Category Archives: Science fiction

Far from the Spaceports, Science, Science fiction, The Liminal Zone, Timing

Dawn, death, and ion drives

November 7, 2018 RichardAbbott Leave a comment

Dawn takes off, September 27th 2007 (KSC/NASA)

Last week, NASA’s Dawn space probe, which first launched back in 2007, finally ran out of fuel and has been declared dead. Regular readers will know that Dawn has been a great source of information and inspiration for me as I have been creating the future world of Far from the Spaceports, Timing, and the in-progress The Liminal Zone. So it seemed fitting to me to do a kind of tribute to Dawn here.

So here’s a timeline of key events:

September 2007 — Launch
February 2009 — Mars Gravity Assist
July 2011 — Vesta Arrival
September 2012 — Vesta Departure
March 2015 — Ceres Arrival
June 2016 — End of prime mission
July 2016 — Start of first extension
November 2017 — Start of second extension
November 2018 — No remaining fuel: mission ends

Enhanced colour image of Ceres (NASA/JPL-Caltech/UCLA/MPS/DLR/IDA)

Of course, Dawn is not going anywhere – it will remain in its current orbit around Ceres for decades at least, until some combination of inevitable gravitational perturbations distorts that orbit enough that it eventually crashes into the surface. But there will be no more navigation from Dawn, no more course correction, no more photos or science information.

I want to talk a bit about Dawn’s ion drive, in the connection of storytelling, but if you want pictures and information about the mission findings, the best place to start is the NASA site, which has separate pages for Vesta and Ceres.

So, the ion drive. Most craft up to now have used chemical rockets – two or more chemicals are stored separately, then mixed to form a high-energy burst of propulsion. For example, the latest SpaceX SuperDraco engine uses the two liquids nitrogen tetroxide and Monomethylhydrazine. The net effect is that the spacecraft is pushed with high acceleration in a particular direction. After this engine burn, the craft coasts with no further propulsion for days or months, until it’s time for another correction. Astronauts in the craft have to endure short periods of high g-forces, followed by long periods of weightlessness. The engine burns have to be very precisely calculated for direction, force, and duration, so as to minimise the need for subsequent burns. Once the fuel is gone, it’s gone, and each burn takes a fair proportion of the fuel stores.

What does this mean for storytelling? Well, most of the journey is spent at zero acceleration, coasting towards your destination without burning fuel, and without any sense of up or down. It took the Apollo astronauts about three days to get from the Earth to the Moon (and the same back again, after doing stuff on the lunar surface). As and when SpaceX or whoever sends another rocket there, it will still take about three days – the time taken is a result of the coasting period without power, not the force of the engine. And because of the long zero-gravity sections, you need to be fairly well-trained to manage this.

SpaceX 'Starman' orbit (SpaceX Twitter feed) — SpaceX ‘Starman’ orbit (SpaceX Twitter feed)

Now consider a trip to Mars. In February of this year, SpaceX launched a Falcon Heavy rocket, with payload of a Tesla car and suitable contents. It left Earth orbit and headed out on an orbit that goes out past Mars, but at a slight angle so that the two never intersect. Each orbit takes 557 days to complete, so at this point not even one has been finished. The payload – a Tesla car – passed by Mars orbit a few days ago, after about eight months.

The Hermes rocket from the film The Martian (http://the-martian.wikia.com)

Now, this rocket had not reserved enough fuel to slow down and enter Mars orbit – it was a vivid proof of concept for SpaceX, not a real attempt to land on the Red Planet. But basically, if a human crew does the same journey in the same rocket, it will take them about eight months to get there – eight months of zero gravity, unless rocket design changes to include a kind of pseudo-gravity produced by rotation, as in the Hermes spacecraft in The Martian.

Getting out into the solar system on chemical rockets just prolongs these figures. Potential astronauts have to cope with months, if not years, of isolation and low gravity. It is just not viable to send people there, which is why the present focus has been on sending hardware and instruments.

Schematic diagram of ion drive (NASA/JPL)

Enter the ion drive, as used on Dawn and a handful of other craft. It is, in some ways, the opposite of a chemical rocket. It produces small amounts of drive thrust continuously for a very long time. NASA estimates that the thrust of the engines on Dawn is roughly the same as what you feel when you hold a piece of paper on the palm of your hand. It’s quite useless for getting off the Earth’s surface – you really do need something powerful for that – but as a way to get you from Earth to Vesta… or Vesta to Ceres… From a standing start in free space, Dawn would take about four days to go from 0 to 60 mph. But that ion drive just keeps piling on speed. Dawn’s engine ran for a total of about 2000 days during the mission – over 5 years.

Artist's impression, Dawn at Ceres (NASA/JPL) — Artist’s impression, Dawn at Ceres (NASA/JPL)

Now, if you have an engine that is always-on, your whole picture of the solar system changes. Let’s suppose you keep accelerating to the mid point, then flip over and decelerate the rest of the way, so that you get to feel a constant gravity all the way. Then further is more efficient. In twice the time you can go four times the distance. Or, to put the same thing another way, to go twice the distance takes less than one and a half times the time.

Of course, Dawn’s motors were still early versions of the design, with a low thrust output even at maximum. For my stories, I’ve assumed that the design can be enhanced to give an acceleration equivalent to 1/20 of that at Earth’s surface – considerably less than what you get on the moon. It would take some getting used to, but it means that your body and brain have a clear sense of up and down, and all those physiological functions that need gravity have a good chance to keep going! What does this mean for travel time?

Earth to Mars takes between ten and twenty days, depending on their relative position at the time of launch
Earth to Ceres takes about 3 weeks
Earth to Pluto takes about three months

That works for storytelling – it’s not very different from journeys that people would take by sail back in the day. For example, an 18th century trip from England to India would take something like four to six months. Once the Suez canal was open, this reduced to about two months. People will put up with a journey like that for all kinds of reasons. So that’s roughly how you can imagine the solar system of my science fiction novels – a bit like our world was in the days of sail and early steam ships.

Here’s a short extract from Timing, in which journey time gets discussed a bit. Meanwhile, RIP Dawn!

Then, quite suddenly, I had been sent all the way to the Jovian system. That would have been fair enough after the local jobs, but it turned out to be a false alarm. One of the analysts thought he had seen a recurrence of an old scam, running out of the Callisto hub. So off we had gone – a long journey for both Slate and I, and when we left Earth orbit the planetary alignment meant there were no friendly stopovers to break the journey.

Once we got there, the two of us had poked around, wormed our way into this module and that, but found nothing. To be sure, we confirmed that the reported irregularities were real. We had easily managed to find the batch runs where the credit had gone missing, by comparing input and output. It happened every time a specific input value was missing or unreadable, and a default value had to be assumed. But the chosen default looked right and we couldn’t find root cause. The code was non-standard, and frustratingly weird, but there was nothing obviously suspicious. The logs were so skimpy as to be almost useless. It did not seem to be the kind of task that needed our skills, nor to be as much of a problem as the analyst had first thought.

When it was over, and having drawn a blank, we sent a summary report down to the Finsbury Circus office, suggesting that perhaps it would be more effective to send an accountant. We had managed to get four weeks out of the work, but it still felt like a long drag for not much return. To be fair, it was unusual for the analysts to make a mistake like that, so I was professionally polite rather than curt. Then it was time to warm up the engines of our sloop, the Harbour Porpoise, and off we set on the homeward leg.

I was all set for a boring journey back down the gravity hill to Earth, but Slate found an orbital option which would take us right past the Scilly Isles. That settled it. We deserved a reward for our fruitless diligence. So we changed the navigation plan, sent some messages ahead, and here we were. Elias, my manager back in London, had made a token protest at the diversion, but I told him that the Harbour Porpoise needed servicing and the delay was unavoidable.

Anyway, a couple of hours signal lag meant that we were already en route by the time his answer came back. We just said that we didn’t have enough reaction mass for such a radical course change. It might even have been true, though I was careful not to ask Slate for a technical analysis, and she was just as careful not to offer one.

Regardless of that, we weren’t minded to listen. Slate and I both reckoned that we deserved the break. Six weeks of voyage out to Callisto, and four weeks of fairly dull work had not made us receptive to a tedious trip straight back home again. It would mean nearly three months’ travel time for just one month of work, and we weren’t about to just put up with that without an argument.

Book promotion, Extract, Far from the Spaceports, Science, Science fiction, The Liminal Zone, Timing

Ultima Thule

October 30, 2018 RichardAbbott Leave a comment

Today’s blog is focused on the next target of the New Horizons probe, which back in July 2015 sent back such remarkable pictures of Pluto and Charon. But before that, here’s a quick reminder of this week’s Kindle Countdown deals for Far from the Spaceports and Timing – £0.99 / $0.99 for the next couple of days. Follow these links…

Right. New Horizons. After the Pluto flyby, the natural question was, what next? There was enough fuel and energy reserves to consider a small course change… but to what end? Pluto is at the inside edge of the Kuiper Belt, a tenuous and very sparsely populated volume of space. Over the last few years, we have been steadily gaining information about some of the contents, many of which have hugely elongated orbits. The big prize out there is the possibility of a really sizeable planet, acting as a gravitational shepherd to coax the smaller bodies into resonant patterns.

Planet 9 has not yet been found, but several smaller bodies have. And one of them, catalogue number KBO 2014 MU69 , happened to be well placed for New Horizons. So, an appropriate course change was made as Pluto dwindled into the distance, and KBO 2014 MU69 – now provisionally renamed Ultima Thule – became the next goal.

Current New Horizons view of Ultima Thule (NASA/JHUAPL/SwRI) — Current New Horizons view of Ultima Thule (small dot on right-hand frame) (NASA/JHUAPL/SwRI)

But distances out in the Kuiper Belt are large, so there has been a considerable wait. Ultima Thule is about 12% further away from Earth as Pluto is. The actual flyby will occur on January 1st next year, and at this stage we still don’t really know what to expect. The Hubble telescope orbiting Earth shows Ultima Thule as just a slowly moving point of light. New Horizons is about 33 million miles away from it – about 1/3 the Earth-Sun distance – and still can’t resolve it to more than just a point source. We cannot make out any surface detail. We don’t know if it’s roughly spherical, or irregular, or even a little cluster of fragments all moving together. Just about all we know is that it’s less than 40 km across, and although very dark by the standards we are used to in the inner system, is slightly more reflective than expected.

Artist's impression, New Horizons and Ultima Thule (Steve Gribben/NASA/JHUAPL/SwRI) — Artist’s impression, New Horizons and Ultima Thule (Steve Gribben/NASA/JHUAPL/SwRI)

After sending the Pluto and Charon data home, New Horizons went to sleep for a couple of years, with a wake-up call in June for some of the instruments and a course correction. It is now being prepared as best we can for the encounter. It’s a fascinating problem – light or radio signals take around 6 hours to cross the gulf between us and the probe, so there is no possibility of direct control. Any reply takes another 6 hours to get back. The systems have to be set up in advance, according to our best guess of what will be there. The final course changes will occur in mid December, when the ground crew wil decide just how close to steer towards Ultima Thule. In one sense, the nearer the better… but the higher the risk that the probe will make brief, catastrophic contact with some fragment of rock and ice. On the day, the probe will whistle by at over 30000 km/h, so there’s no opportunity for second chances. Whatever sequence has been set up in advance, will be played out without modifications. After that, New Horizons will spend the better part of two years streaming the data back to Earth. So although the rendezvous will be a New Year treat, we shall have to wait a long time until we get any high-resolution images or other data.

As yet I haven’t written about what life might be like in a suitably protected environment out in the Kuiper Belt… maybe this encounter will be the seed of another book, in the way that the flyby past Pluto and Charon has contributed to The Liminal Zone. And here, just for a bit of fun, are someone’s first impressions of the settlement on Charon, extracted from the early sections of The Liminal Zone…

Nina walked steadily along the winding curves of Lethe towards Asphodel. The house AI had finally told her where Lance’s quarters were situated in Acheron, and had transferred directions onto a hand-held to direct her there. From space, the overall shape of the Charon settlement had been clear – five sinuous linear habitats, following curves in the underlying terrain and joined radially to Asphodel. When you were actually down here, it wasn’t nearly so neatly divided. There were extra little corridors and alcoves which broke up the superficial symmetry, and little tunnels that dived underground and then resurfaced at unexpected places. She was glad that the little hand-held router buzzed faintly at junctions to tell her which way to turn.

Book promotion, Extract, Far from the Spaceports, Science fiction, Timing

Changes… and Kindle Countdown deals

October 26, 2018 RichardAbbott Leave a comment

A short post this week, mainly consisting of two extracts, one each from Far from the Spaceports and Timing. These are both on Kindle Countdown deals from this Friday, October 26th, for one week, price set at £0.99 / $0.99 depending which side of the Atlantic you’re on. More of that later… here are the extracts.

The main characters are Mitnash (Mit) and his AI persona partner Slate. in this extract, Mit and Slate are recovering from a difficult episode in which Slate was hacked by a shady individual known as The Wise Man…

Far from the Spaceports (follow this link)

Far from the Spaceports cover

“Slate, how much do I talk to you without knowing it?”
She was amused.
“All the time, Mit. You murmur to yourself while you’re thinking, and you subvocalise throughout the day. There’s very little about your thought life I don’t know. Or your fantasy life. You’re whispering to me almost all the time.”
I sat back, bouncing a little as I forgot to adjust the move for the low gravity.
“Oh.”
“It’s nice. I like it. It makes me feel very intimately connected with you. Why? Does it worry you?”
“Not with you, no. If I can’t trust you, I might as well give up now. But I suppose that means you know all sorts of things that I have never told Shayna.”
I considered that soberly, while she was tactfully not replying. It was definitely something to think through on another occasion.
“But anyway, when the hand-held had been compromised, and that other thing was quizzing me, I started to wonder how much I was giving away. Or how much the Wise Man was learning without me knowing.”
“While you were in his quarters, he would have had a direct link from the hand-held into his main system. It was a very old model Ziggurat, like I said before, not very responsive at all. Male gendered, but only just. Badly set up and very poorly programmed. But he has the name Hunn Gravfelt, which at least shows that one of them has read a few decent books. Very arty. But anyway, once you left there, he had no way of querying the hand-held until you got linked up to a ground system. He’s a shady character, but not a very competent one.”
“I suppose the big question is how much information he now has.”
“Yes. But actually, we don’t know for sure what he was able to derive while you were on Agnes. We deliberately left a lot of material out in the open, so he would find it easily enough. We now have to wait and see where that turns up. Like the breadcrumbs in the old children’s stories.”
“But he doesn’t know anything I said on the way home?”
“No. There was a very large data packet all ready to be sent back, but it was never buffered. Do you want to know what was in it?”
I stayed silent and thought about it for a long time, and Slate stayed silent with me.
“Don’t tell me the details. But do run through it again, and tell me if I was about to give away anything critical to the job. Or that might have put Shayna at risk.”
There was a very short pause.
“Nothing like that. If Yul Yulsson was a voyeur, and if he’d ever received it, he could have had some fun with it, for sure. But he would not have learned anything of real value. There’s actually more about me in the packet than Shayna.”
“Hmm. Best not to tell her that, if you don’t mind.”
“This can be our secret.”
I moved to the cabin, pulled out some of the new pieces of clothing which, so far as I could tell, would help me fit in at the Frag Rockers bar a lot better than the formal garb I had worn to see the Wise Man.
“Slate, who’s leading at Frag Rockers tomorrow?”
“A prog rock fusion band called The Descenters. The keyboard player and drummer are locals, from St Martins and Tresco respectively, and the rest are from Ceres. They have a very big fan book on SystemPlus. They’re best known for extremely long concept gigs. They lost their way a bit with Trails on Topological Notions – the twenty-eight minute triangle solo called Geodesics confused even their best fans. But then the electro-gamba player left, and they built up their reputation again.”
“Will I like them?”

Next up, in another book, Mit is discussing a recent shipwreck with his friend Parvati…

Timing (follow this link)

Timing Kindle cover

I wanted human company again, so I stretched and went in search of Parvati. She was brewing chai as I wandered in to the kitchen. Seeing me, she doubled up the amounts, found a second mug, and arranged some savoury crackers and a red and yellow striped cake on a tray.
“Did you and Slate get anywhere?”
I shook my head.
“Total blank. The figures don’t tell us any more than the basic alert message we got from Finsbury, and they won’t let us access the code yet. There’s almost nothing we can do until we get there.”
We moved back to the bridge and enjoyed the snack together.
“Chandrika just picked up the latest from the wreck site for Selif’s ship, if you’re interested?”
I very definitely was interested. We finished the crackers, and she sliced two generous portions of the cake.
“They’ve made available the results from the data recorders. There’s nothing at all unusual until about three minutes before the crash. At that point, Selif took the vessel’s riding lights offline and uploaded an amendment to the nav plan.”
“Presumably to avoid being identified by the duty porters?”
“Most likely, yes. You’re not supposed to disengage them, but people do. As you say, he was motivated to slip in without attracting attention. It’s also uncommon to amend the plan at that late stage, but it happens. Anyway, the upload was completed successfully, taking only the expected lag. Except that a couple of seconds later, both recording devices ceased gathering data. At the same instant. That is unheard of.”
I looked at her.
“How did that happen?”
“The maintenance log for the recorders showed that Selif had skipped two routine services. So they highlighted that in the report, and almost immediately the manufacturer put out advisory notices basically denying all responsibility if people ignore the recommended schedule. So the official version simply lists an open verdict.”
“Is there an unofficial version?”
She grinned.
“Of course. Chandrika, why don’t you tell them?”
“To be sure. I heard this from one of the personas on Martin’s. He works part-time with a man who’s an expert on the embedded systems in boat engines.”
I nodded. It was a highly specialised area, and one that I knew next to nothing about. But it made sense that a man with those skills would have an opinion on data recorders.
“Well, he said two things. One is that a full restart cycle for those boxes is about half a second longer than the time from the point of failure up until the impact on Teän. And the second thing is that there are only two known exploits for that model of recorder which could bring down both boxes together. One of them cannot possibly have anything to do with this case: a different ship configuration altogether. The other one happens to rely on a routing plan change.”
I sat there, absorbing the news. It made sense that these units would go into an automatic reboot mode if they went dark for some reason. Normally that would restore them to full operation in plenty of time to carry on doing their job. But in this case, the boat had hit Teän before they had started up again. I stirred in my seat, but Slate beat me to it.
“That’s very precise timing on someone’s part. Does anybody think it is just a coincidence?”
“Oh, Slate, the official verdict is open. Nobody is suggesting anything.”
We all laughed together.
“Either it was phenomenally bad luck on their part, or…”
I paused, and Parvati continued.
“Or else someone wanted rid of them, and found a clever way to do it.”

Why the Countdown deals? Well, the last day of October marks the last day of my current job in London. I shall be opening a new phase of working life up in Cumbria. Expect more posts about life up there.

So it seemed fitting to post some extracts, and to discount on Kindle, my science fiction series where coding, AI, and financial fraud in space are the main themes.

But I’m not saying goodbye to that style of writing! As regular readers will know, The Liminal Zone shares a lot in common with those books, though it has a different focus and is set a couple of decades further in the future. And behind that, the third in the Spaceports series is toddling along, tentatively named The Authentication Key at present.

Next week’s post will still be from London, but the one after that will be from Grasmere. And don’t forget… there’s a week of Countdown deal on each of Far from the Spaceports and Timing!

Science, Science fiction

Back to life on other planets…

October 10, 2018 RichardAbbott Leave a comment

Our solar system - comparison of sixes (BBC) — Our solar system – comparison of sixes (BBC)

It’s a while since I added to my occasional series concerning the exploration of life on other planets, so here are some thoughts about the giant planets in our solar system. Largest of all is Jupiter, followed by Saturn, then Uranus and Neptune. Each of these has a collection of moons, but I’ll deal with them another day. We also know of a number of exoplanets of this size circling other stars – big planets being easier to detect than smaller ones, other things being equal – but that’ll be the subject for another day.

These large gas giants are characterised by hugely deep atmospheres, in which the pressure rapidly builds to intolerable levels as you drop down through it. It is unclear whether there is a hard surface at any point, or whether the gases of the upper layers simply get progressively denser and more viscous with depth. With no obstructions to stop them, wind currents circle the planet and stir up giant storms that can last for decades. It is not an obvious place for life to thrive.

Spacehounds of IPC - cover (Goodreads) — Spacehounds of IPC – cover (Goodreads)

Science fiction writers have, nevertheless, speculated about life here. Some authors simply ignore what we know (or were writing at a time when much less was known), while others try to weave their stories alongside the facts as we understand them. Typical of the first is EE (Doc) Smith, who was never shy of hypothesising life anywhere, and took great delight in speculating how environmental pressures would shape an alien race’s outlook on life, as well as their physiology. He placed several races on gas giants, including Jupiter. Such races, in his view, would be not only squat and strong – to cope with the gravity – but arrogant and condescending towards the weaklings of other worlds. A large part of Spacehounds of IPC deals with a long-running war between the hexans and the Vorkuls, inhabiting two opposing cities and fighting an impeccable war against each other. The Earthlings help resolve the fight by siding with the more morally upright side – they have little enough in common with either, but the hexans turn out to be unacceptably vicious and ruthless.

The Algebraist - cover (Goodreads) — The Algebraist – cover (Goodreads)

Iain M Banks, on the other hand, tried to take a more nuanced view. A couple of his books – including The Algebraist, for example – present life on gas giants as essentially floating, by analogy with oceanic creatures here on Earth. Different kinds of life coexist at different levels of the multi-layered atmosphere. Some of these interact, for better or worse, and others never meet.

Current scientific thinking is less optimistic about life of these giant planets, preferring to think about their moons. That’s a subject for another day. But there was a fascinating piece of analysis I read recently, trying to tackle the question of whether denizens of the gas giants would develop space travel. Basically, the rocket problem is that of managing your fuel. You need a certain amount of fuel to send your object of interest – the payload – up from the surface to orbit. But the payload has a protective casing, which you don’t need in orbit but which weighs something. Then there’s the fuel you’ll burn, and the container holding it… and these also weigh something. So you need more fuel to push up all that lot… and so on. Think back to how small the Apollo moon landers were compared to the entire Saturn V launch system.

The most fuel-efficient way to accomplish this is to have booster stages that are used in the early part of the flight, and then detached when empty to reduce weight for the next stage. Until the advent of reusable vessels like the Space Shuttle, and more recently Elon Musk’s launch vehicles that return to a soft landing, all of these lower stages were single-shot throwaway items. Now, that’s a problem for us here, but in turns out to be a much bigger problem if you are starting from a larger planet. Even one twice Earth’s mass would present difficulties, and Jupiter has about 300 times the mass. Musk’s Falcon Heavy rocket can place about 50 tons of payload into low earth orbit. Taking off from Jupiter, the same rocket could only get 40 kilograms into space. Would a race of beings living on one of these gas giants – even supposing they wanted to look through dense layers of cloud to see what was outside and spark their curiosity – have the resources to embark on space exploration?

One of Cassini's last images of Saturn (NASA/JPL) — One of Cassini’s last images of Saturn (NASA/JPL)

Science, Science fiction, The Liminal Zone

Weather – away from Earth

October 3, 2018 RichardAbbott Leave a comment

Last week I talked about weather on Earth, both in fact and fiction. This week, suitably enough, it’s time to think about the other planets in our solar system. And there’s plenty to talk about.

Dust storm front, northern latitudes of Mars (ESA Mars Express)

The obvious first place to start is Mars – the atmosphere is thin there (ground level on Mars is about the same as 30 km altitude here, high above the Himalayan peaks), but it’s well able to have weather patterns. There are seasonal changes, with the polar ice caps (frozen CO2, or dry ice, rather than water ice) growing and shrinking as the planet tilts one pole or the other towards the sun. Then there are erratic changes, such as dust storms which can build up over a substantial area. The Martian opened with one such storm, and the book version had a second which threatened Mark Watney’s journey towards rescue (the film skipped over this one). In the real world, back in the summer, one such storm of vast proportions cut off communication between NASA’s Opportunity rover and mission control. The problem here is not actually caused by fierce winds buffering the craft, but that the dust has blocked its ability to capture sunlight and so generate electricity (the exact problem Watney faced late on in The Martian).

Storm on Saturn seen by Cassini probe, 2010 (NASA)

Venus has ferociously fierce winds, and if ever we try to build a permanent settlement on the surface there (which personally I doubt, since orbital or high atmospheric bases would probably suffice) then they will need immensely strong anchors, and extraordinary resistance to high levels of heat and acidity. There are outline plans at present for building a lander able to survive for a few months, rather than the few hours which is all that has been achieved to date. Jupiter and Saturn have no discernible surface – probably one exists, but the pressure would be intolerable well before you reached it. They also have huge storms spreading thousands of miles across.

Artist's impression, dust storm on Titan (PGP/Labex UnivEarthS/University Paris Diderot – C. Epitalon & S. Rodriguez) — Artist’s impression, dust storm on Titan (PGP/Labex UnivEarthS/University Paris Diderot – C. Epitalon & S. Rodriguez)

But several of the moons of the giant planets are more promising. Recently, dust storms were spotted on Saturn’s moon Titan… not sand as might be on Earth or Mars, but great clouds of organic hydrocarbon molecules are stirred up into its atmosphere. So there’s definitely weather on Titan, and pretty much everywhere else we look.

Moons like Titan have been known to have atmospheres for some time, but as well as this, our solar system contains a lot of small bodies which used to be thought of as entirely airless. Closer investigation has shown that many of these actually have very thin layers of air around them. In some cases these are probably generated by underground deposits of liquid and gas which slowly ooze to the surface and evaporate. In others, we don’t yet know how they came into being. But these discoveries are reshaping how we think of our sibling worlds, and by extension the worlds we are spotting around other stars.

New Horizons image of clouds on Pluto (NASA/JPL)

Back in 1950, EE (Doc) Smith, in First Lensman, could describe Pluto as being rocky and entirely barren. We couldn’t say that any more, not after the New Horizons probe sent back this fantastic image of air and clouds above Pluto. In Liminal Zone, my protagonists on Pluto’s moon Charon witness such changes both outside the dome where they live, and also when they look up at Pluto. Weather, it seems, is pretty universal, and will go on forming a topic of conversation for a lot of years to come.

And in a final stop-press, the existence of a new dwarf planet has just been announced. The finders were actually looking for the enigmatic Planet Nine, whose existence is suspected from a variety of gravitational anomalies in the orbits of other far-out objects. That has still not been detected, but instead they found 2015 TG387, dubbed The Goblin for simplicity. This newly recognised member of our solar system has a fantastically elongated orbit. At closest approach it is still well outside the orbit of Pluto, and at aphelion it strays 35 times as far away. It takes around 40,000 years to complete an orbit: last time it was in its present position we were sharing much of the planet with Neanderthals.

Orbit of 2015 TG387 (Roberto Molar Candanosa and Scott Sheppard, courtesy of Carnegie Institution for Science)

Science, Science fiction, The Liminal Zone

Red dwarf stars, and life away from Earth

September 12, 2018 RichardAbbott 2 Comments

After a few weeks in which I have been thinking about ancient Cumbria, this week I’m back in space again. In particular, this post looks at some possible locations for alien life which, until recently, were considered most unlikely. Over the last few years, thousands of planets have been identified by equipment both on Earth’s surface and in orbit. We now know that planets are exceedingly common in the galaxy, and that on average, each star has more than one planet. There are more planets near us than stars. Many of these are large in size, gas giants like our own Jupiter and Saturn – larger planets are obviously easier to detect than smaller ones – but a great many are small and rocky, more like Earth.

Artist's impression - the seven planets of TRAPPIST-1 (ESO) — Artist’s impression – the seven planets of TRAPPIST-1 (ESO)

The most extreme case we know of is designated TRAPPIST-1 (the acronym originating from the Chilean telescope which first detected them). This has seven planets, so the system is broadly like our own. And a very recent analysis suggests that each of them has liquid water at its surface, and in some cases considerably more water than we enjoy here. If we were to travel the forty light years to get there, we might well find a world which is entirely ocean.

But as well as the striking nature of the planetary system, the sun itself is interesting. Up until fairly recently, the search for life elsewhere was focused on stars which were as similar to our sun as possible. It was assumed that this was necessary in order for the associated planets would be like Earth. But TRAPPIST-1 is not at all like our sun – it is a comparatively cool red dwarf star. Red dwarfs are extremely common in space, but they are small and dim, and until modern orbital telescopes revealed the true situation, were thought to be rare.

Now, red dwarf stars are much cooler than our sun, between 1/3 and 2/3 of the effective temperature, so for a planet to be in the Goldilocks Zone – neither too hot nor too cold – it must be much closer to its sun. But that’s OK – in the TRAPPIST-1 system, all seven planets orbit well within the distance that super-hot Mercury circles our sun. Indeed, that system is not much larger than that of the moons of Jupiter. Red dwarfs are miserly with their energy, so you have to huddle in close to the fire to get any warmth. But along with that, they burn at their low rate for a hugely longer time than our sun will last. The hotter and brighter the star, the less time it shines for. Too short a stellar lifetime, and their might not be time for life to develop on whatever planets are around. Red dwarfs give their planets massive amounts of time to develop.

Right now we have absolutely no idea whether any of the TRAPPIST-1 planets supports life – or indeed any of the myriad other red dwarfs and their planets in our quadrant of the galaxy. But if you were a betting person, you’d be more likely to bet on life arising around a red dwarf than a super-hot star like Sirius.

Artist's impression, Ross-128b (ESO) — Artist’s impression, Ross-128b (ESO)

Now, 40 light years is inconveniently far away from Earth for exploration in reality or fiction. Our current generation of telescopes can find out a decent amount of information about the 7 planets of circling TRAPPIST-1, but not nearly as much as one would like. And if you consider near-future science fiction, without warp drives, wormholes, or other exotic ways to travel around space -as I do – then 40 light years is well beyond a realistic journey time. Happily, there are other red dwarfs much closer to us. One of these, which has been studied with great excitement for a few years now, is called Ross 128 (the rather boring name coming from a catalogue number). It has at least one planet (Ross 128-b) which appears to be a little larger and more massive than our Earth, and some calculations suggest that its surface temperature may well be around 21C. Ross 128 is only about 11 light years from Earth, so is getting towards the we-might-send-something-there territory.

I thought about using Ross 128 as the focus of interest in my in-progress novel The Liminal Zone, but in the end pitched for the even-closer Gliese 411 – another catalogue name, which for fictional purposes has been rebranded something more interesting. Gliese 411 is under 9 light years away, and is the 4th-closest star system to us. The planet Gliese 411b is, so far as we can tell, larger than Earth, and almost certainly rather hotter, but (probably) not so hot as to preclude interesting things there. And its proximity to us makes it a credible target for the Breakthrough Starshot project, in which tiny “spacecraft” with roughly the capability of a mobile phone are boosted towards their target by a laser beam shining against a light-catching sail. The miniature spaceships are called Sprites, and last year were tested for their ability to communicate from space after being launched from Earth. Each is just a few centimetres square, weighs just 4 grams, and costs a few tens of dollars. The entire actual cost of the mission is in the devices needed to boost these Sprites to their final speed.

Starshot’s current plans are for Proxima Centauri as target – the nearest star to us, a little over 4 light years away – and a boost to 1/5 light speed. Proxima Centauri is in fact another red dwarf star, and a very recent theoretical study suggests its planet may have a large ocean and survivable temperatures… though so far we lack real observations which might confirm or refute this, and other studies have suggested that the radiation levels are uncomfortably high for life to thrive.

My fictional version is a little more ambitious – Gliese 411 and 1/2 light speed. A journey time of about 17 years, plus the time taken for the homeward bound signal on arrival, means about a 25 year lag from lift-off to analysis of results. It’s still a long time, but less so than some space projects – it is now over 41 years since the two Voyager spacecraft left Earth, and we are still following them. A very recent theoretical study

As to what happens in The Liminal Zone once these little ships get there – well, it’s still work in progress, but hopefully you’ll get a chance to see for yourself early next year!

Extract, Science, Science fiction, Timing

Life on Mars in fiction

July 31, 2018 RichardAbbott Leave a comment

For today I am going back to my series looking at how writers have thought about life elsewhere in the solar system… and it’s the turn of Mars this week.

Cover - The War of the Worlds (Goodreads) — Cover – The War of the Worlds (Goodreads)

It’s fair to say that Mars has been a firm favourite of writers for a long time. The discovery by the 19th century astronomer Schiaparelli of surface markings which he called canali – immediately if incorrectly Anglicised to canals – spurred a vision of Mars as a dying planet. In this vision, the inhabitants were desperately husbanding their dwindling water resources to delay their inevitable fate. This picture of a dying world drove HG Wells’s The War of the Worlds, and a host of other books including CS Lewis’s Out of the Silent Planet, though in his religious reworking, the cause of decline had less to do with natural process than spiritual.

The question that authors faced, then, was how long ago had the surface been benign and habitable? Authors like Leigh Bracket pictured open lakes and oceans in the past, providing a lush surface life a few million years ago, but all now swallowed up by the deserts.

Cover - Sea Kings of Mars (Goodreads) — Cover – Sea Kings of Mars (Goodreads)

Oddly enough, this is not a very different picture to that painted by scientists from the data returned by surface and orbital probes… though the timescale is hugely different. Yes, it seems that Mars did once have running water, but instead of the time period that Leigh Brackett (Sea Kings of Mars) proposed, we are looking at an interval much longer, more on the scale of billions of years. Surface features such as rocks formations shaped by running water have been found, as well as exposed layers of ice threading in between rock strata. Most recently, evidence has been shown that a large salt-water lake may still exist at a considerable depth below the Martian south pole. All this water has kickstarted the debate about life on Mars, by analogy with microbial life found here on Earth in the seemingly inhospitable cold under the Antarctic ice.

A number of authors have tackled the question of terraforming Mars – Kim Stanley Robinson for one, with his (extremely long) trilogy beginning with Red Mars. This basically looks the other way at the situation – rather than how a once-habitable Mars declined into its current state, how might we reverse this process and restore a decent atmosphere and surface water? If possible, it would be a very long-term goal, and it’s not clear how the process would resolve some of the other Martian issues such as excessive radiation. It seems more likely to me that, at least for the foreseeable future, living on Mars will have to be done under domes, not out in the open air.

Meanwhile, here’s an extract from my own vision of a near-future Mars, taken from Timing. Mitnash and Slate are on Mars, at a financial training school. One of the staff members, Linnea, has come to them and is describing a recent hack during which the school was held to ransom…

She hesitated for a long moment, then nodded.

“That will have to do. That night, the system locked up completely. The infra team tried their best to recover, but they had no idea what was wrong. Neither of the main hubs would boot up. It’s some sort of paired system, I don’t know the details, but they’re twins, certainly. One of the technicians said it was like they had gone catatonic. In a coma. Now, four or five days before that, every staff member had received the same message, an ultimatum threatening to close us down if we didn’t pay a ransom. Principal Pulkkinen told us all to ignore it, said it was just a prank. Well, we all thought he was right. Nobody would have done anything different.”

She glanced around. I tried to look reassuring.

“So what happened then?”

“Well, that night, just when the message predicted, that’s when the system crashed. And all the staff screens showed just one message which couldn’t be cleared, with a countdown timer and a single button labelled ‘Pay Now’. And there was a ticker showing that the credit being demanded was going up every second that the clock went down. Look, nobody wanted to find out what would happen when the timer ran out. The principal got the department heads together, and they decided quickly enough they would just pay up.”

“But you have backups, surely? Why not call their bluff and let the timer run out?”

“That was the first thing we thought of. You don’t get it, any more than we did at first. The whole system was locked, everything. We couldn’t get at the backup storage, or the main comms network, or anything. The techies had no idea what to do. Then we started wondering about the life support. If that was compromised, it’s not just teaching records that would be gone. They say you can’t survive more than about a minute unprotected on Mars. You couldn’t get anywhere safe in that time. And your body would be ruined long before the minute was up. We don’t have suits for everyone. I think we could all get into the trucks at a pinch, just squash in together on the way over to the shuttle groundstation. But what if the trucks wouldn’t work either? What if they had been hacked and wouldn’t go where we wanted? It was a nightmare.”

She shivered at the memory, her arms wrapped round herself. I could empathise with her. I was imagining the situation – the teachers at a loss what to do, the students still oblivious, the senior staff ensconced in a room trying to make a difficult decision. With a deeply inhospitable world just outside the dome, and no guarantee that the environmental controls would continue to function.

“So Mikko decided to pay?”

And I couldn’t possibly close this blog without linking to Dave Bowie… Life on Mars?

https://www.youtube.com/watch?v=v–IqqusnNQ

Extract, Far from the Spaceports, Science fiction

Embleton Bay (and an extract from Far from the Spaceports)

July 24, 2018 RichardAbbott Leave a comment

Last weekend I was up in Northumberland, and on the last day – Sunday – visited Embleton Bay. The last time I was here I was walking the Northumberland coastal path, heading north towards Lindisfarne. This time it was just a short walk along the beach, and for some of the family, a splash in the sea.

Embleton Bay is one of the many scallop shaped dips in the northeast coastline. It is low, with dunes on the landward side rather than cliffs, and the view to the south ends with the splendid ruins of Dunstanburgh Castle, dark against the vivid blue sky.

Embleton Bay happens also to be the location of one of the flashback scenes in Far from the Spaceports. Here, we meet Mitnash and Shayna camping (in what is admittedly a very high-tech tent), before Mit gets sent offworld to the asteroids called The Scilly Isles. Looking at the view last Sunday, it was not too difficult to imagine the two of them pitched here on the border between dunes and beach. It was a last opportunity to enjoy each other’s company – and in Mit’s case, the delights of open air and water – before being parted. I’ve added an extract below…

Shayna has probably had the thin end of the story so far, but as and when I write the third book in the series, provisionally called The Authentication Key, she should get more narrative attention!

And just to keep the Northumberland theme going, here’s Mark Knofler from YouTube, with a rather different mood than his better known riffs…

And here’s the extract…

I was away in the Northumbrian national park, walking the Bernician Way with nothing but one of the recent model v-tents and Shayna. Neither of us were at all interested in walking long-distance footpaths, but we both liked the absence of neighbours. A couple can make a lot of noise out in a national park, without thinking someone else might be disturbed.

But there it was, that morning, the message alert blinking silently on my shirt lapel where I’d discarded it for swimming in the North Sea last night, almost hidden by Shayna’s NuFleece. She might not like long distance walking, but she loved the prospect of skinny-dipping in sea water not far above freezing, and then thinking of inventive ways to warm up. That was so much easier when you could come out of the water and straight into a v-tent micro environment set at whatever climate you wanted. Right now we were in a Middle Egyptian May – temperature, humidity, everything.

Shayna liked to say that the chosen location was part of her genetic heritage, and she was in search of her roots. I was never sure about that, but I had no great preference myself. She had configured it just as soon as I had set the tent up, and it had taken under a minute to climatise itself.

So all through the night, with a North Sea winter gale blowing up and down outside, there we were in the Valley of the Kings. You didn’t mind so much going into cold water with all that warmth waiting. We’d polarised the fabric, silver from the outside and clear from the inside, and we lay together watching the half moon slide in and out of the curving clouds.

We’d arrived at low water, but I’d pitched the tent well up the beach, on a strip of pale sand between some levels of flat rock. High tide was in the early hours of the morning, and the waves had washed close up against us in the cosy dark.

I scowled at the lapel badge, wondering if there was any way to pretend I had not seen it. There wasn’t, not really. Slate would have acknowledged receipt of the incoming at the same time as redirecting it, and would have tagged its reception with all kinds of logging. It was far too late for me to try hacking anything. The real question was whether I could get away with avoiding it for more hours than I had already, but I already knew the answer to that one as well.

I tapped the lapel, and listened to the message sullenly. Recalled to London… first opportunity… Twelve hour SLA. I sighed, and entered the release commit. Slate would do the rest for me. Then I turned to look at Shayna. There she was in the morning light: brown skin enjoying the warm air, dark hair spilling over the pillow, and dark eyes opening with an air of frustration as she saw me working the lapel.

“I suppose you’re going to say there’s no more holiday now.”

I nodded.

“Recall at first available. Back to London for me.” I paused. “You could stay here?”

“Oh, Mit. Where’s the fun in that?”

She closed her eyes again briefly, but I could see the little muscle movements in her face as she interrogated her Stele. Rocky, she called him, and he was male in persona as well as voice. It was fair enough: Slate was undeniably female.

“We have three hours before the east coast express stops at Alnmouth. A quarter hour to pack up, half an hour to Craster, quarter hour transfer. That gives us another swim and time to warm up again afterwards.”

I loosened a vent a notch or two, listened to a sudden gust of wind, imagined what the air and water would be like.

“We could miss out the swim and just stay warm?”

She reached past me and tapped the door release, inviting the gust inside the tent where it contended unsuccessfully with the thermal regulation.

“Wherever it is they are going to send you now, you won’t have water like this. Out you go and enjoy it one more time.”

I shook my head, but got out and stood up anyway, naked in all that volume of cold rushing air. The tide had fallen again, and the sea froth was a little way down the beach. Shayna pushed past me and ran, arms waving above her head, shrieking with excitement as the wildness of the wind encircled her soul. I followed on, but she reached the water well before me, and threw herself in to the tumble of the waves.

Twenty years ago I would never have done this, but things had changed. Anyway, she was right: wherever I was going, it wouldn’t have wind and waves like this. I followed her.

…

It had been a long day. An icy bathe first thing in Embleton Bay, followed by Egyptian warmth. Then down to London for the first briefing, and some intense training sessions on commodities. Slate had uplinked a whole library of reading material on the subject, from finding the stuff right through to trading it. But I stopped at the point of trading, and even today I have very little idea how rare earths are actually used. But by the end of the journey I would sound totally convincing on the important parts of the subject. Finally, a second briefing with Elias, and a scramble to Euston to catch the overnight to Findhorn.

I had intended to gaze forlornly out of the window as I hurtled past Alnmouth again, this time heading north. However, fatigue had got the better of me and I was dozing at the time, propped up in a corner. I surfaced again somewhere well north of Dundee, just as it was getting light. On the east coast line, most of the trains stopped in Edinburgh, but this was the Spaceport Special, non-stop right the way through.

Far from the Spaceports, Science, Science fiction, Timeline

AI in space… or, how close are we to Slate?

July 4, 2018 RichardAbbott Leave a comment

There has been a whole bundle of space news this week – so much, in fact, that I had to temporarily postpone my series of going through how the different planets have been portrayed in fiction. Instead, I picked a couple of key stories which most appealed.

The western side of Cerealia Facula, from an altitude of about 21 miles (NASA/JPL-Caltech/UCLA/MPS/DLR/IDA)

The first – and much the shorter – is to do with the Dawn space probe. Readers may remember that a few months ago, the decision was taken to use the remaining fuel to lower the orbit as far as safely feasible. This means better images (and results from other instruments) as the orbit now goes down as low as about 20 miles. The first pictures have started to appear, and very striking they are, and over the next few months I expect that we’ll be hearing a lot more about the surface chemistry. The first approach to Ceres revealed enigmatic bright spots on the surface (known as faculae), which are now recognised as salty deposits of carbonates – the largest such deposits away from the Earth, in fact. But do they ooze up through cracks and fissures from deep underground, or is there a reservoir of brine just below the surface? It is possible that the new low orbit wil shed light on this.

But the main story-telling event of interest was part of the contents of the Soyuz shuttle which docked with the ISS a little while ago. As well as three crew and a bunch of science experiments, a mobile AI called CIMON (Crew Interactive MObile Companion) arrived…

CIMON - the first AI crew assistant for spaceflight crews (Airbus/NASA) — CIMON – the first AI crew assistant for spaceflight crews (Airbus/NASA)

CIMON is powered by the IBM Watson software, has a digital “face”, and is capable of interacting with the Station crew via facial expressions, emotions, and voice. Excitingly – so far as I am concerned – CIMON is European in origin, having been developed by Airbus. The enclosing shell was 3d printed, and weighs about 5kg (which only matters if it collides with something, as the ISS is routinely in microgravity). It wil remain free-flying and able to navigate to the various parts of the ISS at need.

CIMON has several purposes – first, it gives the internal neural networks plenty of new material to learn from, but the intention is that the crew will work with the AI to find collaborative solutions to problems. The science objectives are listed as:

The Pilot Study with the Crew Interactive MObile companioN (Cimon) is a technology demonstration project, and an observational study, that aims to obtain the first insights into the effects on crew support by an artificial intelligence (AI), in terms of efficiency and acceptance during long-term missions in space. Spaceflight missions put the crew under a substantial amount of stress and workload, and it is thought that AI could provide operational support to crew members.

So although CIMON can certainly provide early warning of particular categories of technical problems, and will assist with a number of predefined experiments, the goal is to provide social interaction.

Which brings me, naturally, to Slate! Slate, the main persona AI in Far from the Spaceports, is several generations of AI beyond what we enjoy today. Voice assistants like Alexa, Google Home, Siri, Cortana and so on are currently Earth-tethered in the sense that the software and database needed to comprehend and respond to a user’s request lives in cloud-based servers here on the planet. Even a trip to the moon (just over a second light signal time each way) would seriously strain conversational ability, and a trip out to the asteroids – say half an hour signal lag – is entirely out of the question. I don’t know whether CIMON relies on Earth-based data to understand what the astronauts will say, or whether a data source has been uploaded to the ISS itself. Keeping tethered to Earth would certainly be feasible at the ISS orbital height – but to go further afield we will need to crack the problem of large-scale localised data storage (maybe using DNA?).

I’ve never committed to an exact year for the events of Far from the Spaceports or Timing, but my feel is something like a century. I feel that probably I have been a little too cautious with this, and that in reality there’s a fair chance that AI having close to Slate’s capabilities could be around within my lifetime. On the other hand, my guess is that human colonies out at and beyond the asteroids won’t be around for a few years after my guess, so maybe it evens up!

Meanwhile, here’s a YouTube video (at https://youtu.be/KnpJI3WeiBg for those getting this through email) showing part of CIMON’s development…

Science, Science fiction, Writing

Mercury and fiction

June 27, 2018 RichardAbbott Leave a comment

Last week we looked at how views of Venus had changed in fiction: this time it’s Mercury’s turn. Like Venus, Mercury is never visible far above the horizon – indeed, it never gets above 17 degrees here in London, less than half that of Venus. It’s another morning and evening star candidate, though far fainter than Venus, and far easier to miss unless viewing conditions are good. In classical times, Mercury was the swift messenger of the gods, presumably because of his elusive presence, rapid shift across the sky, and proximity to the sun.

North polar region of Mercury, false colouring showing (probable) water ice (NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)

Once telescopic study of the planets began, it became obvious that Mercury was going to be pretty inhospitable. It orbits at just over 1/3 of the Earth-Sun distance, has virtually no atmosphere, and experiences temperatures up to 450°C on the sunlit side (oddly, that is much the same as Venus, but for quite different reasons). Lead, zinc, and a whole bunch of other metals would melt under these conditions. Bizarrely, even here, there are a few shady places where water ice can still exist on the surface – water is one of the most persistent and universal features of our solar system.

For a long time it was thought that Mercury was tidally locked, always showing the same face to the sun. More recently we have found that this is not the case – Mercury’s day is 59 Earth days, while its year is 88 Earth days – 2 Mercury years contain just 3 Mercury days. The combination means that every time Mercury is closest to the Earth, we see the same surface features… one of those mutual rhythms which appear all over the solar system.

You’d think that fiction writers would struggle to place a story on Mercury, but numerous people have tried. ER Eddison, in his fantasy series starting with The Worm Ouroboros, located his events there – though he was singularly unconcerned with the real planet, and simply used “Mercury” as a handy, mysterious location, at which very Earthlike deeds took place. In his writing, Mercury is simply an elsewhere location outside his readers’ everyday life.

When it was thought that Mercury was tidally locked, several authors assumed that humans would build a settlement somewhere on the dividing line between unbearable heat and implacable cold. Plots often revolved around the (supposed) vast difference between light and dark sides. For example, Hugh Walters’ Mission to Mercury supposes that the extreme heat (and cold) would lead to different personality problems (interestingly, this book also features another occasional trope, that of identical twins who can communicate telepathically).

The discovery that Mercury actually does rotate put paid to the idea of a temperate band, leaving us with a largely undesirable planet! It is a long way “down” in the sun’s gravity well, so needs a disproportionate amount of fuel to get there and back. Unless there turns out to be plentiful and easily accessed resources of some kind – gloopy patches of pure platinum, or some such – then it’s hard to see why it would ever be more than a solar research base. Authors and technologists have contemplated terraforming Mars (of which more next time) or Venus (AE van Vogt suggested that it could provide an exotic home for the elite in The World of Null-A) – I can’t think of anyone who has suggested terraforming Mercury! Kim Stanley Robinson, in several novels and short stories, suggested one solution would be a city built on rails which very slowly moved around the planet and hence always stayed in the twilight zone.

In fiction, it has become, and most likely will remain, a hostile place which might contain or provoke mystery. And in keeping with that, I’m not (currently) planning any books in my science fiction series which are set there.

Finally, you’re not (quite) too late to take advantage of the giveaway offer on the audio version of Half Sick of Shadows – details in a former blog post…

Writing Slate