Daniel Powell

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Warming gases reach record high

Warming gases reach record high http://www.bbc.co.uk/news/science-environment-24833148

Permanent link to this article: https://animatedscience.co.uk/2013/warming-gases-reach-record-high

Liquid metal inter-atomic distance shown to contract on heating, surprisingly | National Academy of Sciences


Permanent link to this article: https://animatedscience.co.uk/2013/liquid-metal-inter-atomic-distance-shown-to-contract-on-heating-surprisingly-national-academy-of-sciences

Chris Hadfield: ‘I’m blind, in space, holding a drill. Houston, I have a problem’

Chris Hadfield: ‘I’m blind, in space, holding a drill. Houston, I have a problem’


Chris Hadfield: ‘I’m blind, in space, holding a drill. Houston, I have a problem’
An extract from Chris Hadfield’s An Astronaut’s Guide To Life On Earth
Chris Hadfield
Fri 25 October 2013
I am calm the night before my first spacewalk in 2001, but I am also conscious I am about to do something I’ve been dreaming of most of my life. I feel ready – I’ve studied and trained for years. Still, I spend hours polishing the visor of my spacesuit so my breath won’t fog it up, unpacking and checking each piece of gear, pre-assembling as much of it as I can, then carefully attaching it to the wall with Velcro. My crewmate Scott Parazynski and I are installing Canadarm2, the robotic arm that will build the International Space Station, currently still in its infancy. We docked our space shuttle, Endeavour, to it a few days before, but haven’t yet been able to open the hatch because our EVA (extravehicular activity, or spacewalk) is going to take place from the shuttle airlock – essentially a depressurised bridge between the two spacecraft.
There are multiple steps to follow for an EVA; mess one up and you won’t make it out of the spaceship. It will be many busy hours until we can float out of the airlock and Nasa has choreographed them down to five-minute slices, even dictating when and what to eat for breakfast: PowerBars and rehydrated grapefruit juice. I shave, wash up (hair-washing involves scrubbing your scalp vigorously with no-rinse shampoo, then drying off carefully to be sure stray wet hairs don’t wind up floating all over the spacecraft and clogging up air filters or eyes and noses) and use the toilet. (You pick up a thing that looks like a DustBuster with a little yellow funnel attached, then hold it up close so you don’t get pee everywhere. I don’t want to have to use my diaper if I can help it.) Then I pull on the liquid cooling garment, which is like long underwear with a lot of personality; it’s full of clear plastic tubing that water flows through, and we can control the temperature. It feels stiff, like a cheap Halloween costume, but when the sun is shining on you in a spacewalk, the fabric of the spacesuit gets extremely hot and personal air-conditioning seems like a fine idea.
Four hours later, Scott and I are finally floating head to toe in our spacesuits, carefully and slowly depressurising the airlock and checking and rechecking the LED displays on our suits to make sure that they are functioning properly and can keep us alive in the vacuum of space. If there is a leak in the suit out there, our lungs will rupture, our eardrums burst, our saliva, sweat and tears boil, and we’ll get the bends. The only good news is that within 10 to 15 seconds we’ll lose consciousness. Lack of oxygen to the brain is what will finish us off.
When the airlock has finally depressurised, I grab the handle on the hatch and turn it – not easily, because nothing in a spacesuit is easy. The hatch is like a manhole, and it has to be removed and stowed in a bike rack-like contraption overhead. My exit will not be graceful. But my number one concern is to avoid floating off into space, so I’m tethered to Scott and I’m holding another tether to attach to the rail on the side of the shuttle. I lower the gold shield on my visor to protect my eyes from the sun and carefully, gingerly, wriggle my bulky suited self out of the airlock. I’m still inside the belly of the beast, in the payload bay, but my suit has become my own personal spaceship, keeping me alive.
Emerging from the bay, my existence narrows to a single point of focus: attaching my tether to the braided wire strung from one end of the vehicle to the other. I lock on to that and tell everyone I’m securely tethered. Now Scott can come and join me. Waiting for him, I check behind me, to be sure I haven’t accidentally activated my backup tank of oxygen, and that’s when I notice the universe. The scale is graphically shocking. The colours, too. The incongruity is stupefying: there I was, inside a small box, but now – how is this possible? What’s coming out of my mouth is a single word: “Wow.” Only elongated: “Wwwooooowww.” My mind is racing, trying to understand an experience that is so unique. It’s like being engrossed in cleaning a pane of glass, then you look over your shoulder and realise you’re hanging off the Empire State Building, Manhattan sprawled vividly beneath. Of course I’d peered through the shuttle windows at the world, but I understood now that I hadn’t seen it, not really. Holding on to the side of a spaceship that’s moving around the Earth at 17,500 miles an hour, I could truly see the astonishing beauty of our planet, the infinite textures and colours. On the other side of me, the black velvet bucket of space, brimming with stars. It’s vast and overwhelming, this visual immersion, and I could drink it in for ever, only here’s Scott, out of the airlock, floating over towards me. We get to work.
After five hours, the installation is going well, albeit slowly, when I become aware of droplets of water floating around inside my helmet. An EVA is incredibly taxing, physically, and over the years we’ve tried putting some sort of food inside the suit so we have something to eat. But it’s been messy and more hindrance than help, so typically we just have a water bag. You bite on the straw to open a valve, then suck out water – hypothetically, anyway. My water bag hasn’t worked since we started the EVA and now it is apparently leaking.
I’m trying to ignore these little globs of water floating in front of my face when suddenly my left eye starts stinging. It feels as if a large piece of grit has been smashed into it. Instinctively I reach up to rub it – and my hand smacks into my visor. “You’re in a spacesuit, moron!” I remind myself. I blink repeatedly and whip my head from side to side to try to dislodge whatever it is, but my eye won’t stay open for more than a blurry second.
We’ve trained for many eventualities during an EVA, but partial blindness is not one of them. I’m tightening the bolts on Canadarm2 using a big handheld drill. My feet are clicked into the foot restraints and my tether is firmly attached to the space station; I’m at no imminent risk. I decide to keep working and tell no one. I move on to the next bolt, but my left eye is now not only smarting but actually filling with tears.

Hadfield at work in orbit. Photograph: Nasa/Newsmakers/Getty Images
Tears need gravity. On Earth, a little duct above your eye generates tears that flush out any irritant, then overflow down your cheek. In weightlessness tears don’t flow downward. They just sit there and, as you keep on crying, a bigger and bigger ball of salty liquid accumulates to form a wobbly bubble on your eyeball. The growing ball of tears in my left eye oozes over, like a burst dam, invading my right. Within just a few minutes, I’ve gone from 20/20 vision to blind. In space. Holding a drill.
“Houston, EV1. I have a problem.” As the words come out, I can picture the reaction on the ground. First there will be concern for me personally and then, seconds later, everyone at Mission Control will be galvanised, tossing out theories about causes and trying to figure out solutions.
To Scott and me, under-reacting seems the best option: I can’t see, but he’s fine and still working on the wiring on another part of the station. I need to get this job done; the Canadian-designed and built Canadarm2 is both a test and proof of our robotics capability. Crew safety is the number one priority, but we can’t just leave this vital piece of equipment flapping off the side of the space station. The EVA is also a big deal back home: no Canadian has ever walked in space before. In other words, it’s not a good time to be having eye trouble.
The focus on the ground is figuring out what’s causing the contamination. They go straight to the worst-case scenario: maybe the problem is related to the air purification system in the spacewalking suit, which relies on lithium hydroxide to remove carbon dioxide. Lithium hydroxide is caustic and can severely damage your lungs; eye irritation is one of the first signs of a leak. So maybe I’m experiencing early symptoms of exposure and have only a couple more minutes to live. Ellen Ochoa, the Nasa “capcom” who’s the voice of Mission Control, calmly tells me to open my purge valve – essentially, open a hole in my suit.
This goes against my survival instincts, but I start dumping my air into space. I listen to the hissing noise as my oxygen merrily burbles out into the universe. It’s a curiously peaceful moment. Without sight, my body is telling me that nothing out of the ordinary is going on. I feel more like I’m under the covers in bed than hanging on to the side of the station, in mortal danger.
The suit has a significant amount of oxygen, enough for eight or even 10 hours, and I also have a secondary O2 tank, so I can bleed oxygen and stay alive for a long time. But who knows how much longer we’ll have to be outside to finish attaching the arm? I start trying everything I can think of to unblind myself: shaking my head around to brush my eyes against something in the helmet, blinking for all I’m worth. I know the doctors on the ground are undoubtedly saying, “We’ve got to bring him inside right this minute and figure out what’s going on.” So I say, “I feel no lung irritation at all and I think my eyes are starting to clear a little bit.” It’s sort of true. I feel marginally less sightless. I keep blinking and thankfully, 20 minutes on, I think I can see well enough to continue.
Nearing the end (almost three hours later), I look down to watch the world pour by. Having overcome this obstacle and knowing the two of us have accomplished what we set out to do is a big moment. But with a spacewalk, the very last step is as important as the first one, so not until we’ve repressurised the airlock and are actually back inside our spaceship do I let myself relax. As soon as I do, I feel completely drained and just float limply, shivering with cold. My body is out of fuel.
Later, as we’re going over the possibilities of what went wrong, the capcom asks, “Chris, did you remember to use your anti-fog stuff?” Of course I had. The night before I’d polished the visor of the suit. “You didn’t get it all off.” Apparently the solution is basically dishwashing detergent; mix it with a few droplets of loose water and it’s as though you’ve squirted soap directly into your eye. A spacewalk with a multimillion-dollar piece of equipment absolutely vital to the construction of the ISS was jeopardised because of a microscopic drop of cleaning solution.
Eventually, Nasa changed the solution to something less noxious. But in the meantime, thanks to my widely publicised oversight, all astronauts knew to be fanatical about wiping down the interior of their visors. Even in my line of work, it’s the small stuff.
I missed my children in space, but no more than I do on the ground, where I don’t see enough of them either. And I missed my wife. But I wasn’t lonely. Loneliness, I think, has very little to do with location. It’s a state of mind. In the centre of every city are some of the loneliest people in the world. If anything, because our whole planet was just outside the window, I felt even more aware of and connected to the seven billion other people who call it home.

Permanent link to this article: https://animatedscience.co.uk/2013/chris-hadfield-im-blind-in-space-holding-a-drill-houston-i-have-a-problem

What are Maxwell’s Equations?

What are Maxwell’s Equations?


Permanent link to this article: https://animatedscience.co.uk/2013/what-are-maxwells-equations-2

The Higgs boson particle – digested

The Higgs boson particle – digested


The Higgs boson particle – digested
The secret of life and the universe, explained by our science editor

An experimental result in the search for the Higgs boson particle, released by Cern.

In the aftermath of the big bang that flung the universe into existence 13.82bn years ago, the forces of nature were one. But as the universe expanded and cooled, they separated out into the four seen today. The electromagnetic force, which is carried by photons, allows you to see, and stops you falling through your chair.

The strong force holds atomic nuclei together. The weak force goes to work in the sun and helps to make it shine. Then there is gravity, which is not really a force at all, but that is for another time.

One trillionth of a second after the big bang, an invisible field that spread throughout space switched on. This Higgs field wrenched two intertwined forces apart – the weak force and the electromagnetic force. How? By making the particles that carry the weak force heavy, while leaving the photon weightless.

The weak force travels less than the width of an atom, but the electromagnetic force ranges over an infinite distance.

The Higgs field gives mass to other particles too, such as quarks and electrons, the building blocks of atoms. The Higgs boson comes with the field, a subatomic smoking gun that proves the field is there.

Permanent link to this article: https://animatedscience.co.uk/2013/the-higgs-boson-particle-digested

Queensland solarium ban will save lives, Cancer Council says

Queensland solarium ban will save lives, Cancer Council says


Permanent link to this article: https://animatedscience.co.uk/2013/queensland-solarium-ban-will-save-lives-cancer-council-says

How to write a personal statement for history

How to write a personal ucas statement for history


History is the tenth most popular subject to study at degree level in the UK, and with many universities forgoing candidate interviews, your personal statement is the most important way to make yourself stand out. The competition is fierce (the top universities require grades of A*AA), and a muddled or mediocre statement will harm your application.

So how can would-be historians impress application tutors? Dr Elizabeth Tingle, of Plymouth University, wants the statement to reflect the candidate who wrote it. She says: “When we talk about originality inpersonal statements, we really mean individuality.”

Southampton University’s Dr McHugh agrees that many applications are “too generic and vague. We want to get a sense of who you are as an individual, and what kind of student you would be.”

This individuality should not be achieved through wild or outrageous methods; your statement doesn’t need to be written in old English, or abstractly represent the consciousness of Thomas Cromwell. If you do something outrageously different, there’s probably a reason why no one’s done it before.

Instead, a personal statement should show something of you as a person, and convey your own unique engagement with history. Dr Ryrie, historian of religion at Durham says:

“The kind of personal statement that warms an admissions tutor’s heart is the kind which is honest: which describes, in genuinely personal terms, quite why the student loves the subject, and conveys something of their passion for it”.

‘Passion’, however, is a controversial word. UCL’s Dr Jason Peacey complained that “it gets a bit tiring reading hundreds of forms where the student proclaims that they have a ‘passion’ for history”.

Dr Ansari, head of history at Royal Holloway, agrees, and wants “genuine expressions of interest in history, but not in terms of ‘I am passionate about…’. Simply wanting something strongly is not enough”.

You need to convince admissions tutors that you have the intelligence and academic ability needed to successfully undertake a degree in the subject.

Dr Peacey says: “Students don’t always do enough to explain what it is about history that interests them, why this interest can only be met by undertaking more study at a higher level, and what should make me think that they have the potential and ability to study at this level”.

The same sentiments are also mentioned by Dr McGladdery, admissions officer at St Andrews. “Studying and writing about what happened in the past has little purpose if students cannot develop the skill of critical evaluation. Historiographical awareness is very important, as is the ability to present an opinion supported with evidence and cogent analysis.”

Students who show that they have considered the subject in relation to other academic avenues are likely to impress. As Dr Gadja, of Oxford university, says:

“Historians like to take insight from a huge range of perspectives, so we are always delighted when students can demonstrate how their interest and ability at foreign languages, philosophy, or political thought, literature, and so on, might intersect with their historical interests, and be of use in their development as historians”.

A clear, competent analysis of the ways in which your different subjects interact, and how this has aided your ability as a history student, can be a valuable inclusion in your personal statement.

Dr Gadja says that it is important to mention extra-curriculur interests. For Gadja, an interest in visiting museums, going to public lectures, and anything that shows an interest in history beyond the demands of one’s A-level course, would be relevant.

If you have had any relevant work experience, do mention it, but it must have had a definite impact on your approach to thinking about history. If you haven’t managed to gain experience in a historical field, though, don’t worry too much.

Gadja says: “we certainly don’t look for relevant work experience when making decisions – most applicants will not have had the fortunate opportunity to work in jobs relating to the heritage industry or similar, and that doesn’t put them at a disadvantage at all”.

Mention of non-academic areas in which you are wonderfully talented should be limited to a couple of sentences at most, and should always be linked back to the ways in which they have contributed to your academic or personal development; such as by improving time-management, or organisational skills.

Dr Simon Smith, of Oxford University, say: “Unlike some US universities or colleges, UK universities are not seeking to admit quotas of musicians, sports people, or thespians.”

It is important to write the statement in clear, concise prose, avoiding the use of formulaic words or phrases. Dr Peacey says:

“If I had a pound for every time I had been told that history is important because, as George Santayana said, those who fail to understand the mistakes of the past will merely repeat them… then I would be a rich man indeed.”

Try and avoid stilted references to the “eternal value” and “enduring fascination” of the past. Far more impressive is to explain and analyse what it is that makes you so interested in history, and specific areas in particular.

Above all, you should engage with the concepts that you are discussing, rather than just stating them. As Dr Ryrie says:

“Make us feel that you are a person of vision and imagination, for whom your outstanding A-level performance is just the beginning.”

Avoid anything bland or dull, and make the personal statement a reflection of your individual talents and interests. You want your statement to be different and engaging, otherwise it will slip through admissions tutors’ fingers without leaving a mark.

Permanent link to this article: https://animatedscience.co.uk/2013/how-to-write-a-personal-statement-for-history

Meteorite pulled from Russian lake

Meteorite pulled from Russian lake http://www.bbc.co.uk/news/science-environment-24550941

Permanent link to this article: https://animatedscience.co.uk/2013/meteorite-pulled-from-russian-lake

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