Archive for Jupiter IV

Jupiter Space

Hubble Space Telescope

We approached the Jupiter System in a fashion similar to the way a ground vehicle pulls alongside another one moving at almost the same speed. The steady pull of the Sun’s gravity slowed the Mission over the course of the 16 month journey from Earth so that we were only moving slightly faster than Jupiter in his 12 year orbit around the Sun. Once in the system, the Mission had to break up into its component parts so each section could use its engines to nudge itself into an orbit around Jove that would bring it to Callisto. We also needed to use a reverse gravity assist to transfer some of our kinetic energy to Jupiter and thereby shed some velocity. I already went though the basic principles of the gravity assist, so if the subject really interests you, look it up for more information.
“Going back to zero gravity soon, Jamie.”
“Suits me, Augie; any change will be welcome. After 16 months, this tin can is getting a little confining. I like all the folks here, or at least most of them, but a few new faces would be welcome.”
“I hear that. This is going to be a complex maneuver. It ought to be pretty spectacular making the close in pass around Jupiter and then spiraling on out to Callisto. We’ll have a great view of Jupiter and the Galilean moons during the whole time. Our hub and the good old Beagle will be gone forever, though. They will just zip past Jove and head into a long solar orbit. We will be in free fall for a few days while we do all this stuff.”

Excerpt Chapter IV: Jupiter Space

Mars

“Not long now, Sam. You folks should be passing over Nicholson’s rim now.”
“Yes, sir! The central mountain is right up in front of us,” I said.
“I think I can make out Schiaparelli!”
Things happened in pretty short order after that. Ranger began
to slow down and lose altitude fast. I could feel the wings changing shape, as well as the small rocket engines of the reaction control system firing intermittently to keep us stable. We seemed to be getting dangerously close to the ground when the nose came up, several control jets fired, Ranger felt like she went into what in aircraft flight terms would be called a stall; then settled onto her belly, at rest.

Eumenides Dorsum

My phone rang, taking me by surprise: “Hello?”
“Hey, Augie! You guys sounded like the crack of doom when you came over. Now my chickens won’t lay for a week.”
“Sorry, Sy. So when did you start keeping chickens? I thought ya’ll were vegans, like the rest of us.”
“Just a figure of speech you literal minded Texan; but you really did rattle the walls. It wasn’t a total surprise though. RT sent us a memo that you were coming over this morning.” Saiyed, his parents and little brother lived at an Atmosphere Project station east of Eumenides Dorsum.

Excerpts from Chapter II: The Long Jump

Photos from Mars Express

Clavius

Illustration from a theater poster for 2001: A Space Odyssey

Jackie put us into a low orbit around Luna that took us right over Clavius and while the protocol and so forth was being settled I got a pretty good view of the place before we actually landed. You could tell the whole thing was bigger and more complex than Schiaparelli and vastly larger than Copernicus; but I didn’t realize just how big it was until I saw it as we were finally coming on approach. I had never seen a man made structure on that scale before: the place was huge. What was doubly unsettling was that this wouldn’t even be a small town on Earth; the Earth that now hung in the sky so close it seemed you should be able to reach out and touch it.

We landed at Clavius within a few hours of sunset so that the shadows cast by the manmade structures clearly contrasted them with the landscape, making them highly visible. Unlike Schiaparelli or Copernicus, Clavius had started as a planned settlement but then went chaotic. The core of the city was laid out like those two, but there the similarity ended. Living quarters, laboratories, garages, greenhouses and other structures were added in what looked to me to be no pattern at all. There were also numerous outlying structures not connected to the main colony, including several privately owned estates and a couple of resort hotels. I had a great view of all of this as we warped into our final approach. Jackie set us down on their landing pad with hardly a bump.

Excerpt from Chapter IX: Clavius

Callisto

So, Callisto has several advantages over the inner three moons, which is why she was picked for the Colony. First, because she is in an orbit almost two million kilometers out from Jupiter, the high energy particles generated in Jove’s magnetosphere that bathe the other three moons are much less intense. That is an important feature because even with our magnetic shielding and all, when we are on the surface, some of that stuff still gets through and can be bad for the DNA. Less is better when it comes to radiation. Second, Callisto is geologically pretty quiet when compared to the others. The tidal forces generated by Jupiter’s powerful gravity field are not present in sufficient strength to cause internal heating of the type found in varying degrees inside the other moons. Without the heat, there are no volcanoes, or tectonic activity to cause earthquakes. Callisto had about as much geological action as Earth’s moon, which is not much. Third, the old girl had water and lots of it. There was ice scattered around on the surface, permafrost below the surface and an underground ocean about 50 kilometers down that was like something out of Jules Verne. Of course water gave us what we needed for the fuel cells, allowed us to make propellants for the point to point rockets we used for our exploration of Callisto and when distilled, provided many valuable minerals and salts.

Excerpt from Chapter IV: Jupiter Space

Newton’s Cannon

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The Oberth Effect

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Track of the Galileo Mission

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Down the Cable

Each propulsion module was equipped with the main cable on which hung the habitat and the solar panels arrayed along its length. Each spoke of the pinwheel also had a smaller cable that ran alongside the propulsion module, then paralleled the main cable and attached to the side of the habitat, next to the airlock. This was the cable on which we were to move until we landed on the small platform jutting out from the airlock. The plan was to hook onto the cable with a braking mechanism that was in turn hooked to our strong safety belts. Then we would move hand-over-hand down or up the cable, depending on how you looked at it, until there was enough centrifugal force to pull us along the cable, at which point the brake would allow us to move in a controlled manner. Simple.

I made my way to the small personnel cable, hooked on, and started my trip. But despite my best efforts to keep my eyes focused on the job right in front of my nose, my attention repeatedly strayed to the greater space around me. The sensation of weight increased as I moved along the cable, and with it the dizziness induced by our circular motion. Two revolutions per minute would not cause dizziness for those inside an enclosed habitat because they only feel the sensation of gravity the rotation creates through centrifugal force. We, on the other hand, were outside watching the sun, stars, and planets whirl by like the spectators one would see while riding an Earth-side amusement park ride. I got sick to my stomach. Fortunately, or rather as a result of Captain Jones’ foresight, none of us had eaten for hours prior to the EVA so the nausea had no disastrous results.

According to the plan, we were to use the brake when we neared the habitats and gently lower ourselves to the platform. Well, the brakes were not nearly sensitive enough for the lightness of our bodies. They either stopped us cold when engaged or allowed us to fall freely when disengaged, so we ended up dragging ourselves the rest of the way to the habitat airlocks with the brakes on. It was slow and exhausting but had the unintended positive effect of taking my mind off the universe whirling around me. I was glad when I was inside the airlock with the door closed, watching the indicator lights as it cycled. I’m no agorophobe, but the feeling of spaciousness outside was just a little too much for me.

Excerpt from Chapter II: Galileo Mission

Artwork by Joe Hardwick

Copernicus to Clavius

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Glossary

Aldrin Cycler: A large habitat traveling in a permanent orbit around the sun that crosses the orbits of Earth and Mars every 26 months. It is used as a “space hotel” for colonists on their way to Mars, both reducing time in transit, while increasing comfort and safety. It is named after its original inventor, twentieth century Lunar astronaut, Buzz Aldrin.

EVA: Shorthand for “Extra Vehicular Activity”, a term coined in the earliest days of human space flight that has lasted to the present day and is now used to describe whenever one goes outside a pressurized habitat.

Regolith: Term that describes the rocks and other inorganic material that make up the surface layer of some planets and moons.

Sol: One full rotational period of Mars or one Mars day. It is 24 hours 39 minutes in duration when measured in standard Earth time units.

Specific impulse: A term applying to the amount of propulsive energy generated by a rocket engine. The greater the specific impulse generated the more kinetic energy that can be imparted to a rocket and its payload.

Verniers: Small rocket engines located at strategic points on a spacecraft that are used to change its orientation or attitude relative to its direction of motion.

WC: Short for “Water Closet.” This is an old term, once widely used and recognized in Europe, referring to a restroom or bathroom. It fell into disuse during the late twentieth century and then re-emerged and came into common use again among Mars and Lunar colonists, many of whom had European backgrounds.