WorkInProgress: Deorbital

When we last we left our intrepid crew, they were understandably despondent, as malfunctions — ok, let’s be blunt, an explosion — on their orbital shuttle had left them unable to return to their starship, and essentially doomed to drift endlessly around the alien planet Kepler 62f forever, eventually to die of starvation. Well, forever, or until they run out of fuel for the remaining small thrusters and can no longer dodge out of the way of the abandoned alien space station or its ruined elevator cables to the surface.

But Anna never gives up, and she hits upon a brilliant, if unorthodox, idea that just might save them. But she knows it won’t be popular with Laxmi and Jaci, her remaining crew. Indeed, she thinks it’s crazy herself, but when faced with the choice of certain death or probable death, probable death starts to look rather attractive.

Yes, from the title of this scene, you’ve probably figured out where they’re going next. And come on, you’ve been waiting for this to happen, haven’t you?

So, find out how Anna and crew jump out of the frying pan and right into the fire, with…



header image credit: user:bachstroem /

WorkInProgress: Periapsis

Periapsis: the point of closest approach, or low point, in any orbit…

Anna has finished her EVA repair of the orbital shuttle, and now she, Laxmi, and Jaci are ready to try once again to return to their starship, Aniara. But is the long-abandoned alien space station ready yet to give up its grip on them? Will Anna’s repair withstand the rigors of engine ignition?

Will Jaci stop cracking jokes in the face of imminent demise? We all have our own way of dealing with stress, and this one is his. He really needs to find some little green aliens to talk to, but if that ever happens, you can be sure it will not go as expected.

Periapsis is an orbital component that you might be more familiar with as perigee, and it’s the opposite of apoapsis (or apogee). Perigee and apogee, of course, specifically refer to orbits around Earth (just as perihelion and aphelion refer to orbits around the Sun, and not just any sun, but specifically our Sun), whereas periapsis and apoapsis are “neutral” terms referring to orbit around any central body.

At the start of this scene, the shuttle is in an orbit matching that of the alien station, which is a circular orbit (periapsis = apoapsis) at geostationary altitude and zero inclination (i.e., directly above the planet’s equator). Anna intends to fly the shuttle up to their “parked” starship’s orbit, a hundred kilometers higher, by using a prograde burn to raise their apoapsis to match Aniara’s orbit. Along the way, however, something else happens…

If you want to get into geeky details about orbital mechanics, have a look at my earlier blog post Orbital Mechanics. If you just want to jump right in, however, join Anna and her crew in…


image credit: NASA/JPL-CalTech

WorkInProgress: Geostationary

This scene obviously took me a bit longer to finish than the others before it, as I wrestled with a number of factors. Not least among those was simply figuring out how the crew would go about forcing their way into an alien space station, one that has no direct analog to our technology or knowledge.

That turns out not to be that big of a deal in the end. Is there a hatch on the station? Well, yes, the aliens would have needed a way to get in and out. Ok, so how different can a hatch be? Well, it might be quite a bit smaller, for one thing, if the alien species is quite different in size from humans. But otherwise, it’s still going to be essentially a door, and a door must have some mechanism for opening it.

But… what if the aliens don’t have hands in the way that we do? What if they have claws, instead? Hmm, well, a handle for claws is probably not too different than a handle for hands, assuming those claws can grasp something. And if they can’t, then we don’t have much in the way of tool users in the early history of those aliens, do we?

Do we? Oh, we could go down so many interesting rabbit holes with this one. I think we’ll return to this subject in a later post.

Ok, so there’s a hatchway, possibly a bit of a tight fit, but still a hatchway, and it has a handle. One that’s either frozen with disuse, or locked. Either way, it’s going to need some modicum of force to get in. Applying force, or cutting your way in, in vacuum, in microgravity. What could go wrong?

A lot could go wrong.

The other factor that kept me up late at night doing math puzzles was figuring out what a good parking orbit for Aniara would be relative to the space station. I spent a good part of the last two weeks reading and reading about orbital mechanics and astrodynamics, and my head still spins from some of the math involved. At one point I had myself convinced that, like Zeno’s arrow reaching its target, it was impossible to truly rendezvous in orbit.

Except we do it all the time with the ISS here at Earth.

There’s another post to come on this subject. This one is really quite fascinating to the geek in me.

However, for purposes of this ongoing serial story, there is one factor about Aniara‘s orbit that the careful reader will discern as a departure from the previous scene. In Flip and Burn, you may recall, the Captain, David Benetton, asks our pilot, Anna Laukkonnen, to bring the ship to a parking orbit 100 kilometers north of the station, and to a matching altitude.

However in the scene you’re about to read, Anna does something different. She parks the ship 100 kilometers higher than the station, but directly over it.

Why the change? That, my friends, is going to be the primary subject of my forthcoming post on orbital mechanics. Suffice it to say that after several evenings of scratching about on Excel, I realized that the only way to maintain the same altitude but a different inclination and not smash into the station (twice per orbit, in fact) would be through a fairly constant use of thrusters. This would be an expensive thing to do, in terms of using up not-unlimited propellant, and a responsible pilot wouldn’t do it when a safer alternative that uses far less fuel (or none at all) is readily available.

The risks of pantsing a novel, indeed. That detail in the previous scene will have to change in the rewrite.

Right, so more to come on this subject. Meanwhile, you’re tired of me driveling on about these boring topics, and just want to read a good scene, right? Well, here you go!



image credit: NASA