he argues, once and for all destroyed the chain of tradition that typefied our Western culture, and a post-culture has emerged from the wreckage that no longer carries the confidence in a better future. And he identifies two new literacies that have risen from the ashes of our pre-war culture: that of music, through modern technology available to all; and that of science and technology, enabled by the computing revolution (remember – this was written in 1971).

Reading this made me wonder: how have political events in the last 60 years affected science and astronomy? Let’s look at the outcome of the Decadal Survey, for example. Why did the panels prioritise the “top” areas? The outcomes of the survey are the result of almost 2 years of consultation amongst the best and brightest in the US community, these scientists are supremely aware of the problems and opportunities that we face in astronomy. Yet these senior astronomers too are embedded in the fabric of society. It would be naive to think that they are unaffected by societal and political movements that aren’t in se related to astronomy. How do their choices and recommendations reflect the time we live in?

Consider the consistently high priority given to exoplanet research, and the detection of Earth-like, potentially habitable, exoplanets in particular, by funding agencies and in the popular media. We could easily ascribe this to a certain disillusionment with our own world: despite all our progress, we’re destroying our planet at an ever-increasing rate, and the new globalised world is still a hugely divided and dissonant place. Is our fascination with new worlds simply a sign that we’re tired and depressed at the sight of our own?

In the introduction to his Spheres trilogy (not available in English, German here, Dutch here), German philosopher Peter Sloterdijk talks about the Earth’s climate. Since Copernicus, he argues, science has removed our planet ever further from the central position it so long inhabited in the known Universe. The Sun rose and set around the Earth, the planets moved around us along the heavenly sphere. Modern cosmology has left humanity feeling a little chilly and exposed in the presence of a cold dark expanse. The atmosphere acts as our protecting sheath, the womb that feeds us, our final immune system. With this picture he places our obsession with the changing climate in a broader context of our changing society and world view. He elaborates on the idea in the second part of the trilogy but at my current reading rate I don’t expect to reach that before 2011 – it’s a hefty tome.

While our fight against climate change and disease have a fundamental goal that is easily grasped on a very basic level – the survival of the species – the driving forces behind astronomy are less clear. The pathway from understanding dark energy to improving the human condition is certainly more convoluted. We talk about goals and priorities, but what is the goal, and how will the priorities for the next decade help us achieve it?

Big Data got a huge vote of confidence in the Decadal Survey, with large-scale surveys topping the priority rankings for both ground- and space-based future facilities. Why are we convinced that the answer lies in the collection of more photons, the generation of more data, than we can ever dream to inspect, let alone analyse or sensibly interpret, by the current cohort of scientists? The idea that we should collect more data just because we can seems a little simplistic. Have we lost faith in imagination and creativity?

Perhaps, Steiner suggests,

We shall [...] open the last door in the castle even if it leads, perhaps because it leads, onto realities which are beyond the reach of human comprehension and control. We shall do so with that desolate clairvoyance, so marvelously rendered in Bartók’s music, because opening doors is the tragic merit of our identity.

We find ourselves today on the cusp of new breakthroughs in the fundamental understanding of the Universe. In 10 years’ time the Standard Model of particle physics may well have been tweaked, we are likely to know what the nature is of dark matter, perhaps understand dark energy. Looking back on the early 21st century, how will the 25th century historians and philosophers of science interpret our scientific activities and achievements in the context of the geopolitical and geo-economic situation? How will these new discoveries redefine our culture?

Maybe the goal, as they say, is in the journey. And the fact that we’re undertaking it despite the lack of evidence that it will render our lives more peaceful or more prosperous,  all the more admirable.

For over three years now I’ve been working here in Leiden’s instrumentation group. My time here in Leiden is coming to an end – I’m sad to leave but such is the life of a postdoc, and I’m excited about new things ahead (more about that later). I’ve written here about my own work on a few occasions, here’s a few examples:

Making my software open

MIRI crosses the pond

Future facilities: Coming quite close now actually

Today I’m in….

If my work sounds like fun to you, and you have a PhD and experience in working on instrumentation projects, why don’t you apply to join the group?

I’ve enjoyed my time in Leiden immensely, both from a personal and professional perspective. The Observatory sets a high standard to its staff and students, but is very open and inclusive with a great “can-do” attitude. So if you’re passionate about your science, it’s great place to push the limits of your skills and creativity. If you’re interested, check out the ad on the AAS register and apply!

Love xkcd!

The James Webb Space Telescope featured in last night’s Late Night with Jimmy Fallon!

As many of you know, I had a bit of an accident a couple of months back during and ended up with a limb out of action and a pair of crutches. Unexpected as these things are, things were pretty chaotic for a while. But somehow I managed to eat, sleep, get to work most days, even enjoy a few foreign trips, and generally not go insane. I attended several interesting and enjoyable conferences, hobbled around Venice on crutches, fell over in Venice on crutches, and had a super holiday exploring California.

I don’t usually get personal on here, but I thought a quick note of thanks was in order for everyone who helped me out these past months, kept me well fed, hydrated, mobile and reasonably sane – old friends, new friends, colleagues, acquaintances, some really entertaining taxi drivers, weirdos in Texas, and of course family and extra-special friend. I hope you never need me to return the favour, but if you do ever find yourself face down on a basketball court, give me a call. Big thanks to all of you.

Image: C. Odman

Reconstructed image from near-IR interferometric observations of IRAS 13481-6124 using VLTI/AMBER

In my previous post on the Zooniverse Project IX I’m involved in, I talked about the importance of star formation in the Universe and some of the difficulties we face in studying it. Some big unanswered question particularly remain in our understanding of how massive stars form. Fittingly, the latest edition of Nature has a paper on a nice result in the study of massive star formation: a detection by direct imaging of an accretion disk around a massive young star.

Massive stars form in far smaller numbers than the regular run-of-the-mill stars, like our Sun. They also have far shorter lifetimes, exploding in cataclysmic supernovae after just millions, rather than billions, of years. Another difference between high and low mass stars lies in the sequence of events in their earliest years: low mass stars stop accreting new material once the stars have “turned on”, and the radiation from the new star blows away the surrounding envelope. High mass stars, however, manage somehow to continue accreting new material even after they’ve started emitting the ionising radiation that will slowly dissipate their natal clouds.

How large amounts of gas can find their way onto the star despite the outward force of the emitted radiation is tough to understand. A paper by Krumholz et al (2009) showed via modelling how non-spherical accretion scenarios, like filaments or disks, could play a role in channeling the accretion flow into the star. Accretion disks are ubiquitous around young low-mass stars, but around massive forming stars they had, despite ample circumstantial evidence, never been directly imaged.

In their Nature paper, Stefan Kraus of UMichigan at Ann Arbor and collaborators from Germany, France and Italy, describe how they combined observations at different wavelengths covering different spatial scales to build a model of the massive young stellar object (YSO) IRAS 13481-6124, which includes a massive central star, a dust disk heated by the central star, and a bipolar collimated outflow of molecular material, which is strongly indicative of ongoing accretion via a disk.

Using the near-infrared imager AMBER on ESO’s VLTI telescope – the interferometric mode offered by the array of 4 VLT unit telescopes and a number of smaller 1.8-m auxiliary telescopes – and the 3.5-m New Technology Telescope, they produced resolved images of 2 distinct components to the source. Combing their data processing and modelling, they identify these as a compact hot dusty disk that is being heated and slowly evaporated by the stellar radiation, surrounded by the extended remainder of the dense envelope from which the new star formed.

This is the second time in a few months that obervations with near-IR interferometry result in a Nature paper (see also the eps Aurigae paper in April) – a welcome sign perhaps that this technique is slowly coming into maturity and starting to produce good science. Interferometry, while long a staple in the radio astronomer’s toolbox, is really tough at shorter optical or infrared wavelengths, often requiring control of aberrations and deformations in the instruments to sub-micrometer scales. Converting the output from interferometric instruments to images or spectra also requires additional processing steps, complicating the data reduction procedures. If you’re interested in how that works, the gory details are described in the Supplementary information at Nature.

Is this the first ever detection of an accretion disk around a massive YSO? I don’t know everything that’s been published on the subject but I don’t think so. Several papers have been published in recent years with other kinds of disk detections that seem pretty conclusive to me, e.g. Davies et al’s paper of last year using integral field spectroscopy, showing clear signs of a rotating disk-like structure around the massive YSO W33A – so we had a good idea that they were there. But as for an actual image of such a disk, well, I guess Kraus et al may now take that prize.

Interestingly, Kraus et al fitted the observed characteristics of the disk with the analytical relations that low-mass YSO disks are observed to follow. They find that the disk of IRAS 13481-6124 is consistent with these same relations. This result suggests that the process of massive star formation is perhaps not as fundamentally different from “regular” low-mass star birth as astronomers thought, and give a nice vote of confidence to our currently accepted models of star formation.

A model that works: isn’t that nice for a change?

References

Kraus S, Hofmann KH, Menten KM, Schertl D, Weigelt G, Wyrowski F, Meilland A, Perraut K, Petrov R, Robbe-Dubois S, Schilke P, & Testi L (2010). A hot compact dust disk around a massive young stellar object. Nature, 466 (7304), 339-42 PMID: 20631793

Krumholz MR, Klein RI, McKee CF, Offner SS, & Cunningham AJ (2009). The formation of massive star systems by accretion. Science (New York, N.Y.), 323 (5915), 754-7 PMID: 19150809

Davies B et al (2009). The circumstellar disk, envelope, and bi-polar outflow of the Massive Young Stellar Object W33A. MNRAS, Vol. 402, Issue 3, pp. 1504-1515. (arxiv)

Image: Kraus et al (2010)