Chris McMahon's Blog, page 6

Voyager 1 Enters Interstellar Space

It’s official, Voyager 1, that Earth-ambassador for 1970s technology, has left the heliosphere – the bubble of charged particles and magnetic fields that surrounds the sun and its planetary progeny. Scientists back-calculated that it likely left this boundary on or around August 25, which coincidentally is when my wife and I hosted the biggest party ever. I knew something had to be in Galactic alignment.

I’m sure I’ve seen this same announcement at periodic intervals over the last five years. Or maybe it was ‘Almost leaving’ those prior times. Because Voyager actually did have to leave before the scientists tracking the spaceship could really be sure it had. This time it really is official. Apparently a fortuitous burst of activity from the sun caused the plasma near the spacecraft to vibrate, which allowed scientists to calculate how much was present. The plasma beyond the heliosphere is about 40 times denser than inside it, giving the clues that pinned down Voyager 1’s location. Beyond the heliosphere the plasma (BTW it’s a lot less dense there than around Earth – about 10,000 times less) grows colder and the outward pressure from the sun tailors off, causing it to grow relatively more dense than the plasma inside the limit of the heliosphere.

Voyager 1 is currently 18.77 billion kilometres (11.66 billion mi) from Earth, entering a vast new region of space where nothing else has been before.

So far Voyager 1 has seen the expected drop in solar particles and jump in cosmic rays, but has not observed the predicted shift in magnetic field orientation. No doubt the first of many surprises. Right now scientists are taking another look at the models that predicted this change in magnetic field.

This is a remarkable feat for humanity, but I can’t help but compare this with the sort of achievements outlined in fiction. I recently re-watched Event Horizon, where the experimental ship of the same name returned from some ‘other space’ to Saturn after being missing for almost a decade. Coming through a black hole no less, courtesy of its on-board singularity in the Gravity Drive. So when is this? Why in 2047. The critic in me wonders if we will even have a human footprint on Mars by then, let alone vast spaceships with stasis chambers roaming the solar system.

So are you encouraged, inspired, or left flat by Voyager’s achievement?

Endings

There is often a lot of discussion about crafting the beginning of a story – the first line and following paragraphs. There is no denying a good beginning is essential to hooking a reader or prospective editor. But what about the other end? The end-point of all that structure and character development? The bit that comes before those extremely satisfying two words (at least in the first draft) “The End”.

A good beginning combined with an attractive character might net a sale despite the book’s other faults. With enough marketing buzz it might even create a best-seller, but without that sublime end point, the book is in danger of losing its essential impact.

Perhaps the ending may be less important for books that survive on their characterisation (super-cool protagonists can carry a story through loose or even illogical plots), or that support themselves on superior prose style. But for the other books that lack that well crafted ending, are they destined to drift out of the consciousness of readers as time passes?

So what constitutes a good ending? For me it’s emotional punch and a simultaneously delivered, poignant realisation. A feeling of emotional resolution. When the character arcs have reached their end in a satisfying climax of drama and action that leaves the protagonist changed for the better. I know this does not work for everyone, perhaps seeming too ‘formula’. Some prefer unresolved endings, particularly in short fiction. I think everyone enjoys a surprise ending to mystery that is built well from the beginning (i.e. not ‘the gardener you saw for one paragraph on page 4 did it’).

What do you consider a good ending?

Abduction Report

Reblogged from madgeniusclub:

Hi, everyone. Apologies for my lack of reply to last week’s UFO post, but I was abducted by magical Sidhe folk living in the forest behind my house. As always, time spent in the Sidhe realm follows different rules. Thankfully I did not emerge a day or so later having aged to a ripe old age, but there was definitely some time slippage.

Read more… 375 more words

UFO Buzzes International Space Station!

As the UFO flew past the ISS earlier in the week, NASA astronaut Chris Cassidy was quick of the mark. He caught the object on video as it passed. Of course it did not stay unidentified for long – Russian ground controllers identified it as an antenna cover from the Zvezda service module. See the footage here.

This comes after the US government recently confirmed the existence of Area 51 for the first time. Of course, they confirmed it as a testing area for spy planes, and did not say anything about aliens or crashed alien spacecraft.

The ISS incident got me thinking about UFOs in general, and whether there really has been any alien visitations of Earth in modern times.

Given the vastness of space, and the constraints of physics, I think the most likely alien visitor would be of the robotic kind. Perhaps there has been a probe or two fly past and take so photos. If so, then its next move would be a high-intensity beam communication back to its point of origin. Once more, given the vastness of space, its home civilisation may not pick up the message for hundreds or thousands of years. This of course assumes no advanced SF-type goodies like navigable wormholes or warp drives.

So what do you think? Have aliens visited? Have you seen any truly weird UFOs yourself?

Dealing with the Cast of Thousands

I’m pleased to announce that my fantasy series, the Jakirian Cycle, is finished! All the last edits are done and it should be hitting both the real and electronic shelves around October.

It’s exciting to have completed the trilogy, and it will be great to end the wait for those who started the series with The Calvanni, either in its 2006 Australian print incarnation or its later 2009 electronic version.

One of the things I grappled with Jakirian Cycle (typical of fantasy series) was the considerably wide scope of the story. Without giving too much of the plot away, at the start of The Calvanni the Eathal – the cavern dwelling cousin-species to humans – are launching a major offensive on the remnants of a once vast human Empire. But this is very much in the background.

In the first book the central characters are struggling to survive amid civil strife and assassination attempts (Ellen), while dealing with the emergence of their own unique magical powers (Cedrin).

In the second book, the first major engagements are taking place between the Eathal and the last few human Legions, but the focus is still on the characters and their personal journeys and the mystery of the Scion (the lost heir to the fallen Empire).

In Sorcerer – third book of the trilogy – the clash of human and Eathal occurs on a massive scale. Tens of thousands of human and Eathal troops are fighting across two major fronts. From the PoV of the central characters, they are being drawn more and more into the centre of power in Yos. Both Cedrin and Ellen find themselves right at the core of the reestablished Bulvuran Empire. Amidst all this are the various Warlords who divided up the fallen Empire. The most powerful of whom is facing the Eathal in southern Yos while being heavily outnumbered and under strength in the magical department. To do justice to this, I needed to make that Warlord a PoV character, and needed to portray these major engagements.

Various subplots that have been in the background since the first book all come to the fore in Sorcerer. All of this led to the introduction of a lot of new characters. Each is important to the story in some way, but most are not central or point-of-view characters. Trying to control this crowd, and do them justice was certainly a challenge!

Numerous times I’ve had to scramble back through the book and insert a few key paragraphs. ‘Oh, Damn! Such-and-such was still with Cedrin in that scene.’  or ‘Oh, crap. Where were they when that combat was happening?’ I need to keep them in the picture, but without diluting the thread of the main character too much. There were so many of these minor characters it really proved a teeth-grinding experience. Oh for a simple story! I am my own worst enemy with this. Yet with book three  I also tried to lay the foundation for the ultimate conclusion of what might extend to a possible six books series. Don’t worry – Sorcerer ends with a great climax and the first three books stand as a trilogy.

If you love battle scenes, Sorcerer will definitely be your sort of thing. In that regard it is my homage to David Gemmell:) Using the unique magic of Yos, including the glowmetals, on that scale was a real buzz.

Back to dealing with multiple characters: I always try to maintain the focus of the story through a small number of key point-of-view characters. There may be many other characters introduced to support the story, or to give the setting the feel of the political landscape, but I try to have these experienced through the viewpoint of the key characters. I think it can even aid the tension in the story to have the motivations of these characters unclear – and that’s hard to pull off if they are the narrator. It’s also surprising how much you can convey objectively, without having to make them a PoV character.

It is a tricky balance though. It’s hard to do them all justice, to convey their motivations and to give the reader a sense that these minor characters are moving through the story not just being present as a background cut-out. More than once I shook my head writing Sorcerer and said ‘What the Hell have I got myself into?’

Still, I think it’s worth it to see the various sub-plots come into effect. It gives the whole thing a depth and complexity.

Have you ever been frustrated by the Cast of Thousands? How do you deal with it? Kill them off? Limit their appearances? Tear up your draft?

Is There a Role for Passive Text?

Talking about writing rules, one of the first that got drummed into me (actually, more like beaten into me — around the head with what was left of my frayed manuscript) was the importance of active writing; making the prose immediate, rather than passive. The shorthand for this is ‘Show don’t Tell’. You could do a lot worse than plough through your manuscript with this mantra repeating in your head. Certainly for action, it’s an absolute must. But it really got me wondering — is this really universally applicable?

Some of the books I admired most as a young reader, such as Lord of the Rings, were full of passive text. Huge wads of backstory and enormously long sentences that would never get past a modern editor. Yet it worked. Another book I admire tremendously is Empire of the East by Fred Saberhagen. Accustomed to more modern prose, the passive style put me off initially, but it did not take me long (about two pages), to get sucked right in. That book is an absolute classic.

I guess one of the things that is really attractive about passive prose (often combined with an omniscient PoV) is that it has a sort of reflective power, enabling a deeper level of insight to be injected into the work — be it on the level of character or life, the universe and everything. That sort of thing is difficult with strictly ‘active’ prose. Often tongue and cheek humor also works best in a passive mode (outside of dialogue that is). I think this is one of the things that I tried to emulate in my first attempts to write fantasy, which in my case came off as excessive backstory with overly grandiose metaphors (hey – don’t say anything about PoV!).

The other thing about active prose is that is takes space. I often wonder if there is a case for a blend of active and passive prose, just for the sake of economy. Its a lot faster to say ‘Joe survived the battle, running from the fiends of the Hegemon with his sword between his legs,’ than to go through the whole scene recounting every shiver of fear and blood-filled drop of sweat. If the scene is not really that crucial to the story, but merely a bridge, does it really matter?

Is just makes me wonder. Is passive text total taboo, or is it just one more tool, and perhaps a valid one in some cases?

200 Year Old Technology Makes it into Space – The Stirling Radioisotope Generator

For those of you who have not heard about the Stirling engine, the technology was first proposed by Scotsman Robert Stirling way back in 1816 as an alternative to nasty steam engines, which had a habit of exploding and killing people with high-pressure steam. In nineteenth century steam engines, water inside the pressure vessel was in two phases – steam vapour and pressurised liquid, so in the case of a rupture there was an instant expansion of hot liquid into steam.

Often called an ‘external combustion engine’, Stirling engines are a sealed system with the cylinders inside working with a gas, such as air or nitrogen, which exists in a single phase.

The physical layout of the Stirling engines varies, but all have a ‘power’ piston and a ‘displacer’ that works in concert with the power piston to maintain the constant volume conditions. Each engine has a hot and cold end, with a heat exchanger at each. Inside the engine is a ‘regenerator’,  which is a physical material that stores part of the heat as it flows inside the engine and is crucial to its operation.

Stirling engines have been demonstrated at temperatures well below 100oC. The Ultra Low Temperature Difference Stirling engine was demonstrated to operate at a hot side temperature of just 0.5oC. Like any heat cycle, it is driven by temperature difference, so a low hot side temperature must be balanced by an even lower cold side where heat can be rejected. In practice low temperature differential Stirling engines require a very large surface area for heat transfer and are consequently more expensive to manufacture than high temperature Stirling engines.

The real advantage of Stirling engines lies in their heat source flexibility. The same Stirling engine can operate with a wide range of fuels and over a wide range of temperatures.

NASA have been working for some time on a small Stirling engine for use as a power supply on spacecraft. Called the Advanced Stirling Radioisotope Generator (ASRG), it is driven by the heat from radioactive decay.

Around 1kg of Plutonium 238 forms part of the module. This generates a thermal output of around 500 Watts. The heat drives a small, single cylinder Stirling engine that produces around 140 Watts of electrical power.

Like all Stirling engines, the ASRG is a closed-loop engine. It’s internal working gas will be helium. In its single cylinder the up-down motion of the power stroke is converted into an AC electrical output by a linear alternator. This is then converted to the DC required by on-board systems.

Why would NASA bother putting something with that many moving parts on a spacecraft? Well for a start, Stirling engines are very reliable, and a large part of the work the NASA is undertaking is focussed on reliability studies for the ASRG. But primarily, the ASRG will be four times more efficient per unit mass than the Radioisotope Thermoelectric Generator (RTG) it replaces. That is an impressive increase in efficiency. The RTG modules have been standard on spacecraft for the last 40 years, and use the temperature differential in thermocouples to produce power.

To reduce vibration, two ASRG  units will be mounted opposite each other and synchronised so their pistons move in opposite directions to eliminate mechanical noise.

An RTG system has a typical efficiency of around 5-7%, disappointingly low considering it is driven by 850oC from the Plutonium power source. The ASRG’s Stirling generator would operate at around 38% efficiency with the same 850oC hot end (with heat rejected the lonely depths of space at 90oC). In practice the ASRG’s hot end temperature, and consequently, net efficiency is expected to be a little lower.

The ASRG was demonstrated for the first time in 2012 – the first demonstration of a new nuclear system for power production since 1965. There are also moves to produce more Plutonium, again for the first time since 1965.

The ASRG could be available as early as 2015, and is designed to have a 14 year mission life.

Larger versions have been proposed to power a potential Moon base, and also a Mars base under the NASA Fission Surface Power project. So far a 40kWe version has been trialled in NASA labs (minus the nuclear fuel source i.e. just the Stirling engine component with conventional heat applied). This 40kWe version is likely to be the size of a trash can, and would provide surface power for decades with little or no maintenance.

Around 40 kWe is about the size of generator you need to power a small hybrid-electric vehicle. Maybe NASA would consider selling Plutonium cars to the public? It would be cool to drive around for a couple of decades and never fill up. When you are not driving you could plug it into your house and power both you and your neighbours.

Hey, it’s nice to dream:)

Open Floor

Reblogged from madgeniusclub:

Hi, Everyone. Apologies, but the Dark Forces have combined this week to prevent me from getting my blog together. I've been looking at new power supply technologies for space-based missions and I promise an interesting look at a new application of an old (200 year old) technology next week.

Anyone got any interesting space news?

Characterisation – Fears & Superstitions

Fleshing out characters can be a lot of fun. One popular choice, particularly with horror/suspense writers, is to give the character a particular fear that plays into the story. For example they might have a fear of flying and the big confrontation with the glowing aliens from Mars has to happen on the outside of a racing spacecraft over Manhattan. Or they are afraid of the dark, but to confront the villain they have to go down THOSE stairs into the pitch black basement. This often works well, but can also seem a little contrived if the latter scenes are not woven together convincingly.

But there are plenty of other options. One that is a bit of fun is to incorporate a superstition. This got me thinking about superstitions in general and I thought it might be fun for people to post their own superstitions or those of friends and relatives. Having something from real life like that adds a real element to fiction.

In terms of my family, the one I remember most distinctly is one of my grandmother’s. She used to cover all the mirrors in the house during a thunderstorm. She also used to live in fear of birds flying into windows – it would mean that someone in the family was going to die.

The one I experienced at first-hand was the Irish Catholic practice of dosing children liberally with Holy Water as they lay in bed ready for sleep. You cannot put a price on chasing away the nasty Devil. I kind of liked it actually. Dad used to get his holy water from the St Benedict’s font, and kept it in a little glass bottle. He would pour a bit of Holy Water into his hand and cast away. He had a good technique by the time I came along at number eleven.

There is the old salt over the left shoulder ritual to hit the Devil in the eye if you spill the salt, but that’s never been too convincing for me. What’s the Devil care about sodium chloride anyway?

For myself – I have one that I have never been able to shake that was passed onto me by my mother. If your ears are ringing, it means someone is talking about you. If it’s your left ear it’s something bad – if it’s your right ear it’s something good. You might say I live in fear of left-sided ear infections. This is totally crazy, and yet I can’t shake it. It has a spooky king of logic. If my tinnitus worsens I could be in for permanent paranoia.

What superstitions do you have? Or interesting rituals – the more bizarre the better!

Space X Grasshopper Reusable Rocket

If you’ve been reading this blog for a while, you probably heard me talking about Elon Musk’s Space X and the plans to develop a reusable rocket system. The theory is that it’s the cost of space craft that overwhelmingly contributes to the high cost of getting into orbit. The fuel itself represents perhaps 1% of the total cost. So if you can develop a truly reusable rocket system you can potentially revolutionise space travel. There are a few parts wishful thinking in this, and a few parts hyperbole, but it’s an intriguing concept nonetheless. Meanwhile, Space X is forging ahead.

Space X have been developing a reusable system based on their Falcon 9 launch vehicle platform. This launch vehicle is a pretty familiar sort of beast – a two stage rocket powered by liquid oxygen and kerosene. It has established a solid performance record to date and was used by Space X for a visit to the International Space Station, the first by a commercial company.

The Space X Grasshopper is designed to take the place of the Falcon 9’s first stage. It has been in active testing since September last year. So far it has had six test flights, each gradually extending the height at which the rocket stops, hovers then touches back down. Both take off and landing are vertical (VTVL). The latest (check here for video) took the venerable Grasshopper to 325m (1066 feet), with an overall duration of 68 seconds. It’s likely the tests will extend substantially, perhaps reaching altitudes of up to 91 kilometres (57 mi) with the second generation of the test craft.

If you want a bit of entertainment, check out this video of one of the early tests that plays to Jonny Cash’s ‘Ring of Fire’. LOL.

The second generation of Grasshopper will have lighter-weight landing legs that actually fold up into the rocket. I can’t help but be reminded of those sleek 1950s art-deco SF rockets than come down to land on their legs in such a similar manner, except they (of course) had three legs whereas Grasshopper has four. The Grasshopper’s legs use a telescoping piston on an A-frame, actuated by high-pressure helium.

Plans are to start testing the decent of Falcon 9 first stages to confirm the technology. Each first stage of the Falcon 9 will be equipped and instrumented as a controlled descent test vehicle. They will initially do the propulsive return tests over water until they can complete a return to the launch site with a powered landing, perhaps as early as 2014.

Ultimately the first stage separation will occur at around Mach 6, rather than the current Mach 10 for the expendable version of the Falcon 9. This is to ensure there is sufficient fuel for deceleration, controlled descent and landing.

I have a feeling that once this system is up and running, expendable launch systems will seem like the crazy idea, not reusable ones!

But the Grasshopper, as impressive as it is, is only half the launch system. The first stage will separate and be back on the launch pad minutes after the launch. The reusable second stage will take up to 24 hours to return to the launch pad, to allow for orbital realignment and atmospheric re-entry. Both stages are envisaged to be available for reuse within hours of return.

Eventually the reusable launch system technology will be applied to both the Space X Falcon 9 and Space X Falcon Heavy launch vehicles.

I think we are watching history in the making.