Archive for April, 2010

(Guest Post) The Emperor’s New Math

Posted in The Universe and Stuff with tags , on April 20, 2010 by telescoper

Time for another guest post from my old chum Anton, this time on the topic of mathematics. I’m not sure any mathematicians reading this piece will be too happy, but if that applies to you then blame him not me. As usual, comments are welcome through the proper channel at the bottom of the page..


Nowadays a page of mathematics looks to a physicist or engineer like gobbledygook. This was not always so: a century ago a physicist might hope to understand everything in journals of mathematics, and even contribute to them. Fifty years ago a physicist might not be able to understand everything written there, but the mathematics would appear comprehensible in principle. A qualitative change has since taken place.

This change has coincided, roughly, with acceptance of the distinction between ‘pure’ and ‘applied’ (impure??) mathematics, and with the consequent, deliberate, emancipation of ‘pure’ mathematics. This is a new departure: for centuries mathematics evolved side by side with physics, and the mathematics that was studied was the mathematics used in tackling physical problems. Galileo had said (in his work Il Saggiatore, The Assayer) that

…the universe… cannot be understood unless one first learns to comprehend the language… in which it is written. It is written in the language of mathematics.

So the change is recent, and it is huge. I suggest that it is a change for the worse; that in divorcing themselves from physical science pure mathematicians have cut off their air supply; and that the suffocating style of modern pure mathematics is a result. Mathematics was not born in a vacuum, and it will not ultimately flourish in one.

A pure mathematician might respond that I would say that, since I am a physicist. But perhaps an outsider is needed to see the problem; insiders generally adopt the party line. The justification for my stance is this. Mathematicians acknowledge that their subject is the formal study of patterns. And mathematicians think in patterns, not formulae – which are really a highly efficient way to express their thoughts. Crucially, the patterns arising in the natural world are far richer and more diverse than the patterns that even the best pure mathematicians can pull out of their heads by introspection. Even number theory is not an exception, for the positive integers are abstractions – ideals – of the physical realisations of one, two, three etc sheep in a field, or boats on a lake.

The role of pattern explains the “unreasonable effectiveness” of mathematics in physical science (as Eugene Wigner put it), since physics is concerned with relations – correlations – between variables in space and time, and correlation is synonymous with pattern. The theoretical physicist Lev Landau vehemently believed that the best mathematics is the mathematics used in physics. An opposing point of view was taken by the pure mathematician Paul Halmos, in an essay titled Applied Mathematics is Bad Mathematics. Not all mathematicians share Halmos’ view, however. The mathematician Morris Kline was the author of many books about mathematics and its embedding in the cultures which nurtured it. In his book Mathematics: The Loss of Certainty, Kline demonstrated that the history of mathematics in the 20th century has not been the smooth progression that it appears to the outsider; and that arguments about the foundations have led not to resolution, but to schism into differing schools – based on different foundations – that do not talk to each other. Mathematics is not in fact a one-way road running from self-evident axioms to consequences, but is open at both top and bottom.

Already in the 19th century a formal style was developing in the mathematical study of logic, and such distinguished noses as Henri Poincaré (in Science et Methodes, part II) protested as early as 1909 that this tended to hide misleading or negligible content. To no avail: the dominance of the formalistic logical viewpoint led to the adoption of its house style across the whole of mathematics. Below university level, mathematics is still taught today as it used to be, with the emphasis on the understanding of ideas rather than their formal presentation. Freshmen are often shocked when they first meet the new way of doing things, in university lectures given by professional mathematicians. I doubt that the form of modern mathematical writing is governed by its content, for whenever my research has demanded I read some contemporary mathematics, and I have had to translate a piece of modern mathematical writing into something comprehensible to scientists, I have found it difficult to distinguish substantial points from trivia. When, for instance, four axioms are needed to establish a result, they will typically be presented as having equal weight, even if one is the crucial axiom that allows most of the proof to be constructed, and another is used only in closing loopholes. Acknowledging the quality of axioms, as well as the quantity, does not compromise rigour.

When I think of the work of Andrew Wiles and Grigori Perelman, I realise that magnificent work is done today by mathematicians far beyond my own competence. But might mathematicians question whether what they regard as the only way to write mathematics is actually a convention, and not necessarily a good one? If they wrote mathematics as they did fifty years ago, others might be able to see for themselves. More fundamentally, might they also realise what their predecessors understood, that by its abstraction mathematics is given an autonomy of its own, and that to look to the physical world for inspiration is not to make mathematics a slave of physics? The present divorce between mathematics and physics impoverishes everyone.

The Easy Winners

Posted in Football, Music with tags , , on April 19, 2010 by telescoper

I’ve been a bit busy today so all I’ve got time to do is mark the news that by beating Plymouth Argyle, 2-0 away from home Newcastle United have won the Championship. In truth they only needed one point from their remaining three games to be sure of the title, but they passed the winning post in style with a comfortable victory that in fact condemns Plymouth to relegation. This may not mean very much to most readers of this blog, but I can assure you that being a Newcastle supporter is sometimes a thankless task and ‘m absolutely delighted to see the club return to the Premier League in such  a surprisingly convincing way.

I was thinking of posting a little bit of music to celebrate, and this sprang to mind. It’s my favourite Scott Joplin rag and it’s called – appropriately enough – The Easy Winners. It was written in 1901 and the original sheet music is decorated with pictures of sporting events. It is also one of the few rags that the composer himself recorded as a piano roll, although I have my doubts as to whether this is actually that version..

Life, the Universe, and Coloured Pencils

Posted in Biographical, The Universe and Stuff with tags , , on April 18, 2010 by telescoper

Yesterday’s post got me thinking about what it is that makes scientists decide on their own speciality. It’s got to have something to do with the intersection between interest and aptitude, in that I think we learn gradually through our time at School that there are some things we can do well and others that we can’t but the things we can do well aren’t always things we find sufficiently interesting to make a career doing.

I suspect luck also plays a big part, in that the choices one gets to make must be taken from the options at a very particular time. I ended up doing research in cosmology after my first degree, but it wasn’t any kind of a grand plan that got me to Sussex in 1985 to do that but it just seemed the best choice to me out of all the half-a-dozen other places I visited.

Before I meander off the point again I’ll just pass on something that one of my teachers at school told me, and which probably had a big effect on an impressionable teenager. It was my chemistry teacher, Geoff (“Doc”) Swinden, that probably had more influence than anyone in making me decide to become a physicist.

By the way he was called “Doc” because he had a PhD (or perhaps a DPhil, as I think  he got his doctorate, in organic chemistry, from Oxford University). I didn’t go into Organic Chemistry, of course, but that was mainly because I hated the practical aspects of chemistry and pose a considerable threat to the safety of others when placed in any kind of laboratory environment.

Anyway, I remember very well a comment of Doc Swinden’s to the effect that anyone wanting to be called a proper scientist should avoid any subject that required the use of coloured pencils. That ruled out biology, geology and a host of others and left me firmly in the domain of physical science. I ended up going to Cambridge to do a degree in Natural Sciences, which allowed me to do chemistry and physics for a year and then decide which to continue. Obviously I went the way of physics.

I don’t regret going into physics at all, but I don’t think this bit of advice was all good. When I went to Cambridge to study Natural Sciences, I had to pick an extra subject to do in the first year to do alongside my main choices, chemistry, physics and mathematics. Among the options were geology, biology of organisms, and biology of cells but, mindful of the possibility that all of these might require the dreaded coloured pencil, I went for a course called Crystalline Materials. It’s true that I didn’t have to colour anything in, but it was the most mind-numbingly awful course I’ve ever taken. I very nearly failed it at the end of the first year, in fact, but still managed to get  a First-class mark overall.

Going back to yesterday’s post, I realise that one of the reasons I’m less gung ho for Mars exploration than some of my colleagues might be that it’s a bit too much like geology or even biology. It seems the ghost of the coloured pencil is still haunting me.

To Mars or not to Mars?

Posted in Science Politics, The Universe and Stuff with tags , , , , , on April 17, 2010 by telescoper

Amongst  the news this week was President Obama’s announcement of a new space exploration policy for NASA. Out goes the Constellation program, including the Orion crewship, its Ares launch rocket, and the rest of the project’s Moon-bound architecture. Obama says NASA were on an unsustainable path, costing too much money and taking too long to develop. Instead he’s given them extra funds ($6 billion, modest by the standards of space exploration) and told them to find new ways of putting people into space. Obama’s particular goal is to send someone to Mars by the mid 2030s and return them safely to Earth. I think Obama’s plans have ruffled a few feathers, especially among those longing for a return to the Moon, but it seems to me to be both bold and intelligent. 

The European Space Agency also has a programme – called Aurora – which includes components involved with both robotic and human exploration. This programme is a kind of optional extra within the ESA budget and countries that wanted to join in were asked to pay an extra contribution. The UK opted in so now we pay a top-up on our subscription to ESA in order to participate. This will be one of the things that transfers to the new UK Space Agency, when it’s up and running properly, from the Science and Technology Facilities Council (STFC).

Thus far the UK policy has been not to get involved in human space exploration. There are a lot of reasons behind that, but one of the most important is sheer cost. Space exploration is expensive by its very nature, but involving human beings creates enormous extra costs connected with keeping them alive and keeping them safe while they are in space. Since our national expenditure on space exploration has largely been channelled through STFC (or its predecessor PPARC) where it has had to compete for funds with “pure” science activities in the areas of particle physics and astronomy (and, more recently, nuclear physics).

I think the scientific argument against funding human exploration has always been as follows. There aren’t many things that people could do on Mars that a robot couldn’t – here I’m talking just about scientific experiments and the like. Human space exploration is much more expensive than the robotic variety. The scientific value for money is consequently much higher for robotic missions ergo, since money is tight, we don’t do human space exploration. Plus, we couldn’t afford it anyway…

The other factor is that there aren’t many feasible targets for manned spaceflight in the first place. The Moon and Mars are basically it. Other objects in the solar system are either too distant or too inhospitable (or both) to be considered. Unmanned probes haven’t all been successful, but some certainly have paid off enormously in scientific terms. I give the Cassini-Huygens mission to Saturn (and its extraordinary moon Titan) as an example that has turned out, in my opinion, to be nothing short of sensational. The images of Titan’s surface sent back by Huygens were gobsmackingly amazing, for instance.

Before going on let me point out that I’m a cosmologist, not a planetary scientist. There’s a tendency among scientists to think that their own field is more important than the others with which it has to compete for funding. It’s perfectly natural that someone working on galaxy formation should find galaxies more interesting than planets, and vice-versa. We all pick what we want to work on, and obviously we pick what interests us most.  But any scientist worth his/her salt should have enough of a grasp of the big picture to recognize outstanding work in disciplines other than their own.  I don’t want anyone to think that the following comments are intended to suggest that there isn’t excellent work going on in the UK and rest of the world in the field of planetary exploration.

I do think, however, that there is a big difference in character between fundamental science (especially particle physics and cosmology) and planetary exploration. In fundamental physics we are attempting to uncover the nature of basic constituents of the universe and the general laws that govern the structure of matter and how it interacts and evolves – in other words, its scope is (or at least tries to be) universal. It’s certainly this aspect – trying to unravel an enormous cosmic puzzle – that drew me into cosmology. By contrast, the study of a particular planet – even a fascinating one, such as Saturn with all the beautiful orbital dynamics going on in its ring system – lacks this aspect of universality. That’s why cosmology interests me more than planetary exploration does. This is nothing more than a statement of personal interest.

Having said that – and pointing out  again that I’m no particular expert on the Solar System – I don’t find the Moon and Mars very  interesting from a scientific point of view compared with, say,  the outer planets which I find fascinating. Others – a great many others, in fact – obviously do see a lot of interest in Mars. I’m not at all convinced about the scientific merit of some other space probes either, especially the planned Mercury orbiter BepiColombo. But there we are. We can’t all expect to agree on everything. What I’m trying to say, though, is at the moment these different types of activity are funded from the same pot. In order to draw up an order of priority, STFC has to compare apples with oranges with predictably bizarre outcomes.

Moreover, space exploration – especially human space exploration – isn’t just about science. There are definite commercial opporunities in space, in both short and long term.  Space missions often  provide results that are fairly easily accessible to non-scientists, so has considerable popular appeal as well as inspiring young people to take up science and engineering subjects. It has immense cultural impact too, altering the way we think about ourselves and our place in the Universe. But these aren’t unique to space exploration. Particle physics and astronomy do this too.

 But the overriding factor is the politics. When NASA put a man on the Moon 40 years ago, it was never about science – it was a political statement made right at the height of the Cold War. We no longer have a Cold War, but nations still feel the need to show off to each other. It’s called national pride. Politicians know how this works, and how it can turn into votes…

So we shouldn’t think of the plan to put a man on Mars as being primarily a scientific thing anyway. I’m quite comfortable with that.  My worry – if the UK decides to take part in manned Mars exploration – is that the money will come from the already dwindling pot allocated to fundamental science. Particle physics and astronomy research in the UK is on the ropes after the recent devastating cuts. Any more blows like this and we’ll be on the floor. I’m deeply worried that far worse is already on the way – a combination of public spending cuts after the general election and political directives to devote more to space exploration.

The new UK Space Agency could be either a hero or a villain, and I don’t know how it will turn out. On the one hand, the creation of this organization may prevent the fundamental sciences from being squeezed further by expensive space projects. In this way it might represent a recognition of the different characteristics I talked about above. The industrial and commercial aspects of space exploration are present in the new outfit too.  On the other hand, the result of hiving off the “glamorous” space parts of STFC may lead to further cuts in what is left behind. I’m also nervous about the future relationship between UKSA and STFC, especially the extent to which the former can demand research grant funding from the latter.

I’m sorry this has been such a long and rambling post, but this has been on my mind for quite some time and I wanted at last to put something together about it. I could summarise what I’m saying as follows:

  •  I’m not convinced about the scientific case for Mars exploration – particularly if it involves manned missions
  • BUT it’s not my field so it’s not my decision to make
  • AND there’s more to Mars than science anyway
  • SO by all means do it if there’s a will
  • BUT for heavens sake don’t pay for it by killing off the rest of astronomy

This is something that I’d be genuinely interested in hearing other views on. What is stated above is my opinion and is not intended to be representative of anyone, but I’d be very interested in hearing other views through the comments box.

Another rare event…

Posted in The Universe and Stuff with tags , on April 16, 2010 by telescoper

I was just thinking yesterday that it can’t often have happened that a scientific meeting has been curtailed by a volcano, at least not in Britain, when I see another rare event took place earlier in the week in America.

I’m just glad that Howard County (Is this right? Ed.) was there to record this fireball, although I think that’s quite a strange name for a policeman … (You’re fired. Ed.)

Ash Thursday

Posted in Science Politics with tags , , on April 15, 2010 by telescoper

I couldn’t resist putting up a quick post about the bizarre circumstances that have seen all airports closed and planes grounded all around Britain,  and the  skies emptied of aircraft.  The eruption of a volcano in a part of Iceland called Eyjafjallajoekull – there will be a pronunciation test at the end – has led to considerable plume of ash being thrown up into the atmosphere. Prevailing winds being roughly south-easterly in direction, part of this cloud has been heading towards mainland Britain.

You can see the cloud as the dark brown and black region on the following satellite image taken early this morning.

Apparently the ash contained in this cloud poses a significant danger to aircraft engines, so the UK Air Traffic Control system decided during the course of today to close UK airspace to all incoming and outgoing flights. Cue travel chaos.

It is anticipated that the ash will affect all of Britain by about 1800 GMT (i.e. 1900 British Summer Time) . It will dissipate as it spreads but of course as long as the eruption continues more ash will be pumped into the air.

One of the events disrupted by this display of vulcanism is the UK National Astronomy Meeting currently taking place in Glasgow. Many UK participants travelled to this meeting by plane and some of them are stuck there now because their return flights are not flying. NAM usually tends to be the sort of thing that senior academics tend to attend for only a day or two because the specialist sessions are quite brief and there are so many other things to do.

Today (Thursday) there was meant to be a Panel meeting organized by the Royal Astronomical Society at which members of the Science and Technology Facilities Council Executive, among others, were supposed to face questions from the assembled throng of astronomers. UK Astronomy has been under a dark threatening cloud for quite a while already, even before the Icelandic volcano did its thing.

However, the panel discussion was drastically curtailed by some not being able to make it to Glasgow and others having to leave early in order to get the train because their planes had been cancelled. In fact, according to what I’ve gleaned from the extensive Twitter traffic (from #NAM2010), John Womersley (Director of Science Programmes at STFC) was basically holding the fort in the absence of the other pundits. He seems to have come in for quite a lot of flak from younger scientists, particularly those whose careers have been wrecked by decisions made by the STFC Executive. I suspect those unable to make it are probably not ungrateful at being presented with an excuse for their absence.

Fellow blogger Andrew Jaffe was commendably prescient in deciding well in advance to return to London from Glasgow by train rather than plane. That’s the kind of  decision many people live to regret given the legendary unreliability of our train network, but this time it certainly paid off.

Not so many Cardiff astronomers went to NAM this year – the reason being that we are back to teaching while most other UK universities are still in their Easter break. However, those Cardiff staff and students who have gone there face more than a few problems getting back!

The meeting is scheduled to end tomorrow but it’s very unclear whether the skies will be open by then. We might have a few cancelled lectures if the situation doesn’t improve quickly…

General Purpose Election Blog Post

Posted in Bad Statistics, Politics with tags , , on April 14, 2010 by telescoper

A dramatic new <insert name of polling organization, e.g. GALLUP> opinion poll has revealed that the <insert name of political party> lead over <insert name of political party> has WIDENED/SHRUNK/NOT CHANGED dramatically. This almost certainly means a <insert name of political party> victory or a hung parliament. This contrasts with a recent <insert name of polling organization, e.g. YOUGOV> poll which showed that the <insert name of political party> lead had WIDENED/SHRUNK/NOT CHANGED which almost certainly meant a <insert name of political party> victory or a hung parliament.

Political observers were quick to point out that we shouldn’t read too much into this poll, as tomorrow’s <insert name of polling organization> poll shows the <insert name of political party> lead over <insert name of political party> has WIDENED/SHRUNK/NOT CHANGED dramatically, almost certainly meaning a <insert name of political party> victory or a hung parliament.

(adapted, without permission, from Private Eye)

Our New Chief Scientific Advisor …

Posted in Science Politics with tags , , , , on April 14, 2010 by telescoper

I just came across an interesting bit of news that I thought I’d share with those of you who haven’t heard it already. It came out some time ago, in fact, but I  missed it at the time.

Over a year ago I went to a meeting about Science Policy in Wales. One of the issues raised at that meeting was that the Welsh Assembly Government hadn’t yet managed to appoint a Chief Scientific Advisor, despite the results of a review in carried out in 2008 by Sir Christopher Pollock that argued strongly that this should be done. In June 2009, the (new) First Minister Carwyn Jones finally announced that he would proceed with an appointment to this new position but it’s still taken quite a while to get someone to fill the post.

Still, better late than never, and we now know who it is who will advise the WAG on matters scientific. It turns out that the first ever Chief Scientific Advisor for Wales will be John Harries (left), who is originally from Aberavon, and is the University of London Professor of Earth Observation at the Blackett Laboratory of Imperial College London, who has previously been a senior adviser to the UK Government in several roles. Professor Harries will take up his role on May 1, but I think he’ll carry on working at Imperial about 20% of his time.

The Chief Scientific Adviser’s role will be to provide scientific advice to the First Minister and the Welsh Assembly Government, to promote science, technology, engineering and mathematics and the role of science within the wider knowledge economy.

First Minister Carwyn Jones said:

The appointment of Professor Harries as our first Chief Scientific Adviser for Wales will ensure that we build on an impressive track record of achievement, and develop a more effective promotion of science and technology within the wider knowledge economy arena.

This will prove invaluable as we continue to encourage the knowledge, skills and enterprise to strengthen businesses in Wales ahead of the global economic upturn.

According to Professor Harries,

It is a huge honour to be asked to become the first Chief Scientific Adviser for Wales and I look forward with great enthusiasm to carrying out this new role on behalf of the government and people of Wales.

Wales is a small country, but is capable of the intelligent application of new science and engineering as a basis for greater commercial success in industry. The role includes acting as Head of Profession, providing a focus for good practice and the enhancement and encouragement of scientists and engineers in Wales. This is a job that encompasses two (along with my family and rugby) of my great passions – Science and Wales. I will give it my very best effort.

The appointment of a physicist as Chief Scientific Advisor for Wales could be very interesting with regard to the future development of the subject within the Principality. In particular, the recent devastating cuts in the UK’s  astronomy funding have led to some of our astronomers wondering whether they should work on space instruments that look down rather than up, and a move into Earth observation might now be even more timely.

In more general terms, it’s good to see the Welsh Assembly recognizing the importance of science, although whether they see its importance  being connected very narrowly with commerce remains to be seen. Anyway, I think it could turn out to be an excellent move, and I want to take this opportunity to wish Professor Harries the best of luck  in his new job!

Another Day, Another Panel..

Posted in Science Politics with tags , , , on April 13, 2010 by telescoper

I’m completely knackered, and my dinner’s warming up, so I’ll keep this relatively brief…

I got up at 5am this morning to take the train  to London  in order to attend the first meeting of the STFC Astronomy Grants Panel (AGP) for this year. The deadline passed in early April, and the applications have now all been received by Swindon Office so now the AGP has to swing into action, like a well-oiled machine, to rank the applications and make recommendations as to which ones should receive funding.

This meeting was chaired by the new Astronomy Grants Supremo,  the e-astronomer (although on STFC business he uses his pseudonym, Andy Lawrence). The real hard work comes in a succession of meetings later in the year, but this one was basically in order for us newbies to learn the ropes and to get a bit of background before we get going. Actually, I’ve been on such panels before – I chaired the Astronomy Theory Panel a few years ago, before moving to Cardiff – but it’s all changed quite a lot and I’m actually glad  I had the chance to learn about the new procedures. It was nice to see the other people involved too, some of whom I didn’t know before and some of whom I’ve known for years (often from other panels). When you get older as an academic, life turns into a Succession of  Panels. Sigh. I wonder if there are Panels in the Afterlife?

The backdrop to this round was provided by the deep cuts in Astronomy research that emerged from last year’s STFC  Prioritisation Exercise. We heard a summary of the Financial Position that was shocking in its magnitude as well as depressing in its likely long-term effects. In 2008, STFC funded “new” 92 postdoctoral research positions across the UK making the total number of astronomy PDRAs at that time about 295 (a PDRA usually lasts three years). In 2009 the number of new positions dropped to 69, and projections suggest a  number of about 60 this year. This will put the number of astronomy PDRAs at about 180, just short of a 40% cut with respect to the 2008 number. Moreover, last year saw a significant reduction in the number of rolling grants by about a third, although many of these carried on at a reduced level as standard (3-year) grants. Projections suggest that current funding levels will see 70% of the UK’s rolling grants unrolled in this way; this figure is higher than for this round because of  short-term injection of cash from RCUK – the famous £14 Million – that ameliorated the cuts this year and the fact that this year’s grant funding had slightly more money in it than other years of the three-year cycle for historical reasons. A full report of last year’s grants round should be available on the STFC website soon.

UPDATE: It is there now.

Of course it remains to be seen what happens in practice, and how this compares with projections of this sort. I won’t be able to say much on this blog about the process from now on – for reasons of confidentiality – but I can assure everyone reading this that everyone on the AGP wants to fund excellent science and will do everything they can to make the system work in a way that achieves this in the fairest possible manner. It’s inevitable, though, that in these tough times some excellent research will not be supported. That’s the thing that makes these Panels so stressful.

Anyway, apart from my growing apprehension of the scale of the task in front of us, the trip to London was otherwise pleasant. A lovely train journey in the sunshine through the beautiful spring greenery of Wales and England was very relaxing, and I even got tomorrow’s lecture written on the way. The meeting took place in a cramped and stuffy room at the Royal Institute of British Architects, a building of such poor design that you might think RIBA would disown it. Come to think of it, no. It probably won an award. Crap buildings so often do.

Oh, and the caterers forgot to supply our lunch on time too. Eventually we got a few measly sandwiches at about 2pm. Not impressive. Still, the main meetings will all be in Swindon. What a delight.

The way home wasn’t such fun. One of the engines of the train conked out shortly after leaving Paddington so we couldn’t go at proper speed and I got back to Cardiff 20 minutes late. It was still sunny, though, and I’d just put some lovely new music on my iPod so I wasn’t too bothered.

Now my dinner’s ready. And this has been 700 words. That’s not particularly brief, even by my standards…

Protostars in the Rosette Nebula

Posted in The Universe and Stuff with tags , , , , , on April 13, 2010 by telescoper

Every now and again I remember that I should  pretend that this is an astronomy blog. A new press release from the European Space Agency just reminded me again, by unveiling a wonderful new Herschel image of part of the Rosette Nebula:

This isn’t really one for the cosmologists as it concerns a star-forming region in our own Galaxy. Herschel collects the infrared light given out by cool dust; this image is a three-colour composite made of wavelengths at 70 microns (blue), 160 microns (green) and 250 microns (red). It was made with observations from Herschel’s Photoconductor Array Camera and Spectrometer (PACS) and the Spectral and Photometric Imaging Receiver (SPIRE). The bright smudges are dusty cocoons containing massive protostars. The small spots near the centre of the image are lower mass protostars.

This is a wonderful demonstration of how Herschel is able to see massive objects – probably about ten times the mass of the Sun – previously hidden from view within the nebular dust. Studies such as this will help astronomers understand much better the processes by which stars form in regions such as this.

PS. If you want to know why this is called the Rosette Nebula, you need to see what the whole thing looks like in optical light: