Star formation loves infrared dark clouds
We all know and love Galaxy Zoo and the various Zooniverse projects that have sprung up in recent months – Solar Stormwatch and Moon Zoo to name a couple. And there’s more on the way. Since the start of the year I’ve been excited about getting involved in another Zooniverse startup, the yet to be named Project IX. Project IX will deal with an area of astronomy I’m particularly interested in, namely star formation.
Understanding how stars form, in the numbers, sizes and masses that we observe them all around us in the Galaxy, and how this process of star birth affects our Galaxy as a whole, are very fundamental astrophysical questions. Stars are the factories of the Universe: light elements are fused in each and every stellar core into heavier stuff – even into dust and ash as it nears the end of its lifetime. Stellar death then returns these new materials to the medium that surrounds it, either gently drifting away as the star loses its hold on the outer layers of its atmosphere, or ripping violently through space in a supernova explosion that is visible across the Universe.
Looking back at star formation in high-redshift galaxies has proven to be a very interesting field of study: do galaxies form stars continuously, or in bursts? What triggers it, and what makes it stop?
As we can’t resolve individual regions where stars are forming in the distant Universe, we look for spectral markers – light signatures that we know are signposts for star formation – and try to understand what’s happening simply by inference. To learn how these markers relate to real physical properties, our own Galaxy is an invaluable laboratory. Futhermore, it’s becoming increasingly clear that the formation of planets is a natural and common consequence of star birth, rather than some odd anomaly. We can’t hope to understand how planets form without knowing how their stellar host does, and vice versa.
Star formation takes place in dark nooks and crannies, mainly in our galactic disk, where material is densest. Not much visible light is emitted from these cold corners, and dust keeps the young star hidden while it accretes more matter. In the infrared, however, these cold spots can radiate quite brightly, and the infrared Spitzer Space Telescope has in recent years made a huge contribution to our understanding of star formation processes. And while Spitzer’s fuel for keeping the instrument cold ran out some time ago, we’re nowhere near done with extracting new information from its data.
For Project IX, we’re taking images from a large Spitzer imaging survey called GLIMPSE, and identifying a number of areas related to star formation that zooites can help in. These images are scientifically as well as visually stunning, so we’re pretty sure we can convince lots of people to donate their time to examine them and tell us what they see. Are you in? To get a taster, images from GLIMPSE and its companion survey MIPSGAL are on display here.
Rob, who is co-ordinating Project IX at Zooniverse Towers, also had the idea of opening up the process of how a Zooniverse project comes about up to the public. So he and Chris have been blogging about the project on the Zooniverse site. I’m really excited about being part of Project IX and am looking forward to it coming together – and all of us involved are licking our chops and sharpening our pencils for the great science we can do with the data. More to come!
]]>
(click to enlarge)
The Hertzsprung-Russell diagram is one of the fundamental plots in astronomy. I remember it being one of the very first “sciencey” things I learnt about astronomy. It’s a very elegant plot, as it relates two very basic quantities about stars, their temperature and their brightness, and presents a visually memorable picture. The main known classes of stars each, like white dwarfs or red giants, populate their own corner of the diagram.
And now Stuart has taken the HR diagram and made a human version of it: the Astronomer HR diagram! It’s very neat, and lots of astronomers have been figuring out where they would place on the plot. If I count my SPIE Proceedings papers, not strictly refereed but usually counted as such for intrumentalists, I’m at [17,4500], nicely along the Main Sequence. Counting just my very strictly peer-reviewed papers, I’m at [3,4500], in the new media section. Either’s fine by me!
Image: S. Lowe
]]>
Route of the Sea of Cortez expedition
John Steinbeck won the Nobel Prize for Literature in 1962, and though his popularity had waned in the latter stages of his career, he’s been a much-read and well-loved author for many decades. The Nobel committee cited his “sympathetic humour and keen social perception” as the hallmarks of his writing. Steinbeck’s books and stories often deal with war, class, adversity and destitution, and in his lifetime he wrote both fiction and non-fiction; the former frequently based on his real-life experiences as a journalist. But did you know Steinbeck also wrote about science?
On my recent holiday to the central coast of California, I read Steinbeck’s The Log from the Sea of Cortez
The book contains a fair bit of barnacle-talk but is mainly a platform for Steinbeck’s views on life, the world, politics, and science. It’s really excellent and I’d recommend it to anyone who’s into any or all of those topics. Importantly, he actually manages to interweave all these subjects that cast a new light on old questions: what is science, why do science. He talks about relativity, causality and destiny.
The start of the book contains a lot of discussion on the reason for undertaking the trip, and the reason people do science in the first place.
“The design of a book is the pattern of a reality controlled and shaped by the mind of the writer. This is completely understood about poetry or fiction, but it is too seldom realized about books of fact. And yet the impulse which drives a man to poetry will send another man into the tide pools and force him to try to report what he finds there. Why is an expedition to Tibet undertaken, or a sea bottom dredged? Why do men, sitting at the microscope, examine the calcareous plates of a sea-cucumber, and, finding a new arrangement and number, feel an exaltation and give the new species a name, and write about it possessively? It would be good to know the impulse truly, not to be confused by the “services to science” platitudes or the other little mazes into which we entice our minds [...]“
In his initial discussion on the preparations for the trip, he comments on the subjectivity of science research:
“There is a curious idea among unscientific men that in scientific writing there is a common plateau of perfectionism. Nothing could be more untrue. The reports of biologists are the measure, not of the science, but of the men themselves. There are as few scientific giants as any other kind.”
“We wanted to see everything our eyes would accommodate, to think what we could, and, out of our seeing and thinking, to build some kind of structure in modeled imitation of the observed reality. We knew that what we would see and record and construct would be warped, as all knowledge patterns are warped, first, by the collective pressure and stream of our time and race, second by the thrust of our individual personalities. But knowing this, we might not fall into too many holes—we might maintain some balance between our warp and the separate thing, the external reality [...] We knew that what seemed to us true could be only relatively true anyway. There is no other kind of observation.”
The conflict between science and religion is one of the most divisive in the philosophy of science, and indeed in the political arena, today. Steinbeck, 60 years ago, posits that both are driven by the same search for one-ness with and understanding of the world.
“[...] it is a strange thing that most of the feeling we call religious, most of the mystical outcrying which is one of the most prized and used and desired reactions of our species, is really the understanding and the attempt to say that man is related to the whole thing, related inextricably to all reality, known and unknowable. This is a simple thing to say, but the profound feeling of it made a Jesus, a St. Augustine, a St. Francis, a Roger Bacon, a Charles Darwin, and an Einstein. Each of them in his own tempo and with his own voice discovered and reaffirmed with astonishment the knowledge that all things are one thing and that one thing is all things—plankton, a shimmering phosphorescence on the sea and the spinning planets and an expanding universe, all bound together by the elastic string of time. It is advisable to look from the tide pool to the stars and then back to the tide pool again.”
The “elastic string of time” is a recurring theme, both in scientific and general existential context. Steinbeck comments frequently that the Indians the group encounter in the Mexican coastal towns seem to live by an entirely different clock than the rest of the world (or at least the US); and on the boat time runs differently still. He uses this as a starting point for discussing aspects of relativity, both as a concept, and as a physical process in the Universe.
“It is strange how the time sense changes with different peoples. The Indians [...] had a different time sense -”time-world” would be the better term- from ours. And we think we can never get into them unless we can invade that time-world, for this expanding time seems to trail an expanding universe, or perhaps to lead it. One considers the durations indicated in geology, in paleontology, and, thinking out of our time-world with its duration between time-stone and time-stone, says, “What an incredible interval!”. Then, when one struggles to build some picture of astro-physical time, he is faced with a light-year, a thought-deranging duration unless the relativity of all things intervenes and time expands and contracts, matching itself relatively to the pulsings of a relative universe.”
Interesting how he makes the mistake of equating a light-year with time rather than distance, I wonder why? Maybe a PhD thesis resides in a library somewhere in the world providing an explanation. He talks at length about “the strictures of the old teleologies” – the idea that processes have an intrinsic goal – “that infect our observation, causal thinking warped by hope”, that result in our abhorrence of the statement that “a thing is because it is”.
The political backdrop of the time also features in Steinbeck’s writing. As the group embarked on their trip, Europe was descending into the anarchy of World War II. Yet, he writes,
“Hitler marched into Denmark and into Norway, France had fallen, the Maginot Line was lost—we didn’t know it, but we knew the daily [sardine] catch of every boat within four hundred miles. It was simply a directional thing; a man has only so much. And so it was with the chartering of a boat. The owners were not distrustful of us; they didn’t even listen to us because they couldn’t quite believe we existed. We were obviously ridiculous.”
The war features heavily in many of Steinbeck’s books, inluding in Cortez, albeit in a more subtly unsettling way as the expedition was unaware of the events that occurred during their trip (and the US was at that point not yet involved in WWII). In addition, the quote to me emphasises something that is often forgotten or misunderstood when we talk about educationng “the public” about science. There’s a lot more to it than telling them about new discoveries, or showing them role models. There’s a lot of people who don’t quite believe that we exist – fiddling with pixels, containing information from outer space, for months on end, and claiming that somehow it should matter to them? That’s not to say we shouldn’t try to engage with these people, we just need a very different approach to those we use to entice the typical Guardian reader.
The book is packed with fascinating insights, and just overall great Steinbeckiness. It’s also a very funny book.
Next to marriage settlement or sentence of death, a ship’s charter is as portentous a document as has ever been written. Penalties are set down against both parties, and if on some morning the rising sun should find your ship in the middle of the Mojave Desert you have only to look again at the charter to find the blame assigned and the penalty indicated.
The outboard motor, the Hansen Sea-Cow, in particular is a comic thread throughout the book.
Our Hansen Sea-Cow was not only a living thing but a mean, irritable, contemptible, vengeful, mischievous, hateful living thing. [...] When and where these ghoulish little motors learn to reproduce themselves the human species is doomed. For their hatred of us is so great that they will wait and plan and organize and one night, in a roar of little exhausts, they will wipe us out.[...] It is more than a species. It is a whole redefinition of life.[...] It loved no one, trusted no one. It had no friends.
The Sea-Cow did not run that day but it seemed to enjoy having its flywheel spun.
Anyway, there’s far too much to talk about for me to sum up in this post. Just go read it.
Some asides….
In 2006, during my first trip to central California, I took a little pilgrimage to the Steinbeck Center in his birthplace, Salinas. It’s an odd appearance in a rather uninspiring town (sorry, Salinas) that you probably would never stop off in for any other reason, unless you needed a tractor, or some lettuce. I was the only visitor there for the whole duration of my visit, but the staff were lovely and the exhibits were actually very interesting. So if you enjoy reading Steinbeck or are interested in the socio-political and economic history of the US in the mid-20th century, it’s worth a visit.
The Steinbeck Center is currently holding an essay writing competition inspired by Steinbeck’s Travels with Charley, where he talks about his trip around the United States, late in his life, with his poodle Charley. A wonderful book. So if you’ve recently travelled with your dog, and feel inspired, write about it. Details here.
In 2004, scientists from the Hopkins Marine station in Monterey and the Instituto Nacional de Ecologia in Mexico recreated Steinbeck and Ricketts’ expedition to the Sea of Cortez as an educational project. Read about it here.
]]>
Bit of a holiday, back in a few weeks. Meanwhile, enjoy the first all-sky map released from cosmic microwave background satellite Planck!
]]>
Outreach and education are two areas that stand to gain from developments in semantic astronomy and an increased scientific presence on the web. Big changes have already taken place, driven by a community eager to connect and communicate about the research we do every day. As part of a panel at the AstroInformatics 2010 conference last week, I gave a talk on aspects of science communication and education that are benefiting from the semantic web.
The internet these days is a cacophony of conversations, opinions, visual information (and porn). Many scientists and science enthusiasts write about the stuff that inspires or excites them in blogs, like I do here, which allow them to connect to people they would never have encountered, let alone talked with, in real life. This has led to some great scientific content generated entirely by the science community itself, without intermediate brokerage by communication or media professionals. But in this symphony of chaos, how do we increase the signal to noise? How do we ensure that the best content is heard?
A number of initiatives have emerged to collate “good” scientific content, and in my talk I highlighted a number of them. Researchblogging, which I subscribe to and have talked about before, is a service that aggregates online content from blogs about peer-reviewed scientific research, and categorises it in subjects.I think this is a great project for two reasons: for scientists themselves it’s very interesting to see what colleagues outside of our immediate realms are saying about new research – like an online journal club; second, for science enthusiasts the site is a place to read about new work, often in a more critical way than is reported in the media, with links back to the original publication. In similar fashion, The Guardian have recently introduced a new method of science reporting called Story Tracker, where a science story is augmented with additional content submitted to the paper with the aim of giving a balanced picture of what people are saying about the research, rather than just PR companies.
While Story Tracker still relies heavily on human curation of information, ResearchBlogging makes use of tagging and links (=semantics) to gather and organise content. But given the terse relations between the “mainstream” and “new” media, The Guardian’s willingness to experiment with new models of reporting is great, and I’m interested in seeing how the experiment evolves.
But how much of these dialogues actually reach broader audiences than traditional science communication methods? How many people have developed a passion for astronomy from reading blogs, or seeing photos on Flickr? Gordon Squires of IPAC spoke about “futility tweets”, and the difficulties in reaching a truly large audience. He suggests we get celebrities to help promote our message (as IPAC did). That’s certainly a good point, but what about those of us who don’t work in Los Angeles? Every community has its celebrities, he reckons, and we need to get them on board.
Citizen science projects like Galaxy Zoo have been immensely successful in generating an active discussion and pulling in crowds to help with scientific research. A survey of zooites showed that many of them are motivated simply by the desire to contribute to scientific research. The success of Galaxy Zoo alone is entirely based on the principle of open access to data from astronomical surveys, and the project has spawned a whole new organisation, Zooniverse, to continue tapping the power of a crowd for the benefit of science.
In an article published in the Journal of Science Communication earlier this year, legal scholar Victoria Stodden examines the policy framework required to safeguard this access to science by citizens, and taking it further, how to enable a progression from scientist-led citizen science to citizen-led science. With both the data and the software readily available for download, what is required to empower ordinary citizens to go and explore for themselves?
“Access” was the theme for Gus Muench’s talk [pdf] in the session – not just access to data, but also access to people.This is where efforts like the 365 Days of Astronomy podcast series, or the Pub Astronomy videos, come in. They are about astronomers and astronomy lovers giving up their time to talk about what fascinates them, and about why they do what they do every day. That too is important in engaging with the public.
One of my final slides was a plug for the .Astronomy workshops, of which we’ve now had two instalments – Cardiff 2008 and Leiden 2009. At least for me, .Astronomy was about bringing together people who are active in any kind of astronomy-related project that uses the new opportunities offered by the social or semantic web. After the first workshop it seemed apparent that many people had projects or ideas going on, some as part of their daily jobs, others simply as hobbies. With the workshops, we wanted to create a community and foster collaborations between these folks, to really exploit these new technologies to the full. While many of the projects are small in scale, they may well be building blocks for bigger things to come.
The web is enabling us to move from “public outreach” to “public engagement”; from a one way street, a cul de sac even, to two-way traffic. There is much to be gained from this for all involved. Public engagement, Simon Jenkins, is not about asking for more money. It’s about exploiting to the full the new and exciting directions our technological society is naturally evolving in to push the boundaries of knowledge about life and the world we live in.
References
Victoria Stodden (2010). Open science: policy implications for the evolving phenomenon of user-led scientific innovation JCOM, 9 (1)
The video + slides of the entire session is here.
]]>
Optical layout of LSST, the catalyst for many semantic headaches
Like many sciences, astronomy is becoming increasingly data-rich. The next generation of observatories, such as the Large Synoptic Survey Telescope, will produce staggering amounts of data every night and push the subject into the petabyte regime. The large surveys that feed a substantial portion of the research community today, such as the Sloan Digital Sky Survey, are already demonstrating the difficulties of converting large datasets into knowledge: converting the data into catalogues, estimating selection biases and performing robust statistics are all common problems to those working with the data. Astroinformatics, or the science behind the information captured in our wealth of astronomical data, is therefore becoming an increasingly relevant field of study. The AstroInformatics 2010 conference was organised with the aim of essentially defining this emerging field.
Given that the number of astronomers in the world is unlikely to increase at the same rate as our data volumes, the key to continuing our current rate of discovery is information. The only way to mine large datasets successfully is to have sufficient meta-data provided alongside it to judge its content and value. In astronomy we actually do this very well already with our standard FITS format for images and tables. Introduced as a standard in 1981, FITS files are accompanied by standardised text headers containing much of the provenance of the data. But for the flood of data that’s about to be produced in the next few years, something altogether more sophisticated will be required, and that’s where semantic astronomy will come in.
With semantic astronomy, we essentially want to capture all the information that humans can extract from a dataset in a machine-readable form. In a way, this just like the tagging and trackbacks we perform on social networking sites and blogs, like this one. But to formalise and standardise this to be able to compare and cross-match data from different sources or epochs, this requires the definition of ontologies. We spent a whole day at the conference discussing the developments in the semantic web, or web 3.0, and ontologies, drawing parallels between the web at large and the needs of astronomy in particular. These discussions veered off into a level of abstraction that was a little out of my understanding – but the ideas are very stimulating and well worth thinking about.
David Hogg of NYU gave an excellent provocative talk questioning everything we hold dear about metadata and semantics. “Semantic astronomy is doomed,” [pdf] he says, arguing that catalogs are essentially just meta-data – and that meta-data is all just interpretation rather than fact. So rather than the kind of cataloguing we do today to characterise our datasets, we need a probabilistic approach to meta-data. While his assertions make my head spin, I do think he makes some good points. Even with the best software for data discovery and the best catalogs, how do we ensure that the best data do indeed rise to the top? This takes us into search engine territory.
The development of a solid data mining infrastructure has so far resulted in the Virtual Observatory, a kind of super-repository that provides links to data sources with a high level of standardisation that allows astronomers to search for and work with data via well-defined protocols. Several software packages have been developed using the VO protocols with varying levels of uptake in the community.
I recently attended a VO workshop in Groningen, and by working through the example science cases it was obvious that some of the packages, like TOPCAT, offer excellent added value over currently available tools, whereas others were variations on existing themes. There were a lot of calls at AstroInformatics for an improved user friendliness of this software, but personally I think it’s simply the functionality that’s key. Astronomers’ time is valuable, and we don’t want to spend a month getting to grips with a new software tool unless it does something that we need much better than our current tool of choice. Why else would we love linux so much?
Very interesting were also the talks on what’s going on with semantics in some of our favourite search tools in astronomy: ADS for literature searches, and CDS and NED for data discovery. These services too are experimenting heavily with the new opportunities offered by the social web. Simbad, CDS’ database of astronomical objects, in March started allowing annotations to object records, and the CDS folks are letting this happen with as little intervention or moderation as possible. After 100 days, 57 users have posted 333 annotations – although two thirds of those came from 4 “power users”. Amazingly, the system has received no spam. Sebastien Derriere (CDS)’s slides on this are available online here [pdf]. While the uptake of the CDS annotations service is relatively successful, other initiatives appear less attractive to the community.
Alberto Accomazzi’s talk on the curation of the bibliographic record showed [pdf] that despite the numerous new features offered by the journals, and many now having adopted a delayed open access model, the main mode of query of the literature via ADS is to look at the article’s pdf, rather than the interactive html version with access additional features. Since 2004 AASTeX offers authors the opportunity to mark their text up with tags such as \object{}, \dataset{} or \facility{}, which automatically produces machine readable annotations with the paper; however, the uptake of these features is very low. The vast majority of links from journal articles to data or object identifiers were manually extracted by the editors, rather than provided by the authors. So right now, curation is still crucial to the process.
All these developments form part of the research cycle that is becoming ever more integrated via the social and semantic web. This closer integration is absolutely required to enable us to continue our rate of discovery in astronomy amidst a deluge of data. Conferences like AstroInformatics are essential to bring this issue to the attention of the community, and to create a debate about strategies to tackle it. On the conference blog, there’s a discussion over some concrete lines of action we can take in the immediate future – go read and give your opinion.
Image: Todd Mason, Mason Productions Inc. / LSST Corporation
]]>
The AstroInformatics 2010 conference is currently going on at Caltech in Pasadena. There’s a substantial online presence, if you can’t attend but want to take part in the discussion, here’s some links!
- The conference programme is here (times in Pacific time!)
- Follow the talks on Ustream
- Track the tweets (hashtag #astroinfo2010)
- Join in the discussion on the blog
More to follow!
]]>
A few days ago, I posted this poll about the show The Big Bang Theory, asking the question if it was bad for science (and women). I closed the poll last night, the votes are in, you people have spoken. Here’s the final results from 58 votes – and thanks for voting, polls are fun!
Most of you don’t seem to take sitcoms all that seriously, and that’s probably a sensible attitude. Also, quite a few of you think I should get a life. That’s probably also a fair statement. Beyond that, there’s about twice the number of BBT-lovers as there are BBT-haters, with a smattering of on-the-fencers. Well, you already know where I stand, but before I return back to the life that I do in fact have, let me elaborate.
Like I said in the previous post, I really love BBT. One of the reasons I don’t have a problem with the way the characters are presented is that they have really evolved as the show’s progressed – particularly the central trio of Leonard, Penny and Sheldon. They are very human and loveable. The message to me is that every Sheldon needs a Penny in their life, and vice versa, which is lovely.The boys may mock Penny, but she often comes out on top. And even though Penny looks down on the scientists’ geekiness, she ends up joining in and having fun.
I suspect that many people who have a problem with the stereotyping haven’t watched beyond the first few episodes, in which the characters are very one-dimensional. And I guess the reason these folks didn’t continue watching is that they just didn’t like it, which would further contribute to their negative feeling about it.
I don’t actually think the show is perfect, there are some things that maybe I’d like to see changed. The two supporting characters of Howard and Raj are a little one-sided compared with Leonard, Penny and Sheldon, and I really hope something happens on that front. And what happened to Leslie Winkle, the resident girl physicist? It would be great if her part became more substantial again. I read somewhere that the writers just couldn’t get quality material for her on a regular basis – but I found her much more fun and interesting than, say, creepy Kripke, who seems to have become more of a fixture in the show. Try harder, writers, please?
One voter who went for the “trainwreck” option impressively demonstrated an evidence base to their concerns about BBT: a study from 2008 published in the Personality and Social Psychology Bulletin, looking at how sexist humour affects male attitudes towards women (also described here). In a couple experiments, the authors show how exposure to sexist humour makes men who already have sexist attitudes towards women act out more on their feelings, e.g. by being less likely to donate money to a women’s rights organisation, than if exposed to gender-neutral jokes or to just sexist statements (rather than jokes). The message is that joking about women makes sexist behaviour more acceptable. In the authors’ own words, “sexist humor acts as a releaser of prejudice”.
I think behavioural research of this kind is not hard science in the way that physics is, and I don’t know enough about the background and methodology of the study to analyse it critically. I’m sure there are some provisos, no research is perfect, but I can accept their conclusion that sexist jokes, like racist or homophobic jokes, can make it seem ok to discriminate, which is bad. I just don’t think BBT is as one-sided as that.
An interesting side avenue to the discussion was raised by another friend: perhaps our personal feelings about BBT say more about ourselves than about the show? Go think about that, voters.
Ford, T., Boxer, C., Armstrong, J., & Edel, J. (2007). More Than “Just a Joke”: The Prejudice-Releasing Function of Sexist Humor Personality and Social Psychology Bulletin, 34 (2), 159-170 DOI: 10.1177/0146167207310022
]]>