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

Finding another Earth isn’t easy. Unfortunately.

Are you looking for a second Earth? We need to – humanity is on the fast track to ruining our one.

Simulated Exo-Earth. A picture I made. Apart from the fractal artefacts, does anybody notice what's wrong with it?

Simulated Exo-Earth. A picture I made. Apart from the fractal artefacts, does anybody notice the science issue that I didn’t correct?

Of course it’s not an easy task. A planet discovered the other week with the help of Kiwi astronomers underlines the problems. Four astronomers here in New Zealand contributed data to the OGLE microlensing follow-up network program in 2012. The results were published recently – and the good news is, OGLE found a planet.

OGLE, incidentally, stands for ‘Optical Gravitational Lensing Experiment’. An apt acronym. It works by exploiting a quirk of Einstein’s theory of relativity – that mass distorts space-time. Massive stars bend light around themselves, acting as ‘lenses’ and enabling us to point a telescope at the massive star, and so detect faint objects passing directly between us and them, that we wouldn’t otherwise be able to observe. The gravity lens around the distant star is known as an ‘Einstein Ring’, and the method is usually used to pick up planets orbiting in the ‘halo’ of a star – the debris orbiting it, like our Oort Cloud. These are known as Massive Compact Halo Objects (MACHOS). Cool or what?

Anyhow, back to the news. The planet is called OGLE-2013-BLG-0341LBb, and it’s about 3000 light years away in the constellation Cassiopeia.

The good news?

- It orbits its sun at 0.8 AU – nearly the distance of Earth (yay!)

- It’s about Earth sized – mass is thought to be only twice ours (yay!)

- That doesn’t imply twice our surface gravity (yay!) [I can't calculate it unless I know the radius and density of the planet, which I don't, but if density is the same as Earth, average 5.5 g cm <exp>3, then the surface gravity won't be double because surface gravity is also proportional to the radius. Just saying.]

- It’s orbiting just one star in a binary pair (Tattooine, sort of – yay!)

Let me illustrate mass vs surface gravity. Although it has a mass 14.5 times that of Earth, 'surface gravity' on Uranus is just  89 percent that of Earth. That's because the radius is about 4 times Earth's. I made this picture with Celestia.

Let me use Uranus to illustrate mass vs surface gravity. Although it has a mass 14.5 times that of Earth, ‘surface gravity’ on Uranus is just 89 percent that of Earth. That’s because the radius is about 4 times Earth’s. I made this picture with Celestia.

So is this Earth 2? Well, if I were you I’d take warm clothes. The bad news is that the star is a red dwarf, 400 times less energetic than the Sun, so the planet has a surface temperature of 60 degrees Kelvin – in centigrade, a chilly -210 degrees. (Booooo!)

The search for Earth-like planets has got exciting lately as we’ve developed the tech to discover them. Problem is, the gear is not good enough to image them directly. We can’t learn much other than the size and orbital distance – from which we can derive its year, mass and temperature. If we’re lucky, we might also get a handle on its atmospheric makeup, via spectrography as it transits its sun.

For these reasons, usually when we detect a planet that’s otherwise in the ‘goldilocks’ zone, we don’t know whether it’s actually like Earth. It might be like Venus – runaway greenhouse with sulphuric acid, crushing atmosphere and oven-like temperatures. We don’t know. Don’t forget, if astronomers 3000 light years away were using the same techniques to analyse our solar system, they might conclude there were two Earths here from the planetary mass and orbital data.

The way things are going, of course, we’re likely to end up with two Venuses. Venuses? Venii? You know what I mean.

And it’s a worry.

Copyright © Matthew Wright 2014

Ever get that feeling of quake deja vu?

Monday was the provincial anniversary holiday in Wellington, New Zealand. Kind of cool – the provinces were abolished in 1876, but we still get the holiday.

Around 4 pm the house began shaking – slowly at first and then quite violently. We get a lot of small quakes. This wasn’t one of them. In fact, it seemed up there with last year’s big quakes.

The science behind it is fascinating. New Zealand has an automated seismic network that publishes estimated figures to the internet in near-real time. The first official figures – calculated by the duty seismologist – were available within fifteen minutes, with a final refined value just over an hour afterwards. This quake, at magnitude 6.2 and with an epicentre near Eketahuna in the Wairarapa, was classified ‘severe’. It was 33 km deep – felt widely, but not so destructive as the shallow quakes that hit Christchurch in 2010-11 and Wellington in 2013. It occurred in the Pacific plate subduction zone, where the plate is being driven down by the Indo-Australian plate riding up over it. It’s no coincidence that this is right under New Zealand – the islands are a product of that collision.

Gollum in Wellington airport passenger terminal - a marvellous example of the model-maker's art.

I don’t have a photo of the Wellington airport eagles, but this is Gollum – taken last year – near the model that fell into the foodcourt. Click to enlarge.

Where I live the ‘felt intensity’ was at the high end of V on the Modified Mercalli scale. Damage around Wellington included the Weta workshop model of a Hobbit eagle  in the airport terminal, which crashed into the food-court. It was worse across the lower North Island in centres like Palmerston North. Fortunately nobody was killed or hurt.

Quakes have been on the rise in New Zealand lately. Archaeological work reveals that quakes cluster in decades-long patterns. The late twentieth century was one of the calmer periods. And now it looks as if we’re back in the action again. Christchurch, alas, may have simply been the beginning. Are they linked? Possibly. Certainly a quake in one area can increase stresses in a fault nearby that’s already under tension. But there also seems to be a general process of rising and falling activity.

The Christ Church Cathedral - icon of a city for nearly 150 years and the raison d;'etre for its founding in 1850. Now a ruin, due to be demolished.

The Christ Church Cathedral, Christchurch – photo I took in early 2013. Click to enlarge.

Best case is it will settle down. Worst case – well, there is a disturbing precedent from the fifteenth century, where a succession of massive quakes estimated at magnitude 8+ tore along the length of the country over just a few decades. One of them, circa 1460, struck just south of Wellington and filled in one of the two harbour entrances, the Te Awa-a-tia channel. Motukairangi island – modern Miramar – became a peninsula and the water within its hills swampy terrain. Peter Jackson’s studio is built on the uplifted land.

It's all in an ordinary industrial-style street.

Warehouses opposite Peter Jackson’s Park Road headquarters, Miramar – under water until 1460. Click to enlarge.

Maori named the quake Haowhenua (‘the land destroyer’). The evidence is still visible as the flat land of Miramar and the Wellington airport flats – and as beach lines at Turakirae Head. The name seemed a puzzle – a ‘land destroyer’ that produced uplift? Then archaeologists discovered evidence of 10-metre tsunamis at the same time.

The question is not ‘if’ this will happen again – but ‘when’. New Zealand has many fault lines – the largest is the Alpine Fault, which moves about every 300 years and generates quakes of magnitude 8+. We are due for one, statistically, within 50 years. Recent studies point to the existence of other large faults each side of the South Island. They are still being researched. Scary? No.  We have to accept the reality as it unfolds – and be prepared.

Do you live in an earthquake zone? If not, what natural disasters do you face?

Copyright © Matthew Wright 2014

Coming up: More writing tips, science geekery and humor. But hopefully not more quakes. For a while, anyway.

Why is the weather going mad? Humanity’s limitless stupidity, that’s why

The weather these past years seems to have gone mad, and not just in New Zealand – though here it’s been bad enough, we’ve had successions of intense storms with record-breaking wind speeds.

Wellington was in chaos for days after a ‘one in a century’ storm in June – our third in a decade – knocked out power to tens of thousands of homes, felled trees and smashed commuter infrastructure.

Two mornings after, and still raining. Photo I took of debris on Petone Beach. Storm surges drove timber from the Hutt river right up on to the road here.

My photo of debris on Petone Beach, June 2013.

The Dutch half of my family tell me that, over in the Netherlands, winter decided to give spring and summer a miss. It never warmed up until a couple of weeks before summer was due to end. Nothing seemed to stop the rain.

The Hutt river, looking south towards the rail bridge. Usually there's a lot more water in it than this.

Drought 2013, Hutt river. Usually there’s more water in it.

This week Boulder, Colorado, was awash with 1-in-1000 year floods – I picked the story up via blogs, and then news came of a couple of Kiwis living there who had to flee before the deluge. (Check out Susie Lindau’s blog, in my links. and Phil Plait’s awesome science blog ).

Meanwhile Japan – including the damaged reactor at Fukishima  – is being hammered by Typhoon Man-Yi. Half a million people have been ordered to evacuate.

I have an interest in understanding this because I’ve been writing a book on coal, environment and our attitudes (coming out next year). So is all this global storminess a coincidence? Mathematically, that’s possible. Random events – to human perception – appear to cluster. But there is a common cause. A recent analysis attributed about half the recent extreme weather to human-created climate change. Bearing in mind that ‘climate’ and ‘weather’ are not the same thing,  we’re facing the first obvious consequence of our 250 year crusade to dump fossil carbon into the atmosphere.

I’ll blog later about the science of climate change. To me, though, the way things are panning out reveals a great deal about the human condition.

My reasoning at the broadest level is this. We’ve been playing our usual trick of exploiting resources until they’re gone. That was an essential survival skill in the last Ice Age. Other species of human – the Neanderthals, the Denisovians, the ‘Hobbits’, all died. H. Sapiens alone survived – we had, it seemed, the ‘tude (it seems to have been a function of our greater ‘working memory’).

A diagram I made of where we think everybody was, mostly, using my trusty Celestia installation and some painting tools.

A diagram I made using my trusty Celestia installation and some painting tools.

It worked a treat when the human population was a few thousand. When environments were exploited, people moved on – or dwindled, as on Easter Island. But it got industrialised. World population was around a billion in 1800. Factories, locomotives, ships and households in burgeoning cities began pouring coal smoke into the air. Humanity began exploiting the environment not on a regional scale, but globally.

There was but one outcome – the biggest ‘own goal’ in the history of the world, and we’re staring down that barrel now. Into which, as far as I can tell, has swept that other component of the human condition; stupidity – intellectualised, given traction by its rational gloss. But still stupidity.

It’s evident in the way we’ve reacted to climate change. It’s been emotionalised, rationalised, politicised, reduced to catchechisms, polarised between ‘warmists’ and ‘deniers’. All for reasons that have little to do with science, and a lot to do with vested interest, political need, even personal conviction over what constitutes reality. All of it slowing efforts to understand what is happening – then take steps to fix it.

Look at it this way. Past biomass – mostly plants – built up over tens and hundreds of millions of years, has been dug up as coal, gas and oil, then burned in what, by geological standards, is an eye-blink. We’ve dumped the waste products of all those millions of years worth of ancient ecosystems into Earth’s current system in just 250 years – which, when we’re thinking on these scales – amounts to one swift hit. It’s like taking a century’s worth of household rubbish and trying to jam it into a bag that’s only good to hold the rubbish from this morning. And then we try to rationalise our way out of the consequences?

I mean – duh! What did we think was going to happen?

The people at the receiving end of unprecedented weather events are the first victims.

Copyright © Matthew Wright 2013

Coming up this weekend: “Write It Now” and “Sixty Second Writing Tips” return.

Wellington struck by more severe quakes – 16 August

As I write at 5.30 pm, my desk is rocking to three quakes in quick succession, the largest at magnitude 6.3. These are just the latest in a string that have hammered my city, Wellington in a few hectic hours this afternoon, just a month after another swarm that, we were all hoping, might be over.

Soon after the biggest – a 6.6 magnitude shock – swept over the city at 2.31 pm, the streets were filled with cars and people, getting out of town. Here’s a photo I took with my phone looking across to Parliament buildings, at the base of Molesworth street.

Pedestrians and cars at the bottom of Molesworth Street, Wellington, after the magnitude 6.6 shock of 16 August. Aftershocks up to 5+ magnitude were still rolling in when I took this.

Pedestrians and cars in unusual number at the bottom of Molesworth Street, Wellington, after the magnitude 6.6 shock of 16 August. Aftershocks up to 5+ magnitude were still rolling in when I took this.

Really, of course, we have to think of these quakes as a single large event – one with punctuated movements. What’s more, there have been other quakes around the country, likely triggered by the latest re-eruption. The ones rocking Wellington are all centred on a fault line under Cook Strait, near the South Island town of Seddon – which has taken a severe hammering.

I’d like to extend a very warm and grateful thanks to all those who got in touch with me, within a few minutes of the news spreading – and from as far away as the US – to ask how things were going. I very much appreciate your kind thoughts – thank you.

There are no injuries reported. More soon.

Copyright © Matthew Wright 2013

It’s earthquake season in New Zealand

We were jolted awake this morning in Wellington by a severe quake – magnitude 5.8. The intensity in our house was IV on the Modified Mercalli ‘felt intensity’ scale.

As I write this the national seismograph network is still picking up aftershocks – every few minutes. That followed Friday’s succession of jolts which included a 5.7 magnitude shock – felt intensity in Wellington, again, was IV. They are from a fault complex in the northern South Island, near the town of Seddon – a line stretching north towards Wellington.

Demolition under way.

My photo of demolition under way, central Christchurch, January 2013.

Quakes are a fact of life in New Zealand. It’s a part of living on the joint between two crustal plates. The other issue is volcanoes, which I covered last week. Quakes are the more immediate risk. They’ve killed more Kiwis than volcanoes. The two worst were the magnitude 7.8 Hawke’s Bay quake of February 1931, which killed 258 and seriously injured over 400; and the magnitude 6.3 quake of February 2011 that killed 185.

I had to take copyright action when this book of mine was infringed.

Cover of my book on the Hawke;’s Bay quake of 1931 – now out of print, alas.

A word of explanation . The ‘magnitude’ – what used to be the Richter scale – is a measure of energy. What counts on human level is ‘felt intensity’, a subjective measure of the energy delivered to a particular place. That varies, depending on the ground the shock wave has to travel through. In the case of the lethal Christchurch quake, bedrock reflected some of the waves back under Christchurch city, where the felt intensity was VIII – ”destructive’ to IX – ‘violent’. Peak ground accelerations were estimated at up to two gravities (19.4 m/sec/sec).

None of these came close to the quakes that shattered infant Wellington in 1848 and 1855. After the 1848 shock one settler observed that : ‘Only 1 bakers oven was left intact . . . A brick wall fell and killed Sgt. Lovell and 2 children. Medical hall kept by Dr Dorset became a scene to be imagined with bare shelves and the contents broken and badly mixed . . . A number of land slips occurred on the wooded hills between Wellington and Wairarapa and in one instance a house was shaken off the piles supporting it.

This picture of post-quake Napier isn't well known; it is from my collection and was published for the first time in the 2006 edition of my book Quake- Hawke's Bay 1931.

This picture of post-1931 quake Napier isn’t well known; it is from my collection and was published for the first time in the 2006 edition of my book ‘Quake- Hawke’s Bay 1931′. Figure facing camera is my grandfather.

Some settlers blamed poor mortar. ‘Sand and water is not very sticky,’ Charlotte Godley explained in a letter to her mother. The quake was centred on the Wairau Valley and later estimated to have a magnitude of 7.1, with a strength in Wellington of about VIII on the Modified Mercalli Scale. Wellington swayed to another tremor in May 1850.

The proverbial ‘big one’ hit in late January 1855. This was catastrophic, a major failure of the Wairarapa fault with an estimated magnitude of 8.1 or 8.2, and a peak felt intensity in Wellington of X. Destruction spread from Wellington to Wanganui, and the quake was felt as far north as Wairoa. The shelved land brought up by this quake is still visible today – in fact, roads run directly along the edge of it.

Two quakes in quick succession like that was unprecedented,

The frightening part is that some seismologists theorise they were linked. What happens, the theory goes, is that a rupture of one fault sets up tensions in adjoining rocks – setting up the next fault to break a little later.

There has been suggestion that the Christchurch quake swarm that began in September 2010 and continued into 2013 – effectively shaking the city to pieces, slo-mo style – was set up by a massive quake that hit Fijordland in 2007. As for the current quakes near Seddon…well, they’re at the other end of the Christchurch complex and…uh…the next one up are the two big Wellington faults.

Scientifically speaking, the jury’s out, but I’d hate to find out the theory’s right the hard way.

Copyright © Matthew Wright 2013

The science of the inevitable Taupo apocalypse

A couple of weeks back I read Firelands, debut dystopian thriller by US author Piper Bayard. To call the book fantastic is an understatement. I was hooked from the first pages, dropping the book I was writing myself, despite looming contract deadline, so I could keep reading.

A photo I took a few years ago. Taupo. Not a placid lake filled with trout. Well, it is. But it's also the caldera of one of the world's biggest supervolcanoes. Uh - yay.

A photo I took a few years ago. Taupo. A placid lake filled with trout. And the caldera of one of the world’s biggest supervolcanoes. Uh – yay.

Firelands is set in a post-apocalyptic future where the United States has become a theocratic dictatorship – a provocative setting that makes the novel far more than just Hunger Games for grown-ups. Firelands is in a class of its own. A wonderful, insightful, thoughtful and exciting story.

Bayard’s instrument of doom is a supervolcano – Taupo – that casts the world into darkness.  A scenario that’s not just plausible. It’s already happened at least twice.

I live within 260 km of Taupo’s Hatepe vent, so I thought I’d post about the historical apocalypse while scrabbling for my asbestos suit, hard hat and breathing apparatus.

On the face of it, Taupo is a lake with thermal district. The full name is Taupo-nui-a-Tia; ‘the great cloak of Tia’, referring to a flax cloak of the rangitira Tia. It’s often mispronounced. The first syllable rhymes with ‘tow’ as in ‘towing along’. Technically, Taupo should also have a macron over the o, indicating a long vowel. In IPA terms it’s ‘tau-poh, which is close.

Photo taken by my wife one day in early 2005 of the Orakei Korako thermal zone just north of Taupo.

Photo my wife took in early 2005 when we visited the Orakei Korako thermal zone just north of Taupo.

Pakeha (white settlers) got to know it in the 1840s. Donald McLean, the dour, God-fearing Presbyterian Scot who trudged into the district in 1846, saw a Christian apocalypse, confiding to his diary that ‘No person could see this place without feeling intensely the awful end of a miserable sinner, when committed to his last home; and may God in His providence prepare us all for such a serious change…’

The science behind that hellish setting emerged only as vulcanology developed through the twentieth century.

Turns out the lake is a caldera, part of an immense volcanic field stretching from Mount Ruapehu  to the Whakatane underwater volcano. The field has erupted many times. White Island is active now, monitored by a webcam and plastic dinosaur.

Geothermal steam from the Taupo system is used to generate power - up to 13 percent of the North Island's needs, in fact. The techniques were developed right here in New Zealand.

Geothermal steam from the Taupo system is used to generate up to 13 percent of the North Island’s power. This is my photo of the Wairakei station. The techniques were developed  in New Zealand.

All are dwarfed by Taupo itself, the centre of the system. The last eruption around 180 AD, from the Hatepe vents near the south of the lake, was modest by Taupo standards, but still cast the world into shadow.

The Oruanui eruption, Taupo, 26,500 BP. From http://en.wikipedia.org/wiki/File:Taupo_2.png

The Oruanui eruption, Taupo, 26,500 BP. Via Wikipedia.

The benchmark remains the Oruanui eruption 26,500 years ago  (earlier analysis cited 22,690 ±230 BP), to the north of the current lake and the world’s last eruption to score 8 on the Volcanic Explosivity Index – the maximum. Back then, the lake was different, known to paleogeographers as Lake Huka. In 2012, PhD student Aidan Allen discovered the trigger for this cataclysm was likely an earthquake.

The eruption blew out the current lake bed – and more. Everything in the central North Island was destroyed by a fall of ingimbrite some 200 metres deep. Then there were devastating floods. Even the major river, the Waikato, changed its course. Ash fell  as far away as the Chathams.

It was a world cataclysm. Although debate continues over specific triggers for Pleistocene glacial cycles, there is evidence that the worldwide glacial maximum that began 26,500 years ago was pushed, in part, by this eruption. In New Zealand, certainly, a warming period prior to the eruption came to a dead stop afterwards.

Oruanui may not have caused the glacial cycle alone – but  it made things worse. Humanity was nearly wiped out in the deep cold that followed. The downturn seems to have been the last blow for Neanderthals, our cousin species already reduced to the edge of extinction at Gibraltar. It destroyed a nascent H. Sapiens agricultural revolution among the Gravettian culture in what are now Russian steppelands. Had that not been cut short, civilisation might have been with us 20,000 years earlier.

This was the apocalypse, Pleistocene style.

And to give that perspective, the Oruanui blast was itself dwarfed by the Whakamaru eruption in the same zone, 254,000 years ago.

We’ll have warning before the next one. Taupo is monitored by New Zealand’s Geological and Nuclear Sciences department via GPS and seismographic stations. No rubber dinosaur, but hey…

Hopefully it won’t happen in our lifetimes. Because when it does, it will bring the apocalypse. Certainly for New Zealand, maybe the world.

Copyright © Matthew Wright 2013