Big data from new telescopes

I read an article recently on the Guardian's science website called Big universe, big data, astronomical opportunity. The article discussed the rise of large datasets in science, particularly in astronomy, and the need for astronomers to adapt to the challenges faced by this by acquiring new skills for analysing such data.

The Large Synoptic Survey Telescope
(Credit: LSST)

The article made many good points about the rise of big data. We are, after all, on the verge of a number of large projects that will produce more data than we've ever seen before. These include the Gaia satellite (which I've talked about before), new sub-mm and radio telescopes such as ALMA and the Square Kilometre Array, and the Large Synoptic Survey Telescope. The latter is particularly noteworthy because once it enters operation in 2022 it will produce 30TB of data each night, more than most telescopes produce in a year!

Astronomers will need to learn not just to manage these datasets, but to effectively sort through and process them. New algorithms will need to be designed, utilising artificial intelligence and advanced machine learning methodologies, as well as new approaches to visualise and understand the results. Astronomers will have to embrace this because this is the way science is going, and the telescopes that will produce this data are already being built, or in some cases are coming online as we speak.

Despite making these good points the article then appears to suggest that these new telescopes and satellites, designed to answer the most far-reaching questions humanity has ever asked, aren't what we need. "Have we leaned all that we can from the data that we have?", the author asks, suggesting that we should analyse all the data we have before collecting more. The article even suggests that the data we have could "hold answers to some of the fundamental questions of the Universe we are seeking".

I strongly disagree with the author on this point and find this attitude rather short-sighted. The data that we have may provide answers to some questions, but certainly not the big questions we want to answer, and that's where we should be investing our efforts. We won't find answers in our existing data to questions such as how the Sun and the Earth formed, how the Universe began, or whether there is life out there, it's just not possible.

Astronomical research is the continuous pursuit of answers to the greatest questions we can ask. We usually can't answer these questions in one go so instead we answer them step-by-step, performing experiment after experiment, refining the question as we go. For each experiment we design the equipment needed to answer the question, and then when that question has been answered we take the research further. If the same equipment or telescope can be used to answer the next question then we use it, but often the next question involves looking further, deeper and at different wavelengths, requiring new telescopes and equipment.

Just because a lot of data already exists doesn't mean that the answers to our questions can be found there. The great explorers of the past didn't discover new continents by searching around at home, they built great ships and went in search of discovery. Astronomers shouldn't be searching around in old data, but building great telescopes and searching the skies for their discoveries!

X-rays from stars

Tomorrow I'm going to a small conference at the University of Warwick to talk about X-ray emission from stars and our Sun. It may surprise many of you to learn that our Sun is a relatively bright source of X-rays, and it certainly surprised most astronomers when this was discovered in the 1940s!

Why is this such a surprise? Well, the surface temperature of the Sun is a relatively modest 6000 C, which may seem like a high temperature to you and I, but its certainly not hot enough to emit X-rays, which require temperatures of millions of degrees. And yet when astronomers launched the first rockets above our atmosphere in the 1940s they found that the Sun was a bright X-ray source!

X-ray image of our Sun taken from the Solar Dynamics Observatory
(Credit: NASA/SDO)

As it turns out these X-rays don't actually come from the surface of the Sun but from a region above the surface called the corona. You can see this in the X-ray image above, which shows the corona reaching above the surface of the Sun. The corona is a hot, low density plasma of gas, which reaches temperatures of millions of degrees, making it very bright in X-rays but almost completely invisible in the optical part of the spectrum.

So why is the corona so hot if the surface of the Sun is much cooler? Well this is actually an open question that many astronomers are still trying to answer, and its a question I've tried to answer by studying other stars. Our current best guess is that the corona is heated by the release of magnetic energy generated deep within the Sun in a type of dynamo. Unfortunately we can't see within the Sun to work out how and why this is happening, which is why this is still an unanswered question. Hopefully tomorrow's meeting will shed some light on this topic!

Tycho Brahe's gin

Last year I attended a conference in Copenhagen and while I was there I wanted to visit Tycho Brahe's observatory. For those who don't know, Tycho Brahe is considered to be one of the greatest astronomical observers in history, particularly in the pre-telescope era in which he lived, and he made many notable contributions to astronomy, including reporting on the 1572 supernova that now bears his name.

Hven gin, made on the island that was once home to
Tycho Brahe's observatory.

In 1576 he constructed an observatory called Uraniborg, which was apparently very impressive. It was built on the island of Hven in the Baltic Sea between Sweden and Denmark, and I was interested in visiting the observatory to see what remained. Unfortunately, as I found out,  the observatory doesn't exist any more, which is a great shame. Luckily for me though I was at least able to bring some part of Hven home with me when I found out that the island is now home to a gin distillery, and since my wife enjoys gin I was able to find a bottle in a Copenhagen liquor store and bring her a bottle home. I'm told it's very good, Tycho would have been proud!

Which parties will improve science in the UK at this year's general election?

While this year's general election in the UK may not be focussed on science and engineering, these are areas that are very important to the economy of our country. Despite this, science and research have suffered over the last decade, particularly under the last government. As a fraction of GDP the UK's research spending is currently the lowest amongst the G8 and the world's major economies, and in 2012 research spending dropped below 0.5% of GDP for the first time ever.

Science funding as a percentage of GDP (Credit: The Guardian)

The UK is clearly dropping behind these other economies in terms of research spending and productivity, which will seriously affect our future productivity and economy. Since this is an important issue it can be useful to know where the major parties stand on science education and funding, and what they plan to do about these issues if they were to get into power.

To answer this question I've trawled through the various parties' manifestos, as well as their letters to the Campaign for Science and Engineering, to try to find out what the different parties plan to do about science after the election. This meant a lot of sorting through vague statements of support for science and education to find actual plans and promises that might mean something over the next 5 years. Here's what I found.

The two main parties, the Conservatives and Labour, aren't really making any strong promises. The Conservatives are promising to continue the current science budget for another year, though since that is a fixed budget it would likely equate to a drop in actual spending power due to inflation. Labour are promising to ensure that all young people study Maths until age 18, which would probably benefit scientific literacy levels, but only as a by-product.

The leaders of the four major UK parties, but who is best to
improve science in the UK? (Credit: BBC) 

The Liberal Democrats go a little further, partly by promising to continue the ring-fencing of the science budget, but also by ensuring that by 2020 both research capital and revenue spending increase in line with inflation. This is an improvement over the Conservative's fixed science budget, though it doesn't go as far as other parties are promising to go, as we'll see later. The Liberal Democrats also have a more promising track record on these issues, by attempting to get more scientifically-literate MPs into parliament and also by introducing a 5p plastic bag charge into supermarkets.

The UK Independence Party are promising to abolish tuition fees, though only for students of STEM subjects who stay and work in the UK for 5 years following their graduation. Offsetting this strong move though UKIP are also promising to leave the European Union, which they claim will reduce the regulations which hamper science and technology (I can't speak for any of these regulations myself), but this will also lose UK science of up to 1 billion Euros of funding that we currently receive from the EU every year. Furthermore UKIP are promising to repeal the Climate Change act of 2008, which includes carbon budgets and targets for this half century, and this, I think, is a dangerous move given the way the world's climate is going at the moment.

The Green Party
(Credit: Wikipedia)

The Green party have, perhaps unsurprisingly, made some of the most impressive promises, including doubling public spending on research over the next ten years to reach 1% of GDP, the sort of levels already close to being reached by major research powerhouses across the world such as the USA and South Korea. In addition to this they want to end undergraduate tuition fees and reintroduce student grants, both initiatives that should encourage more people to go to University, study the sciences, and therefore improve the scientific literacy of our workforce.

And finally, while I myself can't vote for either the Scottish National Party (SNP) or Plaid Cymru, since I do not live in either Scotland or Wales, it is worth noting that both parties promise to establish free education for all, including abolishing University tuition fees.

To the majority of people in the UK, there's a stark choice between the commitments the major political parties have made to science. The two largest parties, Labour and the Conservatives, clearly think that science is important, but not important enough to make clear and ambitious promises for how to improve science and engineering in the UK. The Liberal Democrats are offering a little more, as do the SNP and Plaid Cymru (if you are able to vote for them), but none of the parties go as far as the Green Party in making commitments to science for the next parliament.

Hopefully this has been useful for deciding who to vote for in the next election. Whoever you vote for, and whoever gets into power, I hope that science and engineering do well under the next government, for the benefit of our own country and everyone in it.

Happy 25th Birthday Hubble Space Telescope!

On this day 25 years ago the Space Shuttle Discovery was launched from the Kennedy Space Centre on Cape Canaveral in Florida. After launch the Space Shuttle rose to an altitude of 380 miles and began to orbit the Earth. In the days that followed the crew of the Space Shuttle opened the shuttle's cargo bay doors and deployed its valuable payload, the Hubble Space Telescope.

The launch of Space Shuttle Discovery, with the
Hubble Space Telescope on board (Credit: Wikipedia)

That was 25 years ago, and ever since then the Hubble Space Telescope has acted as the world's premier astronomical observatory. In that time Hubble has made an immeasurable contribution to our understanding of the cosmos, from measuring the speed of the expansion of the Universe, finding the first evidence for dark energy, and discovering planetary systems forming in the Orion Nebula.

The Hubble Space Telescope is not the only astronomical observatory in space, in fact there are dozens of them. It wasn't the first such observatory and it certainly won't be the last, but it is probably the most important, not just for the scientific discoveries it has made, but also for how it has brought those discoveries, as well as thousands of beautiful images of the cosmos, to the public. In this article I want to share some of those images, and the science behind them, with you all.

The Pillars of Creation in the Eagle Nebula, imaged by the
Hubble Space Telescope in 1995
(Credit: Hubble Space Telescope)

Perhaps one of the most famous images taken by the Hubble Space Telescope, and one of the first to lodge itself firmly in so many people's hearts, is the magnificent image of forming stars in the Eagle Nebula. The image, which was quickly dubbed the Pillars of Creation because of the stars being created within the nebula, showed for the first time the amazing detail in star forming regions such as this. The pillars themselves, sometimes referred to as elephant trunks, are giant clouds of gas and dust that are being slowly eroded by a cluster of massive stars just above this image. Those stars are sculpting and eroding this cloud of gas and dust, and potentially, as was later shown, halting the star formation process within them. The Hubble Space Telescope revisited this image as part of the 25th Anniversary celebrations this year, producing a new, larger and higher-resolution image of this amazing nebula.

The merging Antennae Galaxies, imaged by the
Hubble Space Telescope in 2006
(Credit: Hubble Space Telescope)

The Hubble Space Telescope didn't just spend its time imaging star forming regions like this, it also produced a huge number of very detailed images of distant galaxies. One of my favourite images of these galaxies is that of the Antennae Galaxies that has been imaged by Hubble multiple times, most recently in 2006. The Antennae are actually two galaxies that are in the process of merging as they interact, and this interaction has quite radically torn these galaxies apart, as the image shows. This apparent destruction has, rather paradoxically, led to a very brief but intense period of star formation that astronomers refer to as a starburst. The Hubble Space Telescope images are so detailed that they have allowed astronomers to study the star formation in these distant galaxies and even resolve individual star clusters within them. Getting such a detailed view of this important phase of galaxy evolution has been really useful for astronomers to understand how galaxies merge.

The Hubble Deep Field, imaged by the
Hubble Space Telescope in 1995
(Credit: Hubble Space Telescope)

Perhaps one of the most unique images taken by the Hubble Space Telescope is that of the Hubble Deep Field, which was imaged in 1995 from 6 days of exposure of an apparently empty patch of sky. This tiny area, one 24-millionth of the entire sky, was chosen because it was almost completely devoid of any stars and galaxies. The questions astronomers were effectively asking by taking this image was, what will we find in the darkest and emptiest areas of space?

The answer was that this apparently empty area of space was actually full of galaxies! Almost all of the 3000 objects in this image are distant galaxies, billions of miles away. Some of the galaxies are so distant that it has taken almost the entire age of the Universe for their light to reach us, allowing us to see what they looked like when the Universe was very young. Images like this have been vital for helping astronomers understand both the large-scale structure of our Universe as well as how galaxies have changed over the lifetime of the Universe.

Finally I want to end with a new image taken by the Hubble Space Telescope very recently. This image was released to the public yesterday to celebrate the 25th Anniversary of the launch of the Hubble Space Telescope, and you can see this amazing image below.

The Hubble Space Telescope's 25th Anniversary special image release showing the massive star cluster
Westerlund 2 and surrounding nebulosity (Credit: Hubble Space Telescope)

The image shows the massive star cluster Westerlund 2, one of the most massive clusters of young stars in our Galaxy (and one which I have studied in the past and talked about before on this blog). This image is so large and detailed that not only can you make out many hundreds of young and massive stars in this cluster, but you can also see the beautiful nebula that surrounds the cluster and make out young stars forming within it! This is an amazingly detailed image, which I encourage you all to have a look at in more detail here.

You can see more images like these on the Hubble Space Telescope's gallery webpage, or follow the various events celebrating this anniversary on the Hubble Space Telescope's 25 Years webpage. Over the next few months I'll talk more about some of the amazing discoveries from the Hubble Space Telescope, the history of how this great observatory came to be, and the exciting telescope being built to replace Hubble in the next few years.