diciembre 2014

On Earth, it is assumed that life started in the water, after all, we do most chemical reactions in some liquid solution or other because it allows molecules to move about, meet each other and react.  Water, being the most abundant solvent, is the best candidate to be the medium where the chemical reactions that lead to life started.

Initial life forms were drifters, that is, the currents, waves, tides and storms were the ones that moved them from one place to another, including dry land.  Populating dry land requires several abilities. As an organism it needs to survive.  As a species, it needs to reproduce. Each of these requirements can be broken down into further abilities which would be very hard to acquire all at once.

Out of the mechanisms that transport drifters, tides are the only one that happens with predictable regularity.  Any living water organism thrown on dry land by a storm  is, most likely, doomed.  Unless it somehow developed while still in the water the means not only to survive but to reproduce, its unexpected fall on dry land is the end of the story for its genetic line.

Tides are the only mechanism that provide a means for drifting water organisms to experience living in a dry environment and return to the water to reproduce and pass on the traits that allowed it to survive.  As the process is repeated over and over, more and more abilities can be acquired and passed on to later generations until reproduction itself can happen on a dry environment.  On Earth, some species like frogs have never developed the ability to reproduce on dry land.  Others either provide a wet environment, be it external such as an egg or internal like mammals, where the new organism can develop.

Can life prosper on land in either of the planets in the novel?  Mother and Heaven face each other showing the very same face much like the Moon does to Earth but in their case, the effect is mutual.  This is called gravitational or tidal locking. Wikipedia has a good explanation for the process. When a body is gravitationally locked to another, it has almost no tides.  It would still have small tides from its sun but they would be irrelevant to our discussion.

Thus, could have land life prospered in Mother and Heaven?  It might but, admittedly, the chances would have been much smaller.  Gravitational locking is a process that occurs over a long time and is not simultaneous, the smaller body falls first to the influence of its larger neighbor.   Life might have settled dry land on the larger planet while it wasn’t still locked to its neighbor.  Life might also develop along rivers that grow and fade with rain.  Most tropical areas on Earth have wet seasons when rain falls regularly every afternoon as the atmosphere cools down and cannot hold that much water vapour in it.  These showers are not as reliable as tides, but they might serve.

So, it might be less likely than on Earth, but life on either Mother on Heaven cannot be ruled out.

As I mentioned in the afterword, initially I thought the planets might have been populated by space travelers, hibernation being a trait genetically introduced on the original travelers to withstand the long travel times. Over time, the sleeping pattern adapted to the day/night cycle of Heaven and Mother, but that seemed a pointless and much abused story line so I dropped it.

Perhaps I should have drawn this map before starting the novel but I did it a couple of days ago. The place changed as the action demanded so it would have required me to keep changing it so I prefered to keep it in my mind instead of grabbing the pencil. Now, since the novel is published, the map is not going to change anymore, so I did it.

Pinnacle City map

Pinnacle City map

It shows just a section of the city. I coloured the water blue, some parks green, the city blocks grey, the railroad station red, the Great Temple pink. The city extends well beyond what is shown in this page but, since no action takes place there, I didn’t bother. The only part missing here is Cape Farsi (chapter 12) which would be further to the right along the Promenade.

Pinnacle is the peninsula at the bottom. The Observatory would be the black circle on the road spiralling up on the fake hill. The Great Temple is the large pink building with the esplanade in front of it, surrounded by other buildings. After the main gate, the causeway leads to the roundabout when it crosses the Promenade and then the big Boulevard of Elvar the Peacifier. To its left is the old city, recognizable by its twisted random streets and then the basin, the port for the river barges. Some non-square city blocks remained on the right hand side of the boulevard which were also part of the old city. The boulevard had actually cut through the old town and new buildings were build facing it, but parts of the old city remain in the back streets.

The sea port is on the left of Pinnacle and a set of locks connects it to the basin. Railroad tracks for cargo run along both the basin, on the far left side, and along the main piers of the sea port. The buildings in that area are mostly warehouses.

Elvar Blvd. ends in the secondary canal, which turns inland somewhere beyond the right edge of this map. The main canal comes from the top left corner which goes past a last set of locks before crossing under the railroad tracks and then entering the basin.

Perhaps the area in between the secondary canal and the railroad station should not have square blocks. It didn’t matter to the story and I felt it was good enough like this. The city would continue on the other side of the railroad station and the tracks, but I didn’t quite bother. Also, beyond the locks on the upper-left corner, branches of the canal should spread into the suburbs and later into the farmland.

Having pods speeding down the ribbon towards either planet is no joke. What if anything fails?

On Earth, something falling from the moon towards the Earth would reach the atmosphere at close to 40 thousand kilometers per hour. That was the speed the Apollo capsules had when they reached the atmosphere where they slowed down by friction. That is why the recent test flight of the new NASA capsule Orion was such a big deal, could the thermal shield protect the capsule? Since Apollo 17, no spacecraft has re-entered the atmosphere at such speed. Orion hasn’t gone that fast, but it was far faster than any man-rated vehicle has since Apollo.

Anyway, back to the novel, what to do with a failing falling pad? If the problem is detected soon enough, the best is to discard it. The two halves of the climber, one on each side of the ribbon, would simply separate and fall away. The easiest and lightest would be explosive bolts, frequently used when separating rocket stages, which would also provide a light push to each half away from the ribbon. From the midway point up to a certain height, the halves would eventually burn up in the atmosphere. It would help if the cargo bay opens and the contents spread, since that would ensure everything burns up faster. However, if this is done very high, the remains might get into orbit. That is not good since in that case, they would eventually return to the point where they had detached from the cable and hit it. That is in theory, in practice, it’s anyone’s guess. Due to many perturbation factors, the chances of actually hitting the cable are small.

The highest chance would be if the two halves are ejected in the direction of the ecliptic, meaning one eastwards, the other westwards. Even then, the cable is continuously vibrating like a guitar string, very slowly, but enough to move away from the debris at the right moment. By tensioning the cable or changing the speed on the remaining pods, that movement can be adjusted to avoid the debris. If ejected in a polar direction, the cable and the pod remains would meet only after very many orbits, that is, if the pods don’t slow down due to friction in the atmosphere and burn down before that happens, which is the whole point.

If the linear induction motor works all the way down and the parachutes fail, an extra set of parachutes could be sent up via a small sounding rocket or a weather balloon tethered to the cable. As the pod comes down, it would entangle itself in the tether and pull the parachute out of the rocket or balloon.

An idea that fascinated me was what if that is not enough. I remembered how the catapult of an aircraft carrier is stopped after it has released the plane. The piston runs in a tube which has injectors for water jets that swirl around the inside of the tube. The jets point towards the incoming piston but at an angle so the water remains attached to the tube, being centrifuged by its own speed. The front end of the piston is shaped so it scrapes the water from the tube and sends it back through the center of the tube. The tube is open towards the bow of the aircraft carrier so after every plane departs, the catapult spits a jet of water right behind it.

So, in the case of the ribbon, two water jets could be sent upwards one on each face of the ribbon. The pod would have its front shaped like a snowplow. Scraping the water from the ribbon and sending it sideways or, preferably, back down, would eat up a lot of the speed. Remember that this would only be used if the induction motor did work so the pod would be falling at a few hundred kph, not tens of thousands. At that kind of speed, the pod would not go fast enough to burn in the atmosphere if released. For the final stop, a net can be deployed at the top of Pinnacle or its counterpart in Heaven, like those deployed in aircraft carriers to catch plans whose landing hook is damaged.

I would have loved to put this in the novel but it seemed it would lengthen that chapter too much. It is already dense with technical details, it didn’t need any more.

Eduardo Longoni, a very smart guy I’ve been lucky to work with, was well-known amongst amateur radio operators. When an opportunity came up for them to design and launch an amateur radio relay satellite he was quite excited. I was surprised to find that his main area of interest in that project was heat. I knew heat in space was an issue, but I didn’t quite think it was something to get so excited about.

Perhaps it is thanks to him that I’ve been somewhat careful to explain how pods would deal with heat. After all, any large electrical motor does produce heat, they even have fins to keep them cool. In space, there is no air for a fan to move about. In the space elevator, the electrical motor is part on the pod itself and the other part is the ribbon, were electrical currents are induced, which might warm up dangerously to the point of melting or even burning. After all, any object at such a height above the surface of a planet does have a lot of potential energy and, if you want it to come to rest at the planet surface, all that energy has to go somewhere.

So, that is why I devoted a few sentences to explaining how the heat would be dealt with and how it imposed serious limitations on the speed of the pods.

What I have been not so keen to talk about was about vibration. After all, those long ribbons are like guitar strings ready to be plucked. If vibration gets out of hand, bad things happen, like in the famous Tacoma Narrows bridge, but I admit I don’t know enough to even discuss the subject. My guess is that by carefully spacing the pods, probably not at regular intervals, controlling their acceleration and braking so as not to make stationary waves and adjusting the tension on the cable itself, excessive vibration can be controlled, but I really don’t know that much about that.

The worlds in the novel have very long days, much like our Moon does, about two weeks daylight, two weeks nighttime. Their inhabitants, both man and beast, have adapted to that cycle by hibernating during the night. However, would this be really possible for humans or, in general, for viviparous mammals? It should be Ok for adults but what about babies?

Babies would have to be born early in the day, which should not be much of an issue. When the baby is ready, actual delivery is triggered by hormones and part of the adjustment to the day/night cycle would be to generate those hormones. During their first day babies would need to grow and gain enough weight during that first daylight period to survive their first hibernation. Maternities would have a really hard job early every morning, with all expecting mothers due on that day giving birth to their child almost all at once. The later in the day a baby was born, the less likely he would survive.

Unless, of course, they are neither viviparous nor mammals.

I didn’t think making our characters too alien would add much to the story, thus I made them very, very human. However, I never said they weren’t born from eggs.