While astronomers expend a lot of effort trying to see things better – building ever more powerful telescopes that can detect even the faintest, most distant objects – they are occasionally faced with the opposite problem: how to unsee things that they don’t want to see.

A group of scientists led by UCL’s Emma Chapman is working on methods to solve this problem for a new radiotelescope that is currently under development. In so doing, they could help give us our first pictures of a crucial early phase in cosmic history.

How to avoid seeing things you don’t want to see is a particular problem for cosmologists – the scientists who study the most distant parts of the Universe. Many of the objects and phenomena that interest them are faint, and lie hidden beyond billions of light years of gas, dust and galaxies. To make matters even more difficult, telescopes are flawed too – the data from them is not perfectly clean, which is manageable when you’re looking at relatively bright and clear objects – but a serious problem when you’re looking at the faint signature of something very far away.

Observing these phenomena is much like looking at a distant mountain range through a combination of a filthy window, a chain-link fence, some rain, clouds… and a scratched pair of glasses. In other words, you’re unlikely to see very much at all, unless you can somehow find a way to filter out all the things in the foreground.

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The Square Kilometre Array (SKA) is a new radiotelescope, soon to begin construction in South Africa and Australia. The SKA will use hundreds of thousands of interconnected radio telescopes spread across Africa and Australia to monitor the sky in unprecedented detail and survey it thousands of times faster than any current system.

One of its objectives is to make the first direct observations of a brief phase of a few hundred million years in cosmic history known as the ‘era of reionisation’. This technical term conceals something quite dramatic: a profound and relatively sudden transformation of the whole Universe, which led to the space between galaxies being fully transparent to light as it is today.

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Last week, asteroid 2004 BL86 passed near Earth. The ball of rock, a little over 300 metres across, passed 3.1 lunar distances from Earth.

This is far enough not to be of any serious concern – but it is closer than any other known asteroid will come to us until 2027. If an asteroid like 2004 BL86 were to hit Earth, we could expect widespread destruction – the famous Barringer Crater in Arizona was gouged out by an object just 50 metres across.

During its close approach, UCL’s observatory spotted the asteroid and snapped the picture above: a series of 30 second exposures separated by 9 second gaps. The asteroid can be seen moving rapidly against the background stars as the telescope was programmed to track the movement of the stars.

Reprogramming the telescope to hold the asteroid in its sights creates the image below – with the stars appearing as streaks instead.

This video, featuring a series of observations of the asteroid made at the observatory over the night of 26-27 January, shows both types of observation, including a long shot tracking the asteroid across the sky.

Images by Steve Fossey, Theo Schlichter and Ian Howarth.

Links

• University of London Observatory
• UCL Physics & Astronomy
• Article on radar imaging of 2004 BL86

High resolution image

• A high-resolution image can be downloaded from Flickr

The life of a spacecraft can be a difficult one. It’s made even more challenging with the amount of space debris that exists. The debris comes from a range of sources – mainly old satellites and rocket stages.

Using radar techniques the debris is monitored, with over 22,000 pieces that are bigger than 10 cm wide currently being tracked.

There are probably millions of bits smaller than this that can also cause damage.

Hinode was launched in 2006, and had previously made one spacecraft manoeuvre to avoid debris. This was back in March 2012.

This debris-avoidance manoeuvre (known as a DAM) involved changing the orbit of the spacecraft by using the thrusters. The instruments onboard were put into a safe mode and stopped operating during this time.

In January 2015, preparations were made for a possible DAM on 19 January, but as the time approached it was possible to cancel the DAM as the collision probability became low enough as the orbit prediction was revised.

On 26 January another piece of debris was deemed to have a high risk of collision and the DAM was set into motion. The instruments were put into safe mode and stopped operating over the weekend. The spacecraft did not have to carry out the manoeuvre in the end, and after the close encounter the spacecraft was safe and is in its usual orbit.

The instruments will start operating normally once again on 29 January.

Space debris is an ongoing and increasing problem, and no doubt more of these alerts will be coming in future.

• Louise Harra is Professor of Solar Physics at UCL, and is the UK scientific leader on the Hinode Extreme Ultraviolet Imaging Spectrograph, part of the Japanese/US/UK Hinode spacecraft

This image shows a scanning tunnelling microscope (STM) image of a molecule of iron phtalocyanine, separated from an underlying layer of copper by a thin barrier of copper nitride.

The image is part of a new piece of research just published by UCL scientists. The iron phtalocyanine molecule forms part of a tiny magnetic sensor which is sufficiently sensitive that it can detect molecule-sized magnetic fields. This technology could allow far smaller hard disks and new computer memory designs.

• Read about the research in full

Links

• London Centre for Nanotechnology

High resolution image

• A high-resolution image can be downloaded from Flickr

By 2050, London is likely to be severely in drought. The cause is a combination of growing population, the way we use water and pipe it around our cities and towns, and climate change. If we carry on as we are, there will be a deficit amounting to the water use of 2 million people in a short few decades. On the other hand, risks of water related natural disasters are set to increase, particularly the likelihood of large parts of the UK submerging if all Arctic ice melts. It’s the same story around the globe.

We know all this, and yet as a species we are doing little to address the problem. We protest, we raise awareness, but overall we are still heading for a vastly altered world.

This week, I’m exhibiting my sculpture Not Waving at The Crystal in East London, as part of New Atlantis, an immersive theatre production from LAStheatre. Consisting of 100 miniature people atop 3 miniature icebergs in a bath, an urn and a lot of clever electronics, this interactive installation determines the micro-people’s fate dependent on how much we are chattering about #water on Twitter. Tweet enough and they may survive the show, but if there isn’t enough chatter, water is released from the urn above them – they are drenched and doomed.

The icebergs are made of between 3 and 6 litres of water, which takes quite a while to freeze. Preparations for the sculpture began back in late November, when I started making the moulds for the icebergs with the help of prop-maker Ben Palmer. Once the moulds were ready, I brought them to UCL’s Ice Physics lab where the icebergs were frozen over the course of the last 2 months by Ben Lishman, of UCL’s Institute for Risk and Disaster Reduction, who’s also appearing in the show.

Next came the electronics – a Raspberry Pi and servo hacked into a water urn. This rig talks to the internet and controls the urn’s tap, releasing water when there has been insufficient tweeting about #water. What’s insufficient? Well, I worked out an average number of tweets per 10 minutes across an evening, and set it at just above that mark – 50 per 10 minutes. This is all connected up to a screen, programmed with the help of Jun Matsushita to look like this:

Of course, the secret is that the fate of our 100 micro-people is sealed: the urn will empty into the bath at the end of the show. Because it turns out social media chatter doesn’t change our fate – we need to act here in the physical, real world. The one in which the water is wet, the ice is melting, and the little people are struggling to stay dry.

That’s the reason the drowning is staged in a bath, with a hot-water urn above it, and tweets scrolling on a screen above that. All these activites – heating and processing water, and our endless online activity – they have a carbon footprint. They are all contributing to climate change.

Happily, we aren’t at the end of the show yet – and New Atlantis gives the audience the opportunity to learn about how we might deal with water stress in the future – and make decisions within the world of New Atlantis about how we might move forward.

Lots of the details of production are on my blog, and if you’re thinking of doing something similar I’d be very happy to tell you more of what I’ve learned. I also explain a bit more about it in this interview for iScience.

If you’d like to check it out, New Atlantis runs until the 25th January at The Crystal.

Kat Austen is Artist in Residence at UCL Faculty of Mathematical & Physical Sciences

Related links

• New Atlantis
• High resolution photos

Labs are rarely spotless. They are working spaces, busy with people. They are difficult to clean. They are also often home to some pretty messy scientific research. In fact, labs often look more like a workshop or garage than they do the gleaming white rooms we see on TV.

One glaring exception to this is the cleanroom at the London Centre for Nanotechnology. This lab is home to work that would be damaged even by tiny amounts of dust.

For instance, in the photolithography section (above), scientists use light to etch nanoscale circuits and patterns onto silicon surfaces, a process used to make electronic components. Even a speck of dust could derail this by casting a shadow on the surface and ruining the pattern.

For the same reason, the room is lit only with orange light. The light used to etch the surfaces is closer to the blue end of the visible spectrum, and any stray blue light could ruin the process. The distinctive lighting in the room avoids any inadvertent damage being caused to the experiment.

Links

• London Centre for Nanotechnology

High resolution image

• A high-resolution image can be downloaded from Flickr

Amidst the indescribable stress that is writing up my PhD, there is a massive silver lining. I’m currently writing this from 2,800m (that’s about 9,200 feet), half way up the Mauna Kea volcano in Hawaii. I say volcano, it’s not actually erupted for several thousand years and (the reason that I’m here) it has billions of pounds worth of massive telescopes on top of it.

During the second year of my PhD, my supervisors and I, whilst looking at some data everyone had assumed was assumed was empty, discovered the first molecule containing a noble gas in it in space. Those of you who know anything about Chemistry will know this is really weird. Noble gasses are so named because they’re noble: they don’t mix with the other elements.

However, in the remnants of a star that exploded around 1000 years ago, the conditions for it to actually do so happened. This is a massive deal and needs following up quickly – which as well as taking over a substantial chunk of my time over the past year has now brought me to Hawaii.

Last night was my first trip up to the summit, where I spend several hours at NASA’s Infrared Telescope Facility. It’s an odd experience being that high up. Everything needs to be a little bit slower. There are perpetual reminders that you are somewhere not normal. From the warning signs to the bottles of oxygen placed liberally around the control room.

People don’t function so well that high up.

Our trip was mostly to acclimatise to the 4,200m altitude and get used to the instruments we will be using. This is a good thing, because while Mauna Kea has 350 clear nights a year, last night was not one of them.

Last night there was a storm. The drive up to the summit was a pretty hairy experience with squalls of wind  and rain. Thankfully it wasn’t me doing the driving.

The only work that needed doing last night was calibration set up, for which we didn’t need to be able to actually see stars. Just as well, as there’s no way that we could have.

This weather system should have passed by tomorrow so we’ll be free to do science.

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Night 2

Tonight’s drive up was much clearer. As well as stars we could see the top of a thunder storm out over the pacific and the orange glow from a neighbouring volcano (a nice reminder that although it hasn’t erupted for several thousand years, Mauna Kea is not actually extinct).

Clearer… until we got to the summit.

Having prepared and calibrated everything and chosen our first standard star to use as a check for everything, the Telescope Operator said “no”.

Apparently it’s 100% humidity outside and it is lovely and misty.

We had a slight tease at about midnight: we got as far as opening the telescope dome and finding our standard star. Alas, just as we started taking actual measurements the humidity shot back up and we had to close the dome.

Night 3

There’s a massive difference when we get up to the summit tonight! Stars! I can see stars, not particularly brightly, which is mostly to do with the lack of oxygen at this altitude meaning my eyes aren’t working as well as they should, but stars!

If I can see stars, the telescope can see stars. After some changing of instruments and refilling of coolants (no mean feat at that altitude) we were finally ready to get started.  We found and observed out standard star without much of an issue.

Then we started looking for the little “knots” of gas we are observing in the Crab Nebula.  This took us a while longer than planned, but we got there and all lined up on the instrument so we could get the data we need. Nothing. Tried again. Nothing. By this time it was also about 3am, the combination of the time and the lack of oxygen made this all rather difficult to cope with.

We set the telescope to run for a two hour run to see if we could get anything at all.  Other than some cosmic rays (really not what we’re looking for at all) we got… nothing.  Frustration and worry about our calculations and whether what we were doing was right ensued.  I paced. Lots.  As the sun came up I went outside to get some fresh air (and see the telescopes, I’d only been up here in the dark until now), before heading down to the base camp for some fried food and sleep.

Night 4

I woke up this “morning” to an email telling me that there had been something wrong with the instrument. Good news as it means we’re probably going to get some good data this evening. Bad news because it was a really simple fix that had we known about it would have allowed us to get some good data last night too.

Ah well, onwards and upwards.  After another slog to get set up and find a new brighter standard star and things, we got observing.

Final night lucky, at about half past three, we finally realised we’d found what we were looking for! Massive amounts of relief all round, we still had to finish the run and get as much data as we could before the sun came up, but we got some.

It’ll take several weeks of processing the data followed by several more weeks of analysis before we know exactly what we have.

That can wait until after I’ve finished writing my thesis.

Patrick Owen is a PhD student in UCL Physics & Astronomy, and has recently returned from observing in Hawaii

Francis Galton was a pioneer of genetics and heredity (if you like him) or eugenics (if you don’t). He was also Charles Darwin’s cousin. Although Galton never worked at UCL, he was close to the institution, in particular as a close collaborator of Karl Pearson, the founder of UCL’s statistics department. Galton left his collections to the college on his death in 1911.

He was unquestionably brilliant, but also a problematic figure, particularly by today’s standards. In his partial defence, the term ‘eugenics’ – which he coined – was far less loaded in his time than it is today. The depravity of the Third Reich was yet to come, and the worst abuses of European colonialism were not widely known. Both, of course, were rooted in the ‘scientific’ racism of eugenics. Moreover, things which are quite uncontroversial today, such as contraception, were considered to be part of eugenics.

But for good reasons, he remains controversial.

Galton was a polymath, working across disciplinary boundaries and making contributions to many areas of knowledge. One of his more offbeat proposals is reproduced above: a letter to Nature, proposing a new and efficient way of cutting cakes, based on ‘scientific principles’. ‘Scientific principles’ in this case appear to mean avoiding the cut surfaces drying out, no matter how ridiculous the method turns out to be.

Here at the UCL Science blog, we think his work on cake is like his work on heredity: historically interesting, but contentious.

We would also like to propose a more efficient way of slicing a cake, which like Galton’s, avoids the surfaces drying out, but unlike Galton’s, requires no elastics and produces equally-sized and shaped slices: cut the cake horizontally.

Merry Christmas.

Tip of the hat to Prof Joe Cain.

 

 

 

Supercomputer simulations carried out by UCL chemists have successfully modelled the behaviour of clay-polymer nanocomposite materials. These materials, produced by dispersing tiny particles of clay through polymer (plastic) are widely used in industry.

Clay particles are made of tiny mineral sheets; plastics are made of long chain-like molecules. The way these interact when they are mixed determines the properties of the resulting composite material.

In the simulation, images of which are shown above, the polymer chains do not only surround the clay particles, they actually slide into the gaps between the sheets that make them up.

Read a full report of the science behind these pictures on the UCL Mathematical & Physical Sciences website, or read the coverage of the breakthrough on BBC News.

Links

• UCL Chemistry
• UCL Centre for Computational Science

High resolution image

• A high-resolution image can be downloaded from Flickr