Orion’s first flight is good news – but can NASA sell the space dream?

I checked the latest space news on Saturday with bated breath. NASA had a lot riding on this week’s Orion flight. In a climate of limited budgets and little real public enthusiasm, failure wasn’t an option.

Artists' impression of the Orion EFT-1 mission. NASA, public domain.

Artists’ impression of the Orion EFT-1 mission. NASA, public domain.

The problem is where Orion goes next. By Cold War standards ambitions are vague; a couple more test flights, fly around the Moon or go to a captured asteroid by 2021-25, and then on to Mars some stage in the 2030s….eventually. Maybe. Both these aims and the time-frame stand at odds with Apollo-era determination when goals, budgets, public support and intent all meshed. I wouldn’t be surprised if Orion flounders before it gets much further, purely because of that mushiness vs public apathy vs budgetary realities.

Which is a pity, because it’s a good spacecraft and the flight on Saturday demonstrated – after two tragic ‘private enterprise’ failures – that the Apollo-era NASA ‘business model’, which rested on private contractors and commercial suppliers – still works. Rocket science is just that – it’s risky, difficult, and stretches materials science. Cutting corners, private-enterprise style, may save money. But when it comes to spaceflight there’s no room for error.

EFT-1 Orion being prepared to flight atop a Delta 4 Heavy. NASA, public domain.

EFT-1 Orion being prepared to flight atop a Delta 4 Heavy. NASA, public domain.

The other point is that Orion is not – as some critics suggest – a retrograde step. Sure, Orion looks like a 1960s capsule. But it isn’t – it’s stuffed with twenty-first century tech. Don’t be fooled by its 2002-era PowerPC 750FX-based computers, either; space computer hardware has to be well proven and rugged. If it fails at the wrong moment, you die. Armstrong and Aldrin’s Raytheon AGC fly-by-wire computer partly crashed when they were descending to the Moon in 1969. But not totally – and it was safe to land.

What’s driving the illusion of Orion being ‘retrograde’, I think, is that we’re conditioned to imagine space ‘progress’ as ‘advance’ from one-shot cone-shaped ‘capsules’, to multi-use winged spaceplanes designed to fly, literally, into space. They were the future, way back when. Except they weren’t. The problem is that the laws of physics don’t co-operate. Mass is everything in spaceflight – dry mass to fuel mass ratio, in particular. The Shuttle orbiter had to lug a LOT of mass into orbit that was useless up there – wings, tail, landing gear, hydraulics, heat shield and so forth. Dead loss for your fuel budget. And that’s apart from the risks of strapping the spaceplane to the side of its booster.

Orion recovered off California after the flight, 4 December 2014. NASA, public domain.

Orion recovered off California after the flight, 4 December 2014. NASA, public domain.

For anything beyond low-earth orbit, you need a vehicle that lacks the encumbrance of aircraft-style flight hardware – but which can still make an aero-braked descent to Earth, because it’s not practical to carry the fuel you need to slow down by rocket. Ideally the spacecraft also has to generate a certain amount of aerodynamic lift, both to steer the descent and to reduce deceleration forces on the crew. The resulting shape is specific, and Apollo, Orion, the Boeing CST-100 and Chelomei’s 1970s-Soviet era VA re-entry capsule all use virtually the same truncated cone design. McDonnell Douglas’ Gemini, Space X’s Dragon, the Soyuz and Shenzhou offer only minor variations on the theme.

Apollo vs Orion. NASA, public domain.

Apollo vs Orion. NASA, public domain.

Orion, in short, is a recognition of the physics of rocket-propelled spaceflight. Budgets permitting, the 2020s should bring a flurry of similar spacecraft into low-earth orbit – Space X’s Dragon and Boeing’s CST-100, servicing the space station. The Russians (hopefully) will be in on the mix with their late-generation Soyuz. And there’s the Chinese manned programme.

Cut-away of the modified Apollo/SIVB 'wet lab' configuration for the 1973-74 Venus flyby. NASA, public domain, via Wikipedia.

Cut-away of the modified Apollo/SIVB for the 1973-74 Venus flyby. NASA, public domain.

Beyond that, Orion will be on hand to fly to the Moon, a nearby asteroid, and eventually Mars. Orion will not, of course, fly by itself on long-duration missions. It’s good for 21 days in space – enough for an Apollo-type jaunt around the Moon – but for longer flights it’ll be docked to a habitat module. This mirrors the 1968 plan to send astronauts on a Venus flyby using Apollo hardware – the crew would have spent most of the 396 day flight inside a modified S-IVB stage, using the CSM only for the launch and re-entry phases.

Orion with propulsion and habitat module for an asteroid mission. NASA, public domain.

Artist’s impression of Orion with propulsion and small habitat module for an asteroid mission. NASA, public domain.

Orion, similarly, will be docked with various habitats and propulsion stages depending on mission. The whole stack will become the ‘interplanetary spacecraft’. But all this assumes budget and enthusiasm, among other things (‘other things’ includes finding ways of dealing with radiation, of which more some other time). Bottom line is that state-run space efforts can be killed with the stroke of a political pen.

Perhaps the biggest challenge, then, will be re-selling the excitement of the space dream to a wider public, both in the US and beyond. And this, I think, is where the focus needs to be for the foreseeable future. Space flight is, after all, one of the greatest ventures in the history of the world.

Copyright © Matthew Wright 2014

The really annoying thing about time travel stories

I’ve always wanted to invent a time machine so I could whip back in time to stop Hitler before he did anything evil. Of course there are a couple of problems. First is I’d be joining the back of a LOOONG queue. The other is that our friend Albert Einstein tells us it’s impossible.

But even if a time machine could be built, nobody’s really figured out what it entails. Here’s the deal.

The Horsehead nebula, Barnard 33, as seen by Hubble. Wonderful, wonderful imagery.

The Horsehead nebula, Barnard 33, as seen by Hubble. Wonderful, wonderful imagery.

Science fiction is rife with stories about time travel, variously either as social commentary, H. G. Wells style, or as cautionary tales – witness Ray Bradbury’s wonderful A Sound of Thunder. Invent a time machine, go back in time and change the past – and you’d better watch out.

Of course, if things change so you don’t exist, then you can’t have invented the time machine. Which means you didn’t go back in time. Therefore you do exist, so you did invent the time machine and… Yah.

Or there’s Harry Harrison’s hilarious Technicolour Time Machine, about a movie maker who uses a time machine to cut production costs on his period drama by going back to the actual period. What I’m getting at is that there’s a gaping great hole in all of this. And it’s an obvious one.

Suppose you COULD time travel. Suppose you’d built a machine to do it. You decide to whip back twelve hours. And promptly choke to death in the vacuum of deep space.

Nikolai Tesla with some of his gear in action. Public domain, from http://www.sciencebuzz.org/ blog/monument-nearly-forgotten-genius-sought

OK, so it’s not a time machine, but this is what one SHOULD look like. Nikolai Tesla, being spectacular with AC electricity (he’s reading a book, centre left). Public domain, from http://www.sciencebuzz.org/ blog/monument-nearly-forgotten-genius-sought

What gives? The problem is that everything in space is moving. Earth is rotating. Earth also moves around the Sun, which itself is orbiting the galaxy, which itself is moving as part of the Local Group, and so forth. We don’t notice or even think about it because we’re moving with the Earth. If we take Earth as our reference point, it’s fixed relative to us. And that leads us to imagine that  time machines are NOT moving through space – Wells, in particular, was quite explicit that his time machine was fixed and time moved around it.

But actually, a time machine that did this – that stayed ‘still’ relative to Earth would have to move through space, because Earth is moving.

Let’s reverse that for a moment. What say your time machine doesn’t move in space at all. You move back and forth through time, but your absolute spatial position is fixed. Not relative to Earth, but relative to the universe.

You leave your lab and leap back 12 hours. Earth won’t be there – it won’t have arrived. Leap forward 12 hours – same thing, only Earth’s moved away. If you’ve only moved a few seconds, you might find yourself plunging from a great height (aaaargh!). Or buried deep in the Earth (choke).

So for a compelling time-machine story you need to have a machine that not only travels anywhere in time, but also anywhere in space. And, of course, any relative dimensions associated with both. That’s right. A machine that travels anywhere through time and relative dimensions in space.

Heeeeeey, wait a minute

Copyright © Matthew Wright 2014

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Why this week’s comet landing is way better than celebrity butt-fests

This week’s landing on Comet 67P/Churyumov-Gerasimenko was a landmark in space history – not because the comet apparently bore a passing resemblance to the Kardashian backside that was competing for place in the news, but because surface gravity on 67P is about one millionth Earth’s. You don’t land so much as drift in and try like hell to stay there.

Potential landing sites on the double-lobed Comet 67P/Churyumov-Gerasimenko. Copyright ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Potential landing sites on the double-lobed Comet 67P/Churyumov-Gerasimenko. Copyright ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Add to that the fact that the cometary surface is like a rugged boulder-field and you have a recipe for Ultimate Challenge. That’s what made the landing so risky – and why ESA’s Philae lander was equipped with harpoons, ice-screws, and a down-firing thruster. When they failed, Philae landed on the comet, then bounced a kilometre back into space before the comet’s lazy gravity pulled it back. It was also a funny sort of bounce because the comet isn’t a sphere – it’s more like a dumb-bell. When Philae came down a second time, it bounced again before eventually settling.

For me the three-bounce landing (at 15:34, 17:25 and 17:32 GMT on 12 November) has a wow factor well beyond landing on a comet for the first time e-v-a-h. It’s also about gravity – and that means it’s about Einstein, one of my favourite physicists. Let me explain. Gravity doesn’t just cause celebrity butt-sag, after a while. It’s also why the comet’s where it is today. Fact is that 67P/Churyumov-Gerasimenko experienced a gravitationally-driven orbit change in 1959, when an encounter with Jupiter dropped its perehelion (closest approach to the Sun) from 2.7 to 1.3 astronomical units, giving the comet its current 6.45 year period. That’s why it’s where it is now.

Gravity is also how ESA got the probe to the comet. It was boosted, during a decade-long journey, by gravity assist manoeuvres, swing-bys of Earth and Mars that exploited space-time curvatures around the planets to accelerate the probe (three times) and decelerate it (once), without burning a single gram of fuel.

Ain’t physics neat. So just what is gravity? This looks like a stupid question. Actually, it isn’t.

Rosetta's long odyssey to the comet - with slingshot gravity boosts from Earth and a de-boost from Mars. NASA, public domain.

Rosetta’s long odyssey to the comet – with slingshot gravity boosts from Earth and a de-boost from Mars. NASA, public domain.

The thing is, we think of gravity as a ‘force’. But actually, according to Einstein, it isn’t. We just perceive it as such. Here’s why. Science started looking at gravity in earnest when all-round super-geek Sir Isaac Newton worked out the math for the way gravity presented in everyday terms, which he published as part of his Philosophiæ Naturalis Principia Mathematica in 1687. His gravitational theory worked (and still works) well at everyday level – you could calculate how apples might fall, figure out planetary movements and so on (the key equation is    F = G \frac{m_1 m_2}{r^2}\ , which defines the force between two point-sources of defined mass.) Newton’s triumph came in 1838 when astronomers realised that Uranus wasn’t quite where it should have been, based on the tugs of the known planets. French mathematician Urbain Leverrier and British mathematician John Couch Adams, independently, reverse-engineered the data to pinpoint where an unknown planet should be – and sure enough, there it was. Neptune.

Albert Einstein lecturing in 1921 - after he'd published both the Special and General Theories of Relativity. Public domain, via Wikimedia Commons.

Albert Einstein lecturing in 1921 – after he’d published both the Special and General Theories of Relativity. Public domain, via Wikimedia Commons.

But as science began fielding more data, it became evident that Newton’s equations didn’t account for everything – which is where Albert Einstein comes in. His General Theory of Relativity, published in 1917, is actually a theory of gravity. General Relativity supersedes Newton’s theory and portrays gravity by a totally different paradigm. To Newton, gravity was a force associated with mass. To Einstein, gravity was not a force directly innate to mass, but a product of the distortion of space-time caused by mass/energy, which bent the otherwise straight paths of particles (‘wavicles’), including light.

The proof came in May 1919 when British astronomer Sir Arthur Eddington measured the position of Mercury during a solar eclipse. Mercury’s perehelion – the closest point to the Sun – precessed (moved) in ways Newton couldn’t account for. Einstein could – and the planet turned up at precisely the place general relativity predicted. Voila – general relativity empirically proven for the first time. I don’t expect that Einstein leaped around going ‘woohoo’, but I probably would have. And general relativity has been proven many, many times since, in many different ways – not least through the GPS system, which has to account for it in order to work, because space-time distortion also causes time dilation. (If you want to live longer, relative to people at sea level, live atop a mountain).

Einstein’s key field equation, as it eventually evolved, is G_{\mu\nu}\equiv R_{\mu\nu} - {\textstyle 1 \over 2}R\,g_{\mu\nu} = {8 \pi G \over c^4} T_{\mu\nu}\, – which I am not going to explain other than to point out that it could be used to calculate the space-time distortion caused by the mass of, say, a Kardashian butt. This would be a hideous waste of brain-power, but at least means I’ve managed to put both Einstein’s field equation and a reference to society’s shallow obsession de jour in the same sentence. As an aside, I also think Einstein got things right in more ways than we know. I don’t say this idly.

Philae lander departing the Rosetta probe for its historic rendezvous with the comet. Copyright ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Philae departing the Rosetta probe for its historic rendezvous with the comet. Taken by the orbiter’s OSIRIS camera. Copyright ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

One of the key things about both Newton and Einstein is that their theories treated clumps of particles – a mass such as the Earth for instance – as if the gravity originated in a mathematical point at the centre of the mass, even though the gravity (‘space-time distortion’) is produced by every particle within that mass. And that works perfectly at distance. But in detail an uneven distribution of mass –  a mountain range, for instance, or even a celebrity butt – can introduce local pertubations. Small – but calculable. It’s because of ‘mass concentrations’ that satellites we put around the Moon eventually crash, for instance.

Which brings me back to the science adventure on 67P/Churyumov-Gerasimenko, 28 light-minutes away outside the orbit of Mars. With a long-axis diameter of around 5 km and a composition of loose rocks held together by ices, 67P/Churyumov-Gerasimenko doesn’t have enough mass to bend space-time much. It has, in short, almost no gravity. Orbiting it, as Rosetta has been doing since 6 August, is more like a lazy drift around it. To land is more akin to docking than anything else. There’s not a lot to hold Philae ‘down’, and it doesn’t take much to bounce off. To that we have to add the dumb-bell shape of the comet’s nucleus, which produces complex (if gentle) space-time curvatures, meaning a ‘bounce’ on the comet isn’t going to be a simple parabola like a ‘bounce’ on Earth.

All of which underscores the tremendous technical achievement of the landing – bounces and all. The final lesson? Don’t bother with celebrity butt. Einstein and comets are FAR more interesting.

Copyright © Matthew Wright 2014

Is Comet Siding Spring going to turn our Mars probes into shredded tinfoil?

Shiver in your shoes, Martians! This month – specifically, 19 October at 18:28 Zulu – Comet C/2013 A1 ‘Siding Spring’ makes its closest approach to Mars. The nucleus, a few kilometres in diameter, will come a smidgeon under 120,000km from the red planet.

Mars from the Siding Spring nucleus at closest approach - a picture I made with my trusty Celestia astronomy package.

Mars from the Siding Spring nucleus at closest approach – a picture I made with my trusty Celestia astronomy package.

That’s close. Though not as close as once feared. When the comet was first discovered by Robert H. McNaught in January 2013, using the 20-inch Upssala Schmit telescope at Siding Spring observatory in New South Wales, it was thought likely to hit Mars. It was only later, after multiple observations and cross-checks, that the orbit was refined.

Good news is that this is a tremendous opportunity – and there’s a fleet of orbiting satellites up there for the purpose.  Two, the US MAVEN and India’s Mars Orbit Mission (MOM) – arrived just last week. That puts a lot of instruments in close proximity, and the Indians have plans to use MOM to check for methane on the comet as it brushes past. The Mars Reconnaissance Orbiter will use its HIRISE camera to look at the comet nucleus and activity. Mars Odyssey will check out the coma. MAVEN will make a range of observations with eight different instruments. Even the rovers on the ground, Curiosity and Opportunity, will point their cameras at the sky – Curiosity’s ChemCam, which can pick up the composition; and Opportunity’s PanCam, which will give us a visual from the surface of Mars.

More shenanigans from my Celestia software. This is a view looking from inside the coma towards Mars and the Sun at closest approach.

More shenanigans from my Celestia software. This is a view looking from inside the coma towards Mars and the Sun at closest approach.

Bad news is that this fleet of satellites took years to get up there, cost billions of dollars – and are basically irreplaceable. The nucleus won’t get near Mars. But the coma of dust and debris surrounding it will. Estimates are that during the several hours it takes Mars to pass through the comet’s coma, the planet will be peppered with about five years’ worth of normal meteor activity. It’s all small stuff – nothing more than 1cm diameter, most of them only fractions of a millimetre. But the relative speed is 56 km/sec (200,000 km/h). That’s – uh – impressive. At that speed a 1 gram mass has a kinetic energy of 15,680,000 joules, or 4.35 kwH. In human terms? Enough to run a domestic fan heater on high for a couple of hours. Woah! And that’s just one particle. There are going to be a LOT of particles skidding past Mars.

More Celestia fun; a picture I made of planetary orbits at the moment of Siding Spring's Mars encounter.

More Celestia fun; a picture I made of planetary orbits at the moment of Siding Spring’s Mars encounter.

Precautions have included adjusting orbits so the probes will be on the opposite side of the planet from the comet 100 minutes after closest encounter, when the dust is estimated to reach its highest density. The MRO shifted its orbital parameters to that end on 2 July, while Odyssey did so on 5 August and MAVEN on 9 October. Still, that’s not a complete fix – they’ll travel back around into the danger zone soon enough. Other precautions include pointing the spacecraft so more delicate components are shielded by less crucial elements. And MAVEN will be put into a partial shut-down mode. Once the danger’s past, they’ll restart the science.

By 22 October, according to mission timelines, it’ll all be over. And, if the cometary debris hasn’t shredded them into tinfoil, they’ll be back to their normal work exploring the red planet.

Is Earth in any danger? None whatsoever. Even if we were at closest approach to Mars, the comet wouldn’t affect us – but as it happens, we’re nearly a quarter-turn away from Mars in any case, just at the moment. That’s not the issue – the issue is the several billion dollars worth of science equipment we’ve got around Mars at the moment, its survival – and the science we’ll get from them during this once-in-a-lifetime opportunity.

Copyright © Matthew Wright 2014

Close encounters of the meteor kind – this weekend

Back in 2013, I wrote a piece that mashed Pope Benedict’s resignation with the science of the meteorite that exploded over Russia. I was Freshly Pressed by WordPress on the back of it. Good stuff.

The fly-by. NASA, public domain. Click to enlarge.

The fly-by. NASA, public domain. Click to enlarge.

This weekend, a similarly sized chunk of space debris – about 20 metres in diameter – is rolling past Earth with closest approach of just 40,200 km, directly over New Zealand, at 6.18 am on Monday 8 September, NZT (18:18 Zulu, 7 September).

I use the word rolling deliberately. Everything spins in space.

The meteor’s called 20214 RC (R-C) and was detected only on 31 August by the Catalina Sky Survey at Tucson, Arizona. And that raises a point. The spectre of Earth being clobbered by even a modest piece of space detritus has haunted science for decades. Right now, we’re doing something about that – scanning near-Earth space in a hunt for likely impactors.

The orbit. NASA, public domain. Click to enlarge.

The orbit. NASA, public domain. Click to enlarge.

What we’d do if we found such a thing, other than despatch Bruce Willis, isn’t clear. Nuking them isn’t an option – the evidence is growing that some of these space rocks are just clumps of loose-ish ice and dirt. In any case, you’d end up with a cloud of debris, still hurtling for Earth and still able to deliver virtually the same kinetic blow to the planet. Personally I think we should splash one side of any likely impactor with black paint, but that method (which exploits asymmetric re-radiation of absorbed thermal energy) requires several years’ warning. This new encounter comes just a week after discovery – with all that this implies.

There’s no danger from 20214 RC (R-C). It’s got an orbital period of just over 541.11 days, which is different enough from Earth’s to mean there won’t be another encounter any time soon. But one day the orbital mechanics will mesh and it’ll be back in our vicinity. It won’t be an impact danger. But we don’t know what else is out there.

Yup, you’ve got it. That old sci-fi doom scenario involving a meteor suddenly sloshing the Atlantic into the US Eastern Seaboard and Europe? It’s baaaack…

Copyright © Matthew Wright 2014

Star Trek lessons – writing out of the box

I’ve long thought most of the Star Trek franchise series and movies – the ones made between 1977 and 2005 – to be epic fails both as good SF and, more to the point, as good dramatic story-telling.

Sounds heretical, and I suppose I’ll get heat from fans – but if you step back to the first principles of writing, it’s true. I’ve just finished reading a book by Brian Robb, Star Trek: The essential history of the classic TV series and movies, which confirms my belief.

Eta Carinae. NASA, public domain. Click to enlarge.
Eta Carinae. NASA, public domain. Click to enlarge.

I’m not complaining about the fact that Trek aliens all looked like humans with lobsters glued to their foreheads or that Klingon was apparently constructed to be different rather than linguistic by the usual measures. My problem goes deeper than that.

Robb argued that the best ideas of the original 1966-69 series – the things fans regard as canonical – weren’t created by Gene Roddenberry. But he had huge influence and one major legacy was a set of rules about what could and could not happen. Writers called it the ‘Roddenberry Box’.

This defined Roddenberry’s vision – a future that had conquered prejudice, where inter-personal conflict was a thing of the past. A wonderful ideal. One we should aspire to. The problem was that when it came to story-telling, the Box was boring. A lot of the challenge for writers was getting around the limits while producing interesting tales.

To my mind that worked in the original series, particularly where the show was run as a light comedy – think Trouble With Tribbles. Wonderful. Why did it work? Because Roddenberry hired great writers – top-line SF authors among them – to work up plots revolving around three great characters, Spock, Kirk and McCoy.

'That's no moon'. Wait - yes it is. It's Mimas, orbiting Saturn.

‘That’s no moon’. Oops – wrong franchise. Actually, this is Mimas, orbiting Saturn. NASA, public domain

The problem – well explored by Ross, but which I’d long thought true – is that the show was captured by a fan base for whom the Box defined canon. To me the rot set in with The New Generation, which mashed New Age thinking and a lot of meaningless techno-babble with the Box and – to me – never captured the sense of wonder of the original. It was pretentious, laboured, ponderous, and fast descended to reverent posturing by one-dimensional characters – stories defined not by what made a good story, but by what was needed to satisfy a fan base.

I gave up watching it, and never bothered with Deep Space Nine or Voyager. I gave up on the movies. Later I caught a few episodes of Enterprise, which wasn’t too bad but which still dribbled, as far as I was concerned. According to Robb, the producers were actively writing, by then, for fans – missing a wider audience or new fans. Certainly, these grotesque going-through-the-motions exercises in franchise fodder didn’t appeal to casual Trek enthusiasts, like me.

For me, Trek didn’t come right until the 2009 J J Abrams movie, a complete re-boot which decisively broke the Box. It was Trek as it should be, re-cast for the twenty-first century. Wonderful stuff.

The fact that it featured Karl Urban – a Kiwi actor from my city, Wellington, was a particular plus.

The take-home lesson for writers? Idealism is wonderful. There is no faulting Roddenberry’s optimistic vision. But to make interesting stories, that idealism has to be given a dynamic. The fact is that human realities, including conflict, have been omnipresent through history, and it’s unlikely that a few hundred years will change them. But that doesn’t stop us trying; and it seems to me that stories built around the attempt would be far more interesting than stories exploring the success of meeting this hardest of all human challenges.

Your thoughts?

Copyright © Matthew Wright 2014

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Beware the next Carrington storm – a Q&A wrap-up

After last week’s post on a Carrington storm – a solar event able to do large-scale damage to anything electrical, especially power grids. I fielded a few questions which deserved a post. And I had some new ones of my own…

Does the whole Earth get hit?
The issue isn’t the Coronal Mass Ejection that goes with the flare, but the magnetic storm the CME provokes when it hits us. This affects the whole Earth in one hit, because the Sun-side of Earth’s magnetic field is pushed. The shadow side is pulled and zings back. Here’s an animation:

How powerful are these geomagnetic storms?
It depends on the CME, which – don’t forget – is super-hot plasma. The biggest can mass up to 100,000,000 tonnes, moving at up to 1000 km/second. These can really bang into our magnetic field. The current the geomagnetic storm induces in conductive material on Earth will vary as a result of the speed of the field movement, and of the scale of the conductive material. This acts like an aerial, so the more conductive material, the higher the voltages and current induced in it. That’s why the power grid is vulnerable, because transmission lines act as aerials and transformers have copper windings.

A large solar flare observed on 8 September 2010 by NASA's Solar Dynamics Observatory. Public Domain, NASA.

A large solar flare observed on 8 September 2010 by NASA’s Solar Dynamics Observatory. Public Domain, NASA.

Can the excess voltages be calculated?
The voltage generated in a conductor is a product of the rate of change of magnetic flux and the direction of the field lines relative to the conductive material. In a closed loop like a transformer, for instance, this voltage can be calculated by Faraday’s Law of Induction, via James Clerk Maxwell, which states that the negative of the rate of change is equal to the line integral of the electric field. This is a bit of math that quantifies results when direction and intensity are both changing.

Will a geomagnetic storm burn out all power grids?
It depends on the loading of the grid and on the intensity of the storm, which will differ from place to place because the rate of change and flux direction keep changing. A heavily loaded power grid is more vulnerable because it’s operating closer to its designed tolerances. Needless to say, in this age of engineering to cost, some grids are fully loaded in normal operation. That’s why even the modest geomagnetic storms of in the last few decades have sometimes generated localised blackouts – some grids were vulnerable when others weren’t. With a big enough geomagnetic storm, all power grids would be blown out.

OK, so I'm a geek. Today anyway. From the left: laptop, i7 4771 desktop, i7 860 desktop.

OK, so I’m a geek. Today anyway.

What about domestic appliances – computers, hand-helds and so forth?
It depends on the intensity of the storm. Anything plugged into the mains would suffer a voltage spike. Your stove or kettle wouldn’t notice it. Your computer might lock up. A re-boot might fix it, if the power stayed on. Or gear might be physically damaged. Newer devices are more vulnerable than old, partly because the older stuff was over-engineered. Anything with looped wire in it, like an electric motor – which includes DVD drives – might be at risk. Just about everything relies on low-voltage CPU’s these days, including cars, and it’s possible a really big geomagnetic storm would damage some of these. The effects probably wouldn’t be consistent across all gear because there are so many variables in electrical hardware, including whether it’s operating or not when the storm hits.

So some stuff, like the old Morrie Thou every Kiwi wishes they never got rid of, would still work and we’d otherwise mostly be OK?
Don’t forget, there won’t be any mains power, possibly not for months. No water pumps. No sewerage pumps. No heat. No light. No cooking. No battery charging. Hospitals out of action just when needed. Shall I go on?

Please don’t. Will the storm induce current in anything else?
Gas and oil pipelines. Older plumbing. They’re metal too.

Sounds scary. Is there anything we can do?
NASA has satellites on solar weather watch. They’re also implementing Solar Shield, an early-warning project. Whether anybody pays attention to warnings, or even hears them, is another matter. Even if the warning’s broadcast, who listens to dumb science stuff when the rugby news is about to start? But if you hear a warning, turn everything off, keep things unplugged, get your emergency kit stocked with food and water, buy a can opener, dig a long drop, and so on.

Is there a plus side?
We’d get amazing aurora displays towards the equator. Would that compensate for the damage? Uh…no.

Copyright © Matthew Wright 2014