Friday, July 07, 2017

Autobiographical reminiscence: the phases of Venus

As a child, I loved stargazing, and this was a pretty easy thing to do growing up on a farm. We had constellation charts that were stored in the bottom shelf of the glass-fronted bookcase in the sitting room, and I learned to locate and name them. I think the charts may have come from Weekly Times special offers, which was how we acquired a Readers Digest atlas. (The Weekly Times was a newspaper devoted to rural issues).

The constellation of Andromeda
Of course the names were often figures from Greek and Roman mythology: Orion, Andromeda, Gemini, Perseus, etc. Among the books in the glass-fronted bookcase were volumes of classical mythology retold for popular consumption, which I devoured; and it only now occurs to me that the constellations united the stars and ancient civilisations in my mind. Perhaps it was not so illogical to love both astronomy and archaeology.

Venus was always my favourite planet. Not only was it the brightest thing in the firmament after the Moon, but Aphrodite seemed like a much more interesting goddess than any of the others - even Athene. I might have been a bookworm, but I wasn't giving up the allure of the flesh on that account. And of course, Venus is the only female planet to identify with.

My friend Ged remembers me pointing out Venus in the dawn sky when I was staying over on her parent's property, in primary school days. Something puzzled me, though. I had read of how the ancient Babylonian astronomers charted the phases of Venus (this may have been in one of my archaeology kid's books, or an encyclopedia). For the life of me, I couldn't see how this could be done. They didn't have telescopes, and I couldn't see any bloody phases. I never asked anyone about this; well, country NSW wasn't exactly crawling with astronomers, and there was no internet then.

In 6th grade, at the age of 10, it came to my mother's attention that I was short-sighted, and probably had been the whole time. I'd just developed strategies to make up for the fact that I couldn't read the blackboard at school, and it never occurred to me that everyone didn't experience the world like this. So I was duly taken away to get glasses. Suddenly, my father's hitherto mysterious ability to identify the species of a flying bird was revealed. I had thought him terribly clever because he clearly could distinguish between flying styles. Now I realised he could actually see them.

Ah, I thought. So this was how the Babylonian astronomers did it. They could see the phases of Venus without the benefit of modern telescopes.

It was now much easier to tell the difference between the stars and planets as the telltale twinkling was more obvious, and I could at last see the rabbit on the Moon.

However, this new sight was both a blessing and a curse. Glasses cemented a certain reputation captured by Dorothy Parker's famous aphorism: Men seldom make passes at girls who wear glasses. Being seen as smart was antithetical to being seen as desirable, the pinnacle of a woman's achievement. Athene was taking ascendency over Aphrodite as the contradictions and constraints of being a teenage girl were ushered in with high school life.

Another phase of Venus was about to begin.




Saturday, June 24, 2017

'Ah, that was a beautiful piece of engineering and archaeology!'. Cordwainer Smith's IOM rocket.

I'm always fascinated by how science fiction writers portray archaeology.  A couple of weeks ago, I was wandering through the Adelaide Central Markets on my way to work, and I spied a second-hand book sale. There was a box of old science fiction, and one leapt out at me: Cordwainer Smith's Space Lords, which I did not have.

To my delight, this volume of short stories contained one that I'd never read either. Drunkboat is the story of how the Lord Crudelta precipitated the discovery of Space3. I knew of the story as some critics have discussed it in reference to the evolution of the Vomact family. 

Leaving the plot aside, here is how Cordwainer Smith imagines a kind of space archaeology:
We had put him in a rocket of the most ancient style. We also wrote writing on the outside of it, just the way the Ancients did when they first ventured into space. Ah, that was a beautiful piece of engineering and archeology! We copied everything right down to the correct models of fifteen thousand years ago, when the Paroskii and Murkins were racing each other into space. The rocket was white, with a red and white gantry beside it. The letters IOM were on the rocket, not that the words mattered.

IOM, of course, stands for the Instrumentality of Mankind. The national symbols that adorned spacecraft in the 20th and 21st centuries are mystifying to the denizens of the future, but they copy them anyway.

Fifteen thousand years on from the Cold War space race - I assume the Paroskii and the Murkins are meant to represent the USSR and the USA - there's sufficient documentation and models of the early rockets to replicate them. The IOM rocket is thus a facsimile of old technology. If we think about what was happening 15 000 years ago for us, one of the principle technologies was the manufacture of stone tools. So perhaps this was like something archaeologists might do today in replicating a Magdalenian retouched point.

Magdalenian flaked stone artefacts, from Debout et al 2012
http://www.sciencedirect.com/science/article/pii/S1040618212003436
Such technology is often called 'primitive' in popular accounts, but it was very far from that, requiring a highly sophisticated knowledge of geology and engineering too - understanding the mechanical, chemical and fracture properties of stone are essential to making stone tools. Learning how to actually make and use ancient technologies is sometimes called ethnoarchaeology, and the idea is that you can learn something about how people lived in the past that simply analysing the artefact as an object cannot reveal.

Similarly, the facsimile of the rocket demands both engineering and archaeology to make it more than just another model. The rocket is launched from its red and white gantry - cheerful picnic colours - and if you want to know the rest, you will have to read the story.




Saturday, June 03, 2017

Cable ties in literature: from the boudoir to the post-apocalyptic

It's no secret that I have an obsession with cable ties. The nice thing is that when I explain their fascinating history to people, they often catch the bug as well, coming to appreciate the stunningly simple design of this monumentally successful piece of technology. If you want to know the full story, you can read my paper on cable ties here.

Anastasia Steel and Christian Grey in the cable tie section of the
hardware store. I mean seriously. What a depauperate population
of the popular plastic fastening device.
Sadly, cable ties have not yet set the world of literature alight, unless you count their famous appearance in Fifty Shades of Grey. I would say that E.L James paid insufficient attention to cable ties as critical material infrastructure in her novel; and the range of cable ties available in the hardware shop in the film version is frankly disappointing.






Hugh Howey's Wool is a different proposition. I was lent this book by a friend and was astonished that I hadn't heard of it before. It was immediately enthralling, and there really is nothing nicer than finding a new author whose work just makes you want to read more.

So you can perhaps imagine my breathless excitement when I started Chapter 21 of Wool to find a description of CABLE TIES OF THE FUTURE.

Oh yes.

So here, for your delectation, is the passage in question. I don't think there are any spoilers in it if you haven't read the book.

The next morning Juliette arrived early at her desk having stolen little more than four hours of sleep. Beside her computer, she saw a package waiting for her: a small bundle wrapped in recycled pulp paper and encircled with white electrical ties. She smiled at this last touch and reached into her overalls for her multi-tool. Pulling out the smallest pick from the tool, she stuck it into the clasp of one of the electrical ties and slowly pulled the ratcheting device apart, keeping it intact for future use. She remembered the trouble she'd gotten into as a mechanic's shadow the day she'd been caught cutting a plastic tie from an electrical board. Walker, already an old crank those decades ago, had yelled at her for the waste and then shown her how to tease the little clasp loose to preserve the tie for later use. 
Years had passed, and when she was much older, she had found herself passing this lesson on to another shadow named Scottie. He had been a young lad at the time, but she had had a go at him when he had made the same careless mistake she once had. ... 
She loosened the other tie crossing the package and knew the bundle was from him. Several years ago, Scottie had been recruited by IT and had moved up to the thirties. He had become 'too smart for Mechanical', as Knox had put it. Juliette set the two electrical straps aside and pictured the young man preparing this package for her. The request she'd wired down to Mechanical the night before must've bounced back up to him, and he had spent the night dutifully doing her this favour. 
She pried the paper apart carefully. Both it and the plastic ties would need to be returned; they were both too dear for her to keep and light enough to porter on the cheap. As the package came apart, she noticed that Scottie had crimped the edges and had folded these tabs under each other, a trick children learned so they could wrap notes without the expense of glue or tape.

Scottie leaves her a note: Keep the ties - I got plenty. 

Where do I start? There is so much going on here, and although I believe there are some technical unlikelihoods, on the whole Howey has paid the cable tie much greater respect as an artefact than E.L James.

At this point I must digress. I searched for a link to Wool to include and discovered something that astonished me. Another reviewer HAS ALREADY COMPARED WOOL TO FIFTY SHADES OF GREY.

What.

Science fiction's answer to Fifty Shades of Grey, the review in the Guardian says. Perhaps I missed the BDSM scenes in Wool. I'm pretty sure I did. And I may be wrong, but I'm also pretty sure that few reviewers take the cable tie approach to literature. Well there's nothing for it but to read this other review.

Ah, now I read that the comparison is made on the basis that both works were initially self-published. There is no mention of cable ties. So I shall continue.

Juliette's cable ties are described as "white electrical". This is the industrial context in which cable ties were first invented, when Maurus C. Logan visited the Boeing factory in 1956 and watched the workers tying up the electrical wiring in an aircraft. He was employed by US electrical outfitters Thomas and Betts. Since their first manufacture, cable ties migrated into everyday life and a myriad of uses securing every kind of thing. Here, in the isolated culture of the silo, sealed off against the toxic world outside, cable ties have retreated to their original use.



Colour is significant in cable tie manufacture. Black cable ties are generally intended for outdoor use; their carbon content makes them UV resistant. In the silo, the cable ties are white. They will never be used outside, as no-one can survive outside in the poisoned atmosphere. They're like little pale fishes trapped in an underground pool.

There are two types of cable ties, those which have to be cut off and can't be re-used, and re-usable ones, which need to be undone with a special tool. It's not entirely clear from Howey's account which is intended here. If you loosen the ratchet head, will it really be useable again as it won't engage with the ridged tail? Juliette doesn't seem to be using a specialised tool, just the smallest one from her panoply.

This is a minor point against the real implications of the passage however: that in the closed world of the silo, an artefact that was once mass-produced and discarded without thought is now precious and valuable.

The cable ties are symbolic here as well: Scottie is using them as a material allusion to the history that he and Juliette share, knowing that they will make her recall the past. They symbolise the passing on of knowledge: the creation of new bonds - as well as their dissolution. They are used to secure the parcel, but they are part of the gift as well.

Fastening is an art when materials to secure objects are in short supply. The parcel is a contradiction of meanings. Scottie has used the valuable cable ties to hold it all together, but in the first layer he has employed the technique learned from childhood to fold the paper together. Here we see a discipline of alternatives in an alternative world.

I particularly appreciate the thought that has gone into this passage, projecting a social and technological context for an artefact of the present into the future. It's what science fiction does best.

So my Cable Ties in Literature Award today goes to Hugh Howey for Wool. It is perhaps not quite on the level of other literary awards, given the small pool of nominees. Nevertheless, I regard it as an achievement. Congratulations, Hugh.





Thursday, May 11, 2017

How geodesy created a vision of the Earth through the jewelled LAGEOS satellites

Image courtesy of NASA
Could this be the most beautiful satellite ever made? In fact it is one of twins, as there are two of these jewelled spheres in Earth orbit. They're the LAGEOS satellites, essentially inert reflectors to bounce lasers off. The jewels are fused silica, except for four made from germanium. The interior is not a void filled with instruments: it's a solid brass cylindrical core, covered in a thick aluminium shell, as you can see in the video below.

(Hang on, you say. Fused silica? Isn't that just glass? Well yes and no. It's amorphous silica, but without any of the other ingredients that make up the glass we use, like lime, soda and potash).

LAGEOS stands for  LAser GEOdynamic Satellite. The first was launched by the US on May 4 1976, and the second, made by the Italian Space Agency, was launched in 1992.  This means in 2017 the 60 cm sphere - harking back to the spherical satellites of the early space age, such as Sputnik, Vanguard and Echo, achieved 41 years in orbit. It's a veteran of space science.

And because they're completely passive, with no power, fuel, solar panels or instruments, their missions are not ending any time soon. They should be up there for about 8.4 million years according to the original prediction! They can just keep going until their reflectors are too weathered by exposure to the space environment to bounce a laser back to Earth. The glass eyes are meant to be dust and radiation-resistant, but, just like the famous space shuttle windows, they could be damaged by hypervelocity particle impact. Perhaps the quality of the return signal could even be a way of measuring deterioration in the surfaces since launch, and hence gauging something about taphonomy in space. I wonder if this is possible?


The two satellites orbit at around 6000 km in a circular polar orbit. The information they have provided has contributed to new perspectives of the Earth, as former LAGEOS project scientist David E. Smith explains
Today, we see Earth as one system, with the planet’s shape, rotation, atmosphere, gravitational field and the motions of the continents all connected. We take it for granted now, but LAGEOS helped us arrive at that view.
Even more importantly, the two LAGEOS define the centre point, based on the Earth's centre of mass, for the terrestrial reference system used in navigation.

One of the things they're used for is to measure the speed and direction of tectonic plate movement. Because of this, LAGEOS-1 was the recipient of one of Carl Sagan's time-travel interspecies communications.  He conceived a design - drawn by Jon Lomberg who also worked with him on the Voyager Golden Records - engraved on a thin steel plate that was wrapped around the brass cylinder core - depicting continental drift at three points in time: 268 million years ago, 1976, and in 8.4 million years. You'd have to crack the satellite open like an egg, though, to get at the message. It's precisely the sort of alien mystery object that science fiction writers imagine falling to a planet and catalysing personal and social revelations, even when the object is impenetrable. Who knows who or what might find it in 8.4 million years? Will it melt in re-entry, fall into the ocean unnoticed and unmourned, or slam into the Australian outback like Skylab, to lie under the stars for another few million years?

There's another little mystery too. LAGEOS 1 has the most precisely know orbit of any orbital object. In 1978, LAGEOS-1 began descending at a much greater rate than it should have. In 1983, as David E. Smith described in a Nature paper, the satellite rather unexpectedly began to ascend again. It's still losing altitude - 1.33 mm each day - but because it is mostly beyond the reach of the atmosphere which drags objects in lower orbits back in, the cause of the decay is still a matter of debate.

And here's another interesting fact. The Optus B series of GEO telecommunications satellites have laser retroreflectors mounted on them too. My colleague Owen Mace (one of the pioneering Australis Oscar V team) had the contract to make them. Optus B1 is in the GEO graveyard orbit; Optus B2 exploded on launch, and Optus B3 was replaced by Optus D1. This means it is still in GEO but technically classified as space junk. Is anyone ranging to the two reflectors? I don't know....


References
Dey, Uijal, Kar, Samanwita, and Amitabha Ghosh 2016 Possible effect of the Earth's intertial induction on the orbital decay of LAGEOS. Journal of Astrophysics and Astronomy 37(3):1-9

Fitzmaurice, M.W., Minott, P.O., Abshire, J.B. and H. E. Rowe 1977 Prelaunch testing of the Laser Geodynamic Satellite (LAGEOS). NASA report

Smith, David E. 1983 Acceleration on LAGEOS spacecraft.  Nature Vol 304 p 15


Note: after I began writing this blog post, it morphed into an article for The Conversation.



Sunday, April 02, 2017

Barometers, dip compasses, pressed flowers, dead birds: Alexander von Humboldt and multidisciplinarity

The name Alexander von Humboldt (1769-1859) first crossed my eyes as a pre-teen, when, after pestering my mother for something good to read, she gave me The Kon Tiki Expedition. I was instantly hooked and read it over and over again as a teenager. Thor Heyerdahl's daring 1947 expedition to South America on a balsa wood raft relied on the Humboldt Current to carry them part of the way. Thus I learned of the existence of this legendary scientist and humanist.

There seems to be a lot of Humboldt around at the moment, and I'm currently reading a round table critique of a 2009 book about him, The Passage to Cosmos, by Laura Dassow Walls.  

Humboldt had what seems to be a rather modern view of the planet Earth, which prefigured the vision of the International Geophysical Year. He saw grand global processes and the connectedness which created a unitary Earth; this was reflected in his final (unfinished) five volume work entitled simply Cosmos.

He was so famous in his time that the state of US state of Nevada was almost named after him! This is how round table contributor Felipe Fernández-Armesto describes him:
He had started his scientific career like an encyclopaedist of the Middle Ages, gathering the learning of the world. He became the last magus of the Renaissance, attempting the blasphemy of comprehending the cosmos.
Michael F. Robinson notes his collecting obsessions: Barometers, dip compasses, pressed flowers, dead birds: they fill the Baron’s world. This is the kind of list which appeals to my archaeologist's heart through the contrast of artefacts hard, soft, dead, half-alive and never alive: equal weight given to the cold scientific instrument and the petals of an ephemeral flower.

Part of what resonates in this round table is the discussion of how Humboldt defied divisions between science and humanities, which were not as hard and fast then as they are now. I have been pondering this lately because, as a space archaeologist, I make it my business to read the relevant literature in the space science and engineering journals. I need to in order to pursue my research; it's as simple as that.

I notice, however, that this is often a one-way flow. Numerous of my colleagues in the space world will happily write and publish on themes of history, social sciences and environmental sciences without referring to the research carried out by scholars in those fields. Hence a lot of it reads as rather naive with undergraduate assumptions about human behaviour and the nature of scientific enquiry. They get away with it because their peer reviewers are equally unaware of scholarship outside their own fields. So it's nice to contemplate a great thinker who would have had none of these silos - even if he inadvertently helped create them.

Walls argues that Humboldt invented 
a way of speaking, about nature that we now call ‘environmental’: namely, a planetary interactive causal network operating across multiple scale levels, temporal and spatial, individual to social to natural, scientific to aesthetic to spiritual (2009:11).
Human impacts - clearing vegetation, altering water flows through irrigation - were also part of Humboldt's conceptualisation of the world: very Anthropocene, we would now say. 

The message of Walls' book is that the divisions between science and the humanities no longer serve the world well. As someone trying to bridge these divisions myself, I cannot but agree.


Reference
H-Environment Roundtable Reviews Volume 2 No. 4 (2012) www.h-net.org/~environ/roundtables Laura Dassow Walls, The Passage to Cosmos: Alexander von Humboldt and the Shaping of America (Chicago: University of Chicago Press, 2009). 


Sunday, February 12, 2017

Surveyor 3 - the only multi-occupation site on the Moon

I've been looking at the amazing pictures of astronaut Alan Bean visiting the Surveyor 3 robotic lunar landing craft to remove a camera for return to Earth, in 1969. Something so obvious suddenly struck me and I wondered why I had not seen it before.

Surveyor 3 was part of a series of landing missions that left seven craft on the surface of the Moon. In November 1969, Apollo 12 landed on the edge of a crater, just 180 m from Surveyor 3, launched two years before. The two astronauts, Pete Conrad and Alan Bean, walked over the Surveyor 3 and removed a camera and a couple of other pieces for analysis. (This analysis showed evidence of 'scouring' on the Surveyor surfaces, a result of dust stirred up by the Apollo 12 landing).

Image courtesy of NASA
All of the Apollo sites are of a particular type: there's a landing module, numerous places where samples were taken, cameras and flags set up, the "toss zone" of discarded objects, the odd rover, and countless astronaut bootprints. 

Surveyor 3 is the only lunar site with astronaut footprints that was not a human landing mission. So you have an interesting mismatch of archaeological traces - a spacecraft which is not capable of containing human bodies, nor of moving, yet surrounded with the evidence of human movement.

You could argue that Surveyor 3 and Apollo are now part of the same site as they preserve evidence of interaction between the two locations. They're close in both time and space.

It's like a rockshelter with archaeological deposit, with only sparse evidence of occupation - some stone tools and a hearth -  at 18 000 years before present (bp), followed 10 000 years later by a denser layer of stone tools, bones, and hearths. Imagine this time frame telescoped with the acceleration of modern technology and spread flat across the landscape instead of stratified.

In archaeology, it's not unusual to find evidence of people incorporating artefact and places from the past into their lives. Stone tools from older campsites are re-used and sharpened, sometimes thousands of years later; masonry is scavenged from old buildings to be incorporated into newer ones. This is a practice known as spolia

This isn't exactly re-use; it's more in the nature of a scientific sample. Still, it illustrates something about how artefacts often move between space and Earth and end up out of context.

So, unlike all other lunar landing sites at the present time, the Surveyor 3 site is the only one which is the result of multiple visits. It's a rare human-robot encounter on a far world, receding further into the past with each passing year.

And incidentally, 2017 is Surveyor 3's 50th anniversary. 




Friday, January 27, 2017

Technological rites of passage in the liminal space of Earth orbit.

In February 2016, a  cosmonaut on the International Space Station lobbed a USB stick out of the hatch to become an orbital object for perhaps a few weeks, before a fiery death in the Earth's atmosphere. To give it enough mass to leave, it was attached to an empty film cannister stuffed with paper towels. Presumably these objects were due for disposal as waste in any case.

Cosmonaut Sergey Volkov about to release the package.
Image credit: NASA TV
The USB stick contained messages and videos from the 2015 celebration of Victory Day, May 9, which commemorates German surrender to the USSR at the end of World War II. It was the 70th anniversary of this day.

It's not entirely clear from the media accounts whether the flash drive was material from the cosmonauts themselves, or of Russian people and celebrations back on Earth. I think it is most likely the latter, as otherwise, surely, cosmonauts could have thrown their own USB out for the actual 70th anniversary in 2015, rather than a year later in 2016.  (Although I suppose they may have had to wait for an EVA).

It's worth musing a little further on this hybrid orbital object, though. It was composed partly of junk, and yet it was not itself junk. The usual definition of space junk is something in orbit that does not serve a useful purpose now or in the foreseeable future. Mostly, we think of space junk as all the many thousands of defunct satellites, rocket bodies and fragments of spacecraft.

The purpose of this object was (1) to BE in orbit and (2) to vanish from orbit. Its brief passage of time in space between launch and de-orbit was all it was about. Clearly, though, the materiality and physicality of both the object and the sequence of events is important - the fact that it happened even though no evidence survives and no-one can access those messages and images.

It's hybrid nature is also evident in the combination of tangible objects and intangible data. The videos and messages were not actually playing as they left the ISS. They were passive and silent. You'd have to plug the USB stick into a computer to see what they were. In this ceremonial act, seeing the videos and listening to the messages was not important.

You could argue that the data was not intangible as it was physically stored in the device as 0s and 1s. What's intangible, though, is the interpretation and meaning given to a certain de-coding of those numbers, as perceived by a body with a certain range of senses.

The old archaeology joke is that if you can't tell what the hell an artefact was used for, then it was ceremonial or ritual. Sometimes this is actually true! Rituals can be classified in a number of ways. The celebration of Victory Day is a commemorative rite, marking the end of a war. On Earth there are probably millions of war memorials from grand triumphal monuments to plaques and honour boards. They have a static component and an active component when people gather on significant days to carry out ritual actions and speak ritual words. The USB release is also commemorative as it marks the 70th anniversary of a ritual.

But it's also a sort of technological rite of passage. Van Gennep's classic Les Rites de Passage uses the metaphor of passing from one room of the house to the next. The nature of the commemoration was to allow the USB to pass from one state, space, to another, the Earth. In van Gennep' terms, the stages of the ritual are separation, liminality and incorporation. Orbit becomes the liminal space, neither one state nor the other, suspended, falling, as ambiguous as the junk-notjunk. Incorporation comes when the object disintegrates in the atmosphere, returning to Earth with the new identity of spaceflown object. For this ritual, to have lived and died in space is more important than never having existed in the first place.


Note: I wrote about this because I found some notes scribbled on a piece of paper from a talk preparation, so this is to help me remember the ideas - I've recycled the paper already!