First of all, an apology. This blog has been very quiet of late — I've been writing up my thesis and taking my final exams. But as of last Friday all that is finished and am now the proud owner of a (provisional) upper second class degree in physics from Imperial! I have also managed to move house, which you'll realise is no mean feat if you know how much of a hoarder I am.

Now to the exciting news. As of today this blog will have a new home on the brand new Scientific American Blog Network! Click here to go and read my introduction post now. I am really excited about the move and I hope you will head over there to check it out. There are a lot of really amazing bloggers joining the network and I'm honoured to have my blog amongst theirs. So go and read Bora's introduction to the network or . . . More

It may look like a static yellow ball from here, but in reality the Sun is alive with activity. Right now it is becoming more active each day as we get closer to the next solar maximum, which is expected to peak in July 2013. However, a couple of years ago it was quieter than it had been for nearly a century. It had very few sunspots and radiated very little energy. This variation is normal — the Sun goes through regular cycles where its activity and number of sunspots go up and then down again. What was unusual was the depth of this solar minimum.

Dibyendu Nandy, from the Indian Institute of Science Education and Research in West Bengal, and colleagues Andres Munoz-Jaramillo and Petrus Martens, from Montana State University, think they might have found the reason for this almost unprecedented solar calm.

Each solar cycle lasts roughly 11 years. After this time, its magnetic field flips over. After two cycles the magnetic field has flipped twice and it ends up back where it started. During these cycles the amo . . . More

You might not be able to tell from wherever you are reading this, but black holes in the distant universe just shrunk down to as little as a tenth of their previous size. This is not some cosmic disappearing act; a new analysis of supermassive black holes at the centres of active galactic nuclei has revealed that their masses were previously overestimated by up to a factor of ten. The paper was published in Nature last week.



Active galactic nuclei, or AGN, are among the most luminous objects in the universe and are powered by massive black holes millions of times the mass of the Sun. Gas clouds, known as “broad line regions” for reasons that will become clear later, surround the black holes. These gas clouds range from a few light daysto hundreds of light days across; they are much wider than our solar system. Astronomers have been studying these clouds for over thirty years, but had not worked out the why some of them were flatter than others — until now.

. . . More

Galaxy clusters are some of the largest structures in the universe. Astronomers have found these clusters, which are large groups of galaxies bound together by gravity, as far back as only 4 billion years after the Big Bang (less than a third of the age of the universe). They know they contain stars that formed even earlier than that. But nobody had caught a cluster while it was still forming — until now.

Astronomers have found a “protocluster” that was around only 1 billion years after the Big Bang (that’s a redshift of 5.3 for anyone that’s counting). It sits in a region that is 40 million light years across and is rich in young stars.

The protocluster was found in data from the Cosmological Evolution Survey, COSMOS. COSMOS uses the Hubble, Spitzer and Chandra space telescopes with the ground based Keck Observatory and Japan’s Subaru Telescope to get an good look at the universe. COSMOS looks at a tiny region of sp . . . More

Last week astronomers working on the European Space Agency’s Planck experiment convened in Paris to talk about their first results, and they weren’t short of things to say. No less than 25 papers were announced on Tuesday 11th January — and this is before work has even started on the mission’s main aim of putting together a detailed picture of the Cosmic Microwave Background, or CMB.

The CMB is a uniform glow of microwave radiation, with only tiny fluctuations, that gives us a snapshot of the universe around 380,000 years after the Big Bang. We’ve seen it before, courtesy of WMAP in 2003 and COBE in 1992. But Planck has the power to look at this faint glow in never-before-seen detail, revealing more about the universe than every before.





Video showing locations of the different compact objects found by Planck.

Before they can get to work on this new view of the CMB, however, astronomers must study the foreground noise of the picture in detail. This “noise” is made up of structures formed after the CMB: galaxies, galaxy clusters, and matter within the Milky Way, such as gas and dust.

Planck astronomers studi . . . More

It’s not a question you’re likely to have ever considered, but the source of “food” for some of the most active black holes has been a longstanding line of inquiry for the astrophysics community. Many thought they had the answer when several studies seemed to show a link between collisions of similarly sized galaxies and the formation of a very active black hole at the centre of the merged galaxy. But a new survey of 1400 galaxies has answered the question once and for all and it turns out that, in most cases, this link doesn’t actually exist.It’s long been known that at the centre of most galaxies lies a black hole. Some are relatively quiet, like the one in our own galaxy, but others manage to take in some of the matter that surrounds them and then spit it out in the form of huge amounts of energy. There’s a name for what’s created by the most lively ones: Active Galactic Nuclei, or AGN for short. Scientists don’t quite understand why some black holes in galaxies are more active than others, but research done last year by NASA’s Chandra X-ray Observatory did . . . More

I have a post up on the Scientific American Guest Blog today. It's all about strange exoplanet discoveries, and what they can tell us about our own solar system. I really enjoyed researching and writing it, so I hope you'll enjoy reading it too...

"Habitable and not-so-habitable exoplanets: how the latter can tell us more about our origins than the former"





Beta Pictoris and its planet

The image above is of one of the planets I talk about, and its star. It's called Beta Pictoris b and is only around 60 light years from Earth. You'll have to go read my post to find out what's unusual about it, though.

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I've been really busy recently, so this post is a little shorter than usual, but hopefully just as sweet.

*

From far away Saturn’s rings look pretty solid – I’m sure I’m not the only person who, as a child, imagined it’d be possible to skate around the planet on them. In reality, though, they’re made up of millions and millions of bits of ice and dust, ranging in size from micrometres to metres. Until recently, scientists thought that the occasionally odd behaviour of the most massive ring, known as the B ring, was solely due to the pull of one of Saturn’s moons, Mimas. However, new research published in the December issue of the Astronomical Journal explains that Mimas is not the only reason for the variations that we see in this ring…



Joseph Spitale and Carolyn Porco from the Space Science Institute at Boulder, Colorado looked at four years worth of images of Saturn’s rings from the Cassini mission. They saw evidence of wave patterns in the B ring that seemed to have arisen spontaneously – without being forced by Mimas. The waves are thought to come about because of the high density of the B ring, and are given a boost by its sharp edge which reflects a . . . More

When we look up into the sky at night, we see stars (even in London I can usually spot a few!). But there haven’t always been stars and galaxies in the universe. In a period known as the dark ages – not to be confused with the other dark ages – there was no light at all. After the the ionised gas that filled the universe in its very early life cleared, there was a very long period of, well, nothing. The universe was transparent, but contained no stars or galaxies for just less than 400 million years. The process that allowed stars and galaxies to eventually form is known as reionisation, and new research published in Nature last month details a discovery that may open a new window on to this time.



In the paper, Lehnert and colleagues reported detecting the most distant object physicists have ever seen: a galaxy, the light from which was emitted less than 600 million years after the Big Bang. It’s the first galaxy known to have lived fully within the epoch of reionisation.

The galaxy, which goes by the catchy name UDFy-38135539, has a redshift* of z = 8.6 – the highest ever observed – and it was from this that the team were able to calculate the galaxy’s age. UDFy-38135539 was first spotted b . . . More

Depending on how you look at the question, "this", for me, could refer to several things.

If we're talking literally, "this" is sitting here and typing this blog post. If I weren't doing this there's a load of different things I could be doing at this moment in time. I could be writing the literature review for my project (due in less than a week - I've written what seems like a million plans and spider diagrams, but only one sentence so far). I could be preparing to start new lecture courses by revising old material, or acquainting myself with some introductory material for the new courses. Or I could be wasting my day watching old episodes of Come Dine With Me on 4oD. (I'll leave it as an exercise for the reader to determine which of those is most likely).

Take the question as it was intended and "this" would probably mean my degree. What would I be doing if I weren't studying physics at Imperial? Well, chances are I'd still be at university. Maybe, I'd still be at Imperial, studying a different subject - I always did fancy myself a bit of a fossil hunter, so perhaps I would have been equally as happy in the Earth Sciences department, studying roc . . . More

A couple of weeks ago I was at my mum’s house when she asked me to explain the concept of dark matter to her. I did, to the best of my ability, but her request got me thinking: stories about scientific research don’t always have a full explanation of the concepts in question, for good reasons, but maybe it would be good to have something to link to that does explain concepts in a bit more detail?

So I decided to write this post, as a kind of experiment. It is intended to be a brief* introduction to dark matter, for my mum and anyone else that would like a bit more background information.

In 1937, a physicist called Fritz Zwicky worked out the mass of the Coma galaxy cluster and noticed that it did not match up with the amount of light coming from it. In fact, he’d worked out that there was a lot more mass in the galaxy cluster than its radiated light would suggest. This missing mass is what we now call “dark matter”, and it makes up 23% of the mass-energy density of the observable universe and around 90% of the total . . . More

I thought I’d write about some of the things I’ve discovered since moving from a small town to the big city. It’s in list form because, well, lists are easy and I have a lot to do before I go and (hopefully) meet with my supervisor next week. I ended up writing quite a bit more than I planned to. Sorry about that.

Before I moved to London, I wish someone had told me:

1. You can get away with doing the bare minimum amount of work during the first two terms and then moving into the library for the third. However, this gets harder and harder each year, and really – who is benefitting from this arrangement? Apart from the Library café who end up with all your money because you no longer have time to cook for yourself, and need energy drinks and coffee to stay awake long enough to cram everything in.

I’m terrible for leaving stuff to the last minute, so I’ve done this little routine for the past three years. Every year I say I’ll change, and every year I do the same thing again… this year I’m going to change for real though, promise.



2. Following on from the first point: Physics is a lot more fun, or at least interesting, if you learn it properly rather than cramming.

When I get to revision I realise this, but by then it� . . . More

Researchers from Arizona State University have found the oldest solar system object ever discovered. In fact, it’s so old that it formed up to two million years before the solar system did, according to current estimates. It might be time for a rethink of when and how our little place in the Universe came into existence…



Coming up with a successful model for the formation of the solar system is not an easy task. Such a model must explain everything we know about the solar system today, from the fact that all the planets revolve the same way around the sun and in the same plane, to the composition of the planets themselves.

The most generally accepted model is the Solar Nebula Disk Model (SNDM), which is a modern variant of the Nebular Hypothesis originally put forward by Laplace and Swedenborg in the 16th Century. In the SNDM, stars form in huge rotating clouds of molecular hydrogen. Our own Sun started out its life as a proto-star in one of these clouds, and formed when a small part of the cloud underwent gravitational collapse. Most of the collapsing mass went into the formation of the proto-Sun, with the rest making the protoplanetary disk that surrounded it. Next came planetesimals, which are believed to be the starting point of planets. It is thoug . . . More

So, Biochem Belle has passed the roundup baton to me this week… I just hope I can manage to do as good a job as she's done the past two weeks!

We need you!

This week we've been asking for more input than ever here at LabSpaces.

Since the clock is ticking, Biochem Belle took charge and posted a poll for everyone to vote on the topic of our next theme day. Genomic Repairman posted a last call for entries to the Fantasy Football competition he's organising with a few folks from Scientopia as well as the LabSpaces crew, and he also had some science questions that needed answering.

Biochem Belle also has a question: How many female scientists can you name?

Anyone for some science?

Evie has a great post on the . . . More

You may have noticed I've been a bit quiet for the past week or so. Well, that was partly due to going home to Manchester for the weekend, and partly because I've finally started working on the literature review that's due in before I start my masters project in October. This will be the first bit of real research I've ever done, and will be a big change from the kind of follow-the-lab-script-and-do-an-experiment-you-already-know-the-answer-to lab work I've been used to in the previous years of my degree.

And it turns out that physics is actually pretty hard. So far I've only read a thesis and some review papers, but not a lot of it is going in. Before I started I was feeling quite confident about the whole thing given that I've read proper research papers before (I do it all the time for my blog!) and, well, I actually quite like writing. But I've found that with these papers I can read the same paragraphs over and over again without realising, and I've come to the conclusion that there can only be one of two reasons for this. Either the whole of particle physics is completely made up and as a result everything I've read is nonsense, handily explaining why I don’t understand it, or, I'm really not cut out for this . . . More

Tomorrow morning, I'll be heading away from the bright lights of London towards the not-so-bright lights of my home town in the North West of England. By complete chance, my trip away from the city coincides with a yearly event that requires a clear sky and as little light pollution as possible to be fully appreciated. Other than finding the right conditions, all you need to do to witness this event is look up.




The Perseid meteor shower was first observed two thousand years ago, and is visible every year from around the middle July to the end of August. At the peak of the shower, there should be 60 or so shooting stars every hour - meaning anyone looking to the sky can expect to see around one a minute, depending on location and a few other factors that can affect visibility. This year, the peak of the shower is tonight at around 0100 GMT.

The meteor shower originates from the comet Swift-Tuttle, which was discovered in 1862 and has a solid nucleus that's nearly 17 miles across. Unusually, the comet is locked into an orbital resonance with Jupiter, meaning that for every 11 times Jupiter completes an orbit of the Sun, Swift-Tuttle will go round only once. It was last seen in 1992, but we see its debris every year in the form of the Perseids. . . . More

You've probably noticed all the stories floating around recently about the Sun's increase in activity and auroras being visible in places that they usually aren't. It's all been pretty exciting. Especially if, like me, you've always wanted to see the northern lights and there was a (very small, but still non-zero) chance of the phenomenon being visible in your home town.

In light of this (no pun intended), I decided a blog post about the science behind auroras was in order...

What exactly is happening with the Sun at the moment?

The Sun goes through cycles, each lasting around 11 years. During this cycle, its magnetic field increases and then decreases again. The magnetic field of the Sun is the source of its "activity" - a term which describes solar phenomena like sunspots, faculae and prominences. Activity can also come in the form of coronal mass ejections (CMEs). These are huge bubbles of material with diameters a few times that of the Sun(!), that explode into . . . More

Neutrinos are elementary particles that travel close to the speed of light, but are very difficult to detect because they are not electrically charged. In fact, in the time it takes you to read this sentence, thousands of billions of neutrinos will have passed through your body - and you won't have felt a thing.

According to the Standard Model of particle physics, neutrinos should be massless - just like the photons that make up light - but in reality they do have a very small mass. What the Standard Model failed to take into account is the fact that neutrinos undergo something known as oscillations, or mixing.

Neutrinos come in three "flavours": electron neutrinos, mu neutrinos and tau neutrinos (as well as a corresponding antiparticle for each). When a neutrino is created, for example in the Sun during nuclear fusion, it has a specific flavour. Over time the neutrino can change flavour, but only if its mass is non-zero. All of the neutrinos created in the Sun are electron neutrinos. However, by the time they reach the Earth, we detect equal amounts of each flavour of neutrino; this is how we know that neutrinos must have mass.




Shaun Thomas and colleagues at UCL have now found an upper limit on that mass. It's the tightest constraint e . . . More

The LHCb is one of four experiments at the Large Hadron Collider (LHC) at CERN in Geneva. It will study the decays of particles known as B mesons in the hope of discovering the answer to a problem known as matter-antimatter asymmetry.

The problem is this: at the big bang, matter and antimatter should have been, and in all likelihood were, created in equal amounts. However, according to what we currently know, if they had been created in equal amounts, then I wouldn't be here to write this and you wouldn't be here to read it either. We exist due to a tiny imbalance in the ratio of matter to antimatter at the beginning of time. This tiny imbalance meant that when most of the stuff created in the big bang was annihilated (when matter meets antimatter both are destroyed and lots of energy is released) a tiny amount of matter was left over, and this tiny amount makes up all the matter we see in the Universe today, including us.





To investigate the matter-antimatter asymmetry, physicists are looking at B mesons. These particles are so called because they each contain a b, or bottom, quark. . . . More