Monday, 24 October 2011

Space's Explosive Candles

This blog post is an adaptation from this Object of the Day, which is an adaptation from my course at Queen Mary. Here will go back a lot further into the history of the violent events in space that prove vital to astronomy: the standard candle.

A hundred or so years ago, a computer went every weekday to Harvard College Observatory's plate stacks, and compared plate after plate of glass. That computer was a determinedly selfless lady named Henrietta Leavitt; "computer" was the job title of one who analysed astronomers' results, from plates to notebooks to calculations. "Plates" in this case were sheets of glass onto which projections from telescopes had been collected by a light-sensitive silver nitrate solution, capturing the patterns of stars. This meant both greater accuracy in measurements, and a permanent record. (Today, Harvard College Observatory holds thousands, although obviously they are no longer used for observing.)

A "positive" and "negative" plate could be taken of any sky area - white stars or black stars - and laid upon each other. These average out - if the two plates are exactly the same. But if anything has changed in that area of the sky, the object in question will leap out, starkly black or white against the grey.

In fact, this is pretty much the same technique as Ice Hunters uses; more on that in this post from June.

Women were not at that time permitted to use the telescopes themselves. However, as she worked - at first, without pay - on the thousands of plates, Leavitt spotted many variable stars. (Variable stars are stars that change in brightness; they had been objects of interest for some time, but regarded with as something amateurs rather than professionals studied.) The discovery she made that earned her a nomination for the Nobel Prize - but only three years after she died, by someone who was not aware that she was dead - was Cepheid variable stars, a type of star whose brightness rises and falls in direct correlation with its mass.

Stellar mass is directly proportional to its luminosity, and as light's intensity falls in direct proportion to its distance - the inverse square law - it is possible to tell how far away a star is. There are three factors, and if you know two, you can deduce the third. There's a brilliant explanation here at Hyperphysics about how the inverse square law of light (and gravity) works:

Leavitt did not know exactly how far away each Cepheid was, but she had a very useful sample to study: those in the Magellanic Clouds.

The Magellanic Clouds, so named for a Portuguese explorer, Ferdinand Magellan, who used them to navigate while sailing around Africa, are a couple of nice little dwarf irregular galaxies in the southern hemisphere. Leavitt did not know the distance to these, but did realise that they were far enough away that she could treat all the Cepheids in them as being effectively the same distance away.

This APOD shows the Magellanic Clouds over the Very Large Array during a lunar eclipse. The link will show you a map of what everything is in the sky.

Extrapolating her results led to a bombshell. As telescopes improved, Edwin Hubble was able to spot Cepheids in the Andromeda galaxy, and calculate their distance. Andromeda was completely separate from the Milky Way. Harlow Shapley, who while showing that Earth was not at the centre of the Galaxy was nonetheless convinced that our Galaxy was the only one, was shattered when he heard. He thrust Hubble's letter to him at his young colleague Cecilia Payne, saying, "Here is the letter that has destroyed my universe."

It turned out that there are several subclasses of Cepheid variables - and not knowing this led Hubble to wildly overestimate how fast the galaxies are receding from each other. Nineteenth century geologists, biologists and physicists had rocked the world by showing, through geology and evolution, and radioactive decay, that the Earth was over four billion years old rather than a few thousand as religious history taught; and Hubble's figures suggested that the Universe was only two billion years old!

Henrietta Leavitt had started a new way of looking at the Universe: she revealed the first set of standard candles. It was Walter Baade and Fritz Zwicky who discovered the next sort: supernovae.

Zwicky and Baade were close colleagues in the 1930s, but at the advent of the Second World War, some scientific friendships fell apart (the most famous being that of Heisenberg and Bohr) and theirs was one of them. But they both made outstanding contributions. Zwicky predicted gravitational lensing and dark matter, and Baade identified Population I and Population II stars, which taught us a lot about galaxies. But they had time to separate the already known novae from the much more impressive supernovae, and to predict the neutron star - the complete collapse of an object that had reached the Chandrasekhar Limit.

Chandrasekhar, known as Chandra, had predicted a strange but inevitable law of white dwarfs. A white dwarf is what is left of a star once it has burned all the hydrogen fuel in its core (the hydrogen at the edges is too far away and too cold), and it has stopped shining - though it will remain extremely hot for billions of years. However, should this white dwarf have a mass more than 1.4 solar masses (a solar mass is the mass of the Sun - about 2,000,000,000,000,000,000,000,000,000,000 kg, if you care) its gravity will be stronger than that of the repulsion between electrons which basically gives everything its solidity. This idea was not widely accepted, and he could not predict what would happen. Baade and Zwicky, with more observations and probably more knowledge of nuclear physics under their belts, predicted that protons and electrons would fuse into neutrons. This gives off a staggering quantity of energy, and because electron orbits make up virtually all the volume of an atom, the white dwarf shrinks to a tiny, unimaginably dense object only about 20km across.

A neutron star is what is left after a supernova. (Supernova 1987A, on whose rings the Galaxy Zoo logo is based, has confused astronomers by not so far appearing to have left one.) As with Cepheids, there are different types of supernovae. The most important difference is type I and type II. Both basically involve the collapse of the star's core. (Stars don't automatically collapse when their cores are over the Chandrasekhar limit because of the furious heat of nuclear fusion maintaining an outward pressure.) Type II is the explosion of a star between nine and and up to fifty times heavier than the Sun.

A type II supernova still has an outer layer. A type I supernova does not. These are divided into the subclasses of type Ia, Ib and Ic. Type Ia is the collapse of a white dwarf that has accumulated more material since the star's outer layers were puffed off into space. Types Ib and c are the core collapse of a star, making them more similar to a type II explosion, but their outer layers do not contain hydrogen. Type Ia supernovae have a very special property: the transition from white dwarf to neutron star always happens at precisely the same mass - 1.4 Suns, the Chandrasekhar limit.

And because they are of the same mass, the explosions are of exactly the same brightness. Therefore, they are an ideal standard candle. And because they can outshine entire galaxies, these candles can be seen billions of light years away.

It was examining those that are fairly far away that led to the Nobel prize winning discovery of the accelerating expansion of the Universe. By "far away" I mean with a redshift of under 1, so not exactly at the edge of the observable Universe: far enough to get a really large scale of what is going on, but not so very far that we're looking back at ancient history. Near enough to give a picture of modern times. Naturally that discovery is still being questioned, but the papers (Perlmutter et al and Riess et al) were extremely thorough - indeed, thorough enough to be held up as examples worth learning from, as well as critiquing, as part of my course!

What they found was that the supernovae were fainter than we would expect. And because this is, basically, a local effect - though one over huge scales - it means that expansion is going faster than we thought it is. We know that inflation, unfathomably rapid expansion, took place when the Universe was less than a second old. But we had been assuming the Universe's expansion was slowing down ever since - like a ball thrown up into the air, ready to hover for a moment, and then crash through the greenhouse windows or into a paddling pool or similar.

It turns out the ball has a booster rocket, which is dark energy. The density of dark energy never changes - but, as the volume of of the Universe is ever increasing, the density of matter decreases all the time. There isn't much dark energy about per given volume. But there's more all the time. And we found all this out through standard candles.

Just how standard is a standard candle? Science is never as straightforward as would be convenient - though that only contrives to make it even more interesting!

Not all Type Ia supernovae are made quite the same way - or, to put it in more scientific terms, they may have different progenitors. A white dwarf may start off as under 1.4 solar masses, but accumulate enough material to pass that limit. There are two ways it can do this, and both ways are through starting off as a binary star system. Its companion may still be a star, and it may drag off its outer layers. Or its companion may also be a white dwarf, and they might merge.

(It used to be predicted every so often in astronomy that a star might grow by passing through a nebula, but in practice nebulae are far too rarefied for this to be more than negligible - and the star's stellar wind drives off surrounding gas anyway. Also, two white dwarves merging will not make a type Ia supernova if the both their masses add up to less than the Chandrasekhar limit. If that happens, if they have enough hydrogen, they will become a star again!)

This little theoretical paper predicts that the "single degenerate" supernova - the star plus whit dwarf - will explode in the direction of the host star, and contain hydrogen from the star in its spectrum; while the "double degenerate" supernova - the two white dwarves - will have a different shape and contain no hydrogen. (They are called "degenerate" because the term "electron degeneracy" refers to "degenerate matter", i.e. matter crushed to a point where it only stops being a neutron star because of the electrons holding it apart.) It predicts, in the latter scenario, that the lighter white dwarf will break up and form a ring around the heavier - like Saturn's rings - and the resulting explosion, when it occurs, "may be expected to be axially symmetric, but predominantly of the form m = 2. That is, there is an additional reflective symmetry about the equator. Here the character of the explosion changes monotonically as the viewing angle moves from the pole to the equator." (I think I know roughly what that means, but I'm not quite sure how to describe it! Also, we do not yet know whether or not that paper's predictions are correct. Science will, hopefully, find out.)

It also depends on what the white dwarf is made of, as pointed out by Robert Gagliano, who is one of the major posters on Supernova Zoo. Even if the explosions have roughly the same characteristics, their spectra will not, for white dwarfs may be made of carbon, sometimes oxygen, and may or may not also contain hydrogen and helium, which may or may not be ionised - all these affect the spectrum.

Finally, and to me the most interesting point of all: as this paper points out, although there aren't necessarily two distinct types of Type Ia supernovae - there is more a continuum (like galaxy shape, really) - it is established that spiral galaxies tend to host brighter supernovae than elliptical galaxies. This paper, from zookeeperKevin, points out that it is correlated with a galaxy's starforming rate. One of Galaxy Zoo's great finds was about galaxies and colour. "Roses are red, spirals are blue, or at least so we thought until Galaxy Zoo": spirals tend to live alone, where there is plenty of free cold gas, and therefore are blue with star formation. Ellipticals tend to live in clusters, where there is no free cold gas, and are therefore "red and dead". I've written more about this here. The exciting exceptions are blue ellipticals and red spirals. What, I would like to know, are their supernovae like?

A normal red elliptical, normal blue spiral, less normal blue elliptical, and less normal red spiral, taken from the Galaxy Zoo Forum.

Now, if all that fried your brain, go and soak it in the music of a Supernova Sonata, or read Alice Allen adapting William Blake to the supernova.

Friday, 14 October 2011

Cults, laws, and free speech

Cardiff Skeptics in the Pub turned a year old on 20th September. The day before - it also being a Monday - we held its birthday party, with crisps, cakes, balloons and two very special guests: David Allen Green and John Dixon to revisit #Stupidscientology.

Thank you @wmjohn for this photo. Are there any more?

It was a good time to be all insane and swoony over the astonishing fact that our baby group had launched a whole year ago - that had been a pretty good day too. Thanks to all the speakers who've been so far: Simon Perry, Ash Pryce, Andrew Holding, Simon Singh, Hayley Stevens, Deborah Hyde, Jon Ronson, Trystan Swale, James Onen, obviously David and John, Rhys Morgan who's every so often had another news snippet for us, and the great comedy cast of July, whose names for which my memory is embarrassingly incomplete. And the people who've helped with lifts and chair stacking and spreading the word, generally being enthusiastic and supportive, and the audience for keeping us going, and the lady who brought along some profiteroles!

Appreciation expressed, to I hope the smiles of those receiving it and not too much boredom from everyone else (Skeptics leaders love it when you visited one of their events!) - we visited the subject that had got John famous. It may look like an idiotic piece of red tape, political correctness gone mad etc on the surface, but the implications were surprisingly sinister.

David has written a brilliantly detailed blog post about it here; I recommend a read. In short, John, in between tweets about what he was up to in London, had tweeted that he was hurrying past a Church of Scientology so the stupid didn't rub off. A while later, a scientology Twitter account began following him. Well over six months after this, someone complained to the council about the tweet, mentioning, I might add, that they thought there might have been two other tweets they objected to but they could now no longer find them on Google. It was a great many months more before his fellow councillors could make the decision what to do. In the end, they did not take it to court, though John gave us the impression that he might rather have enjoyed himself if they had.

John defended himself with great humour and sense: someone having attempted to make him look a bigot, he was able to raise awareness of quite a lot of unsavoury information (links provided by me, not him) about the Church of Scientology that made "stupid" look like the kindest possible description. You might enjoy this video of him standing up to Kirsty Wark, and being much politer than she was in her attempt to make him appear rude. David's knowledge of law gave him expertise in tackling this issue of free speech defense versus "bigotry" accusation, with weapons I would never have thought of - for example, in his criticism of the document by the Ombudsman, he did not mention the author, because "you can't defame a document". John actually skyrocketed to fame whilst in a tedious two-hour meeting. His mobile was switched off, and he had no knowledge that David had brought the case to the country's awareness. When he switched it on, he had 700-odd new followers and umpteen tweets and voicemails waiting for him.

This is of course far from the first time David has got involved with an issue like this. Not scientology, but a case where the law is being treated as a weapon, rather than a means to get justice.

"The Church of Scientology has as much right as anyone else to assert and protect their ultimate legal rights," he writes. "But it is misconceived and illiberal for litigation (or the threat of litigation) to be used by itself as a weapon."

L. Ron Hubbard, who founded Scientology, is quoted as saying:
"The purpose of the [law] suit is to harass and discourage rather than win. The law can be used very easily to harass, and enough harassment on somebody who is simply on the thin edge anyway, well knowing that he is not authorized, will generally be sufficient to cause professional decease. If possible, of course, ruin him utterly."
In other words, the point is not winning or losing. As Simon Singh found out, even if you win, you have lost thousands, sometimes tens or hundreds of thousands, and years of your life. Very few people in their right mind would take that on if there was any way out. The way out is to back down, to apologise, to retract all your statements, to make out that the individual or organisation suing you has nothing to be ashamed of - and your peers will self-censor their own work, too.

I had something like this happen to me 11 years ago, albeit on a much smaller scale. A boss in whose employment I had been extremely unhappy (the guy I describe at the end of this post, if you're interested) took it upon himself to tell the company treasurer I had said I didn't want to be paid for my last two weeks of employment at his firm - at least, that is what she told me when I telephoned to enquire. When I wrote to the firm to challenge this, I was fobbed off for 3 months (the 3 months in which an employee must begin an industrial tribunal), then suddenly accused of theft on the grounds that I had sent an e-mail to a friend with verbal permission. I was informed that there were 4 logged occasions on which I had been forbidden to use the Internet, and that two other employees had wasted four man-hours searching for any viruses I might have allowed into the company's computers, time I was being charged for.

The charges were blatantly ridiculous, since other employees had routinely used e-mails and often sent them to me, one of my duties was using the Internet, the boss was famous for never logging anything or even being able to use a computer, and he had even claimed that each man-hour cost the company £65 after I had spent the best part of a year daily logging man-hours which were £45. And, as Acas told him, it is illegal to deduct pay from an employee under such circumstances; you have to bring a case against them first. If anyone tried this nonsense on me now, I would laugh in their face. But I was only eighteen, I was extremely poorly, I was inexperienced, and I had spent months being bullied and humiliated by him and had had about as much as I could stand. Now obliged to fight for myself when I was least able to do so, I went to the Citizens Advice Bureau (now being cut all over the place), and although I did not win any compensation I was given back most - not all - of the money I was owed. But it took five months, by which time my sickness had become long-term. He never did drop his threat of suing me. My sickness and the worry that he might do it went on to ruin university for me and whenever I start any new employment I still have an undercurrent of alarm that something like this might happen again. Frankly, if I could have foregone my lost wages and allowed the wrong thing to happen, in exchange for having my health and confidence back, I know which I'd have chosen.

(I would love to name the individual and company that did this - and I bet I'm not their only victim - but sadly, I do not dare do so . . .)

The mere threat of litigation is a massive weapon. For me it was merely "civil action", minor but bad enough. For someone like Simon Singh, or Hardeep Singh, or anyone who someone with as much money as Hubbard had to use the law as a weapon as much as he pleased, the consequences could be much, much worse.

The law, there in principle to do a good and essential thing, can also ruin the innocent. That's why I admire David. He dedicates huge amounts of time and energy, often free, to fighting against that, and defending those to whom it happens.

But that's not the only way the law can be used for personal benefit rather than as it is intended.

A few days ago, Steve Jobs lost his battle with cancer. I've never been able to afford any kind of Apple product, but the effect they've had has really changed things - there's an app for Galaxy Zoo, for instance. The Curious Astronomer and the mother of a special needs child whose life was transformed by Apple have written about that. Sadly, certain people affiliated with Westboro Baptist Church were not so graceful.

This piece of utterly hateful loser-ness circulated the Internet quite a lot shortly after Steve Jobs's death. (She then claimed that God created the iPhone purely so she could insult its founder . . .)

Even though I didn't know much about Steve Jobs, and I'm certainly not an uncritical fan of Apple, I exploded with indignation when I read this. Death hurts. How can anyone use the occasion of someone's death to pick on their relatives? As I've just described, to be kicked when down makes you feel desperate. Why do Jobs's relatives deserve to be made to feel desperate when they're saying goodbye, already knowing the world is watching them?

How, I tweeted, was this kind of harrassment even legal?

I was then immediately challenged by someone I hadn't come across before: Donalbaion, a mature student in Physics. He pointed out that I was arguing against free speech. Simple as that. To deny Westboro Baptist Church the right to harrass the grieving was anti-free speech.

Initially, of course, I was even angrier. Honestly, who would be suffering from a deprivation of their rights more: the bullies, who would be told "No you can't upset these people", or, say, someone who might have to hold a funeral in secret (and therefore deny many others the chance to mourn) if they didn't want to be psychologically attacked? What kind of freedom is it when you can't even have a funeral in peace?

But of course, anger alone isn't much of an argument. What would be the consequence if Westboro Baptist Church was not allowed to exercise its freedom of speech by picking on grieving people?

Donalbaion tweeted me this review of the book "When the Nazis Came to Skokie". In summary: in 1977, Skokie was an area in which a sixth of the residents were Holocaust survivors and their near families. In this very area, a neo-Nazi group wished to demonstrate. The residents fought against this, citing not only the worry that violence might erupt from the demonstration, but their right to live without intimidation from a group who presumably supported the horrors they'd gone through. But on the other hand, to refuse the neo-Nazis a right to protest would violate freedom of speech. The review concludes: "Strum's book shows that freedom of speech must be defended even when the beneficiaries of that defense are far from admirable individuals."

In other words, once someone (say) took out an injunction against Westboro Baptist Church, who else might lose free speech as a consequence? It could be anyone, for any reason. It's just too dangerous.

But that's not the end of the story. All that agonising over human rights, knowing that people are going to be bullied and degraded - that is, according to this piece of writing, precisely what they want us to do. Go and read it now.

Apparently, this is not about beliefs at all. Whether or not they honestly think God agrees with all their statements about who is going to Hell, their aim is that someone else will get angry enough to try and violate their rights somehow. And then they can sue them.

As "El_Camino_SS" has written:
I saw that he was way too calm and collected for what he looked like in the media. I noticed that he never made personal statements against a person, which is verbal assault, and an out against a lawsuit. Also, for a religious fanatic, a group of people who pride themselves on personal attacks, he was running a protest so terribly by the books that I was impressed by it. He will not bait a person, ever. He will not make personal attacks. He will make blanket statements. He will look at a person in the crowd that he thinks is gay, walk over to his stack of signs, pull out the appropriate, well designed, easily read, laminated bright board, and hold it up and loudly proclaim that "gays are going to hell" or some such nonsense, and make eye contact, but he will never cross the line of telling that person that they're going to hell. That would be the part that would screw up the lawsuit. He just wants to get them after him, but wants to appear utterly blameless for damages.

. . . They run too tight of a ship to slip up, and at that point, I realized that the objective of the group was not anything religious at all.
Assuming the above is true - and here I do not claim to know for sure - this seems to me another misuse of law, and it's even more cynical than the type of misuse about which Skeptics here in the UK have heard so much. It's not even, strictly speaking, misusing the law. It's not using archaic silly laws that are set up to benefit the already rich and powerful. It's using a hallmark of civilisation simply to try and get money out of people.

And frankly, I'm not sure if there's anything we can do. With the first type, we can sign the petition to change the UK's outdated and embarrassing libel laws. With this type? We can't change that law, because that way almost everybody would lose their rights, rather than in the above case, where so many would gain them. After all, a civilised society does not remove its welfare state because a handful of people abuse it. And Donalbaion was right to point out that we cannot put free speech to a majority at risk because a handful of people abuse that.

I suppose, in this case, that if anything can be done, it could be a grassroots, done-by-the-people effect. For example, stronger people are less bothered by banners which display the words "God" and "Hate" in the same breath - so a campaign to give people strength in some way. Perhaps similar banners could be waved, saying something like "Civilised people don't target the grieving" - using the Phelps' tactics of blanket statements and never coming across as personal. Just showing solidarity. Bringing a society to a point where it no longer cares. Of course, you good folks in the States may already be doing that; I honestly don't know. My post is about law and free speech, not about any particular church.

And there are things that to some extent make up for the worst. For instance, according to that journalist's post, at least the grieving cannot be verbally attacked, and that these folks only stay for a maximum of 30 minutes. And, more importantly, they are a tiny minority. Take a peep at this Apple store in Chicago (photo taken by Arfon from the Zooniverse). We may not all be Steve Jobs, but if your rights have been violated, in most cases in civilised countries it will only be a few people who've done it, rather than an entire society. Often, most people are on your side.

Saturday, 8 October 2011

Astrophysics, here I come

Whew! I'm here!

"Here" is London, the city I was born in and still think of as home. Through a friend of a friend I've found some lovely lodgings just outside the North Circular and am getting used to cooking for one again. All of a sudden there are things going on all around me. There are kids playing with remote controlled cars in the streets, there are buses and trains for which I seldom have to wait more than one or two minutes, there are endless food shops, there is shouting and laughter, there are beautiful parks, there are such a huge variety of people, there are all these friends I can meet without travelling for hours. And there is Queen Mary University and a course which, so far, looks as if it's going to be the course of my dreams.

Over the years of running the Galaxy Zoo forum and getting more and more interested in astronomy, I became increasingly aware of the gaps in my knowledge - the more I knew, the more I found there was to know for which knew I needed some training. Absorbing facts is one thing, but mathematics and computer code and the language I call "journalese" (in other words, the very dry style in which scientific papers are written) is quite another. My knowledge contained some of the gorgeous constructions of science, but without the nuts and bolts to hold them together or build on them. The trouble was that neither my undergraduate degree in Environmental Sciences nor my attempt at teaching had been any encouragement to study any more. I had long stopped thinking of myself as academically minded. So I had thrust the idea into the back of my mind and it stayed there for years, until one tedious morning driving to a pretty useless course I was on for work when the idea of doing a masters in astrophysics suddenly popped into my head like a massive bright gold light being switched on.

At work later that day I snuck onto Google and by that evening I knew which course I wanted to do: this one. There weren't very many others, to be honest (at least not without also doing an undergraduate degree), but this seemed both the friendliest and the best tailoured to what I wanted. I began filling out the form, but procrastinated, worried about money and unable to get hold of one of the referees I had in mind. Then it was off to Boston for the 218th AAS Conference and that was it.

That conference was one of the happiest times of my life. I was invited into what turned out to be a waterfall of astrophysics, flooding me from all sides. Everywhere I went there was more. And miraculously, I found I actually understood a lot of it. Not a large percentage. But I did begin to notice that what I wasn't understanding was the jargon, the mathematics, the acronyms. The concepts themselves were fine. And many astronomers didn't understand the acronyms either: astronomers were specialists, so a cosmologist for example might be bemused by the many Kepler reports on extrasolar planets - and they were quite happy to tell me so. Even more encouragingly, several astronomers wanted to talk to me at their work, and were quite happy to explain things to me in detail. Since I was writing an article for the Astronomy Now magazine, and because the older I get the less self-conscious I become, I never worried about putting my hand up in seminars or press conferences to ask questions. And the upshot of that was that I heard the same thing from umpteen genuine scientists: "Where do you study?" and upon hearing that I was not a student, "Oh, you must do a PhD! Your questions are really good - you've obviously got a great aptitude for this subject!"

(It's really hard work, not aptitude, but we are often reminded that the former is what really makes the difference. For instance, I also used to be one of the worst public speakers I know. I just curled up and mumbled. Seriously. Now, due to repeatedly bludgeoning myself with the task, public speaking is one of the things I'm best at. In fact this was one way I reasoned myself into going ahead and applying: if you can run the Galaxy Zoo Forum, co-found Cardiff Skeptics and learn public speaking, I told myself, you can conquer mathematics. We'll see in the next few weeks if I was right . . .)

This autumn, I'm studying Cosmology and Research Methods. The latter is quite a new course and there is some worry that it seems "soft" and is somewhat hard to teach. It's actually incredibly valuable - everything anyone studying science needs, everything I wish I'd been told as an undergraduate, everything you need to know if you want to back up some claim you've made (or debunk someone else's). The material we are reading for it is also anything but "soft"! Next term will be Astrophysical Plasmas, and Extrasolar Planets and Astrophysical Disks, both of which sound pretty mysterious! Next year will be the Galaxy, the Solar System, Stellar Structure and Evolution, and Electromagnetic Radiation in Astrophysics - these are all more familiar to me and I can't wait to take them, but since it will also be my dissertation that year, I'm glad to be getting the difficult things out of the way now.

It's a part-time course because for one thing I want to go slowly and for another and MSc course is expensive, as is living in London. So I'm also looking for a job. If you happen to know of any science or science communication related jobs, please let me know. Science communication would of course be my ideal, but I realise I can't be choosy! As well as astronomy I have some background in Environmental Science and Chemistry, plus teaching English and Science, plus other supervisory roles, plus an awful lot of admin. Oh, and some experience of working with vulnerable people - which has been the subject of a lot of my outraged-at-injustice posts the last year or so. Oh, and I'm a very good proofreader and editor. (This is not a post in which I'm going to bother to be modest.)

I'm hoping to get myself together and get blogging more; it's been a topsy-turvy year and I haven't done much for some time. Meanwhile, because I owe so much to Galaxy Zoo for getting me into astrophysics, and because it's so much more fun to feel as if I'm doing the course for hundreds of other people as well as me, and because it'll make sure I myself keep up to date, I'm writing about what I'm learning here on the Galaxy Zoo Forum. Please come along to ask questions and join the lively discussions it's prompting!

Apologies, also, for not writing an Ada Lovelace Day post. Today is Ada Lovelace Day, in which we celebrate women in science, and women who have influenced us. Can I make the excuse that I've been busy starting off on what might one day make me, myself, a female scientist? (I don't know if I will aim to do that or not yet. Let's just say that it looks a lot more possible than it used to.) Carolyn Porco recently tweeted a list of inventions you probably didn't know were made by women, and I also want to make a tribute to Wangari Maathai, a Nobel Peace Prize winner who died a few days ago. Her loss to the world is great: she has done amazing things for women, for politics and for the environment; you can read more about her at the Green Belt Movement.

Happy Ada Lovelace Day, and may neither men nor women ever be put off from learning!