Periods of rotation for Io and Calisto
Periods of orbit for Io and Caalisto
Size (in km) of orbital paths for Io and Caalisto
Distance between the orbital paths of Io and Caalisto
What moons lie between Io and Calisto? Their orbital periods?
Is it necessary to travel only in the orbital plane, or could one go, as it were, above or below the orbital paths of intervening moons?
Do intervening moons have sufficient gravity to use any or all for gravity assist, depending on the distance between Io's and Calisto's orbital paths? Would this be necessary or desirable?
How would Io station and Calisto Station communicate? Radio, microwave transmission? Other forms of transmission?
What would the delay time be? Are the orbits far enough apart and large enough that the delay time would vary? What about when the two moons were on opposite sides of Jupiter?
When Io and Calisto are occulted with respect to each other, could transmission relays on other moons/space stations in Jovian orbit maintain uninterrupted communications?
Is it possible that delay times would be low enough to allow "normal" conversation between someone on IO Station and someone on Calisto Station, or someone in low orbit around Io and someone on Calisto?
What is the delay time from Io to Earth?
How long would it take for a two seater, Ferrari-type spacecraft to get from Calisto to Io? How large would the differentials be with regard to relative orbital positions? Minutes? Hours? Days?
Io, 1.77 days, 422,000 km
Europa, 3.55 days, 671,000 km
Ganymede, 7.15 days, 1,070,000 km
Callisto, 16.69 days, 1,883,000 km
Thus the distance varies from 1,411,000 km to 2,255,000 km or 5 to 7.5 light
seconds. Round trip time, for answer to statement, varies from 10 to 15
seconds, uncomfortable but manageable for a conversation. Io zips around
Jupiter so quickly that every second day there might be a period of ten
minutes during which communication is impossible. The two intermediate moons
might block communications for a few minutes every so often, but this would
be only a brief inconvenience.
Frank was dead; and, I knew who murdered him. Not the name of the person who had tampered with his suit so cleverly that no one except me so much as suspected that his blocked air feed was anything other than a tragic accident caused by human error, his own error. But, I knew whom his findings would damage and who, for that reason, had wanted him dead as soon as their spies discovered why he was really on Io Station, and whom he was really working for.
As for me, I could only trust that they didn't know he had given me the information. It was a pretty thin thread to hang a life on; and, if it weren't for the vital importance of that information and, more important by far to me, Frank's urgent appeal that I get it to the admiral, I wouldn't have cared about any threads. My Frank was dead, and without him I couldn't bear to go on living. But, he'd given me a job to do. If they murdered me once it was finished, that was okay by me. But, right now, I had to make them believe I was harmless.
That wasn't, actually, very difficult. The other crewmembers had never taken me seriously. A poet on Io Station? They all assumed, in their smug, insular fashion, that I couldn't be the chief engineer's intellectual equal. Their patronizing attitude towards me had infuriated him and hurt me. After all, our friends back in Green Belt understood that, though my Master's was in Creative Writing and my poetry had achieved a certain amount of success, including a Reisling Award, I was also an amateur cosmologist, well able to follow the broad outlines of planetary science and even some of the finer detail. Frank Lange was a planetary engineer, for Pete's sake! He wouldn't have married some nitwit who didn't know an asteroid from her ass. But, that was exactly what, to a person, the crew of the Io station thought I was.
Frank had come home fuming about three standard weeks after we arrived. "Do you know what that lousy SOB Stafford had the unmitigated gall to ask me?" he demanded, suit jacket forgotten, in one hand and dragging on the floor.
Stafford didn't concern me; but Frank's blood pressure did. So, I calmed him and settled him with a cold Coke before asking as blandly as possible, "So, what did Stafford ask you?"
Frank spluttered. "He asked me what we find to talk about. He asked me why I hadn't married someone more suitable. More suitable! Can you believe it? As if there's something wrong with me because my wife isn't a physicist, or astro-biologist, or whatever his timid little mouse of a wife is." He took a long, cooling drink.
"I am the only spouse who isn't a scientist, practicing or otherwise," I pointed out. "Have some soy pasta chips." He munched them absently. "Then too," I continued, reaching for a chip, "You - well, and I - seem to be the only people on the station who realize there's a world beyond NASA. We've been in the Greens' quarters, and the Kowalski's. Do you remember seeing one volume of Dickens, or Dovstoievski, or Cardinal Newman? Or even SF: McCaffrey or Le Guin or Kim Stanley Robinson? And no poetry, no history, no reading matter at all but technical monographs and journals." Frank agreed thoughtfully and got up to refill our glasses. "And, do you remember what Joanna Kowalski said when she saw all our books and CD's?"
His eyes flashed. "Yes," he growled. "She asked me why I had let you bring so much extra weight. 'After all, you're only going to be here three Earth years. She could have left all that junk in storage' Junk! Elliot Gould playing Bach and G.K. Chesterton are not junk! And so I informed her. But, she just gave me a pitying, condescending look, as though I were some besotted old fool."
"Well," I said mischievously, "you're not old, anyway." It took a moment, but he had laughed. And, it was that evening that we realized that we might turn their attitude to our advantage. As long as they thought I didn't understand his day-to-day work; then, if they discovered his true work, they certainly wouldn't think I could understand that. And therein lay hope. For I could channel information to Admiral Sing, or at least to my Brother, Stacy, who was his aid, without attracting suspicion or even attention.
It was soon after that that frank came up with the idea for the bracelet. It was a cheesy idea, which is why it appealed to us both. It was so totally brainless that no one would ever suspect its true purpose. Once in Greenbelt, while in bed with the flu and too weak and miserable even to read, I had paused my channel surfing on the Jewelry Channel to watch a demonstration of make-it-yourself jewelry in which you take an empty setting, of a pendent say, select the gem stone you wan too mount, and just snap it in. I'd told Frank about it, and we'd had a good laugh. But, I'd begun to think about it. Would it be possible to de-mount the stone if you got tired of it? And, did it have to be only one stone? To my amusement, Frank had become so intrigued that he actually bought a jewelry making kit. It included a bracelet. We'd never been bored enough to mount stones in the bracelet, but now he suggested that he could mount his data crystals in it. We'd give out that we'd decided to mount one stone for every month of our tour. Frank took it as a good omen that the bracelet contained mountings for thirty-six crystals. Since our colleagues on the station already thought me silly and eccentric, the bracelet caused little interest.
Frank had to work quickly, but undetected. If he was right, the Io station had a little more than half those thirty-six months. A previous whistle blower had been silenced by being thrown out of a helicopter without a parachute. Things like that happened to people who criticized the President's brother's construction company. That company had, surprise, surprise, been awarded a no-bid contract to build the Io station. And, if what Frank and his friends suspected was true, the failure would make Morton Thyicol's failure with Challenger's O rings and the failure of Columbia's heat shielding tiles look like church picnics.
Seventy people lived and worked in Io's habitat, a habitat which was built not on but in Haemus Mons. Admitedly, this mountain near the South Poll was not volcanic, to the best of our knowledge. Nonetheless Io, third out of Jupiter's satellites, orbited close enough to the giant planet to experience, among other things, tidal action and consequent internal heating so severe as to make this little world, barely larger than Luna, the most volcanic body in the known Solar System. Such atmosphere as it had was mostly sulfur dioxide, and the mean surface temperature was -143°C. I'd never bothered figuring out what that came to in Fahrenheit. It was undoubtedly below the survivable range for humans. And, if the unbreathable air or the cold didn't get you, Jupiter's radiation would. And yet, even a "minor" failure of the station's superstructure or systems would send seventy shirt sleeved or pajamad residents rushing for the space suit lockers.
We weren't allowed to keep our suits in our quarters. "Contamination," Rothstein had explained, the miasma of contempt thickening almost visibly with each syllable. "We can't risk contaminating Io with any, anything from our habitat, and we can't risk contaminating the hab, uh, habitat with anything from out on Io. So, everybody and every suit is thoroughly decontam, cleaned before going out and after coming back."
Bristling at his "I'm talking to a retarded three-year-old" tone, I managed to keep my own tone light and conversational. "Yes, I understand that. But, what if there's an emergency?" Rothstein glared. "Some sort of breach or failure of the hab in which we'd need to suit up fast?"
"Obviously, Mrs. Lange," he said, leaning all his considerable weight on the Mrs., "you don't understand anything about the construction or management of this station." He turned away. "There are failsafes, backup systems…." He glanced over his shoulder, his sneer almost a snarl. "Nothing on this station can fail." Not till we were settled in and Frank had a chance to run unofficial background checks on the station personnel, about the beginning of our second week, did we discover that Chief of Security Robert Roghstein was one of some half dozen crew members employed by both NASA and ConStel (Construction Stellar International Inc.)
But, if my hunch was right, not even the sneaking, spying, eternally damnable bastard who killed my Frank knew that I understood the nature of Io, much less the nature of Io Station and the terrible danger it was in. Naturally, if I didn't know what Frank had been working on, I didn't pose any threat to them. But, just in case, I had to play the shattered widow to the hilt; the devoted wife so devastated by her loss as to be worthless from the standpoint of intelligence gathering. It was an easy roll too play, not a roll at all, really. I was shattered. I was devastated. The only thing that kept me from losing my mind altogether was the ingrained memory of what Frank had told me every morning before he left for work, every night before he went to sleep, and on the rare occasions that he left the station. He'd always said two things: "Remember, if something happens to me, Jill, get the information to Sing. And, remember that I love you."
Now, as I stood, suited and helmeted at the small port beside the outer lock of the Prometheus, one of Io Station's two shuttles, I remembered our last kiss before he'd gone in to suit up for the unexpected EVA. He'd gone through his little spiel as usual and, as usual, I'd said, "I'll remember. I love you, darling."
Then he said:
"One kiss, my bonny sweetheart, I'm after a prize tonight,
But I shall be back with the yellow gold before the morning light;
Yet, if they press me sharply, and harry me through the day,
Then look for me by moonlight, watch for me by moonlight,
I'll come to thee by moonlight, though Hell should bar the way."
And he'd kissed me again, holding my shoulders in his big, strong, gentle hands. And then, without a backwards glance, he'd strode into the suiting up chamber. I'd stood still for a moment, looking at the closed door, before making my way back to our quarters with an uneasy feeling firming into certainty about the significance of those lines from "The Highwayman."
I'd called Stacy, insisting a little hysterically on a super secure line, and told him. "So," he said, speaking slowly to reduce the stutter that excitement or anxiety always brought on," you think King George's m-men will come m-marching, or already have?
"Yes. The more I think of it, the more certain I am that he's been compromised or caught outright." I swallowed. "Stace, I don't think he'll come back."
Stacy was silent for a long moment. Then he said even more slowly and deliberately, "I think, I think you're in for a very rough time, Jill. Remember what Frank told you - _everything_ he told you!" As I started to reply he broke in firmly. "Sorry, Sis, gotta go. Talk to ya soon. Love ya." With that, he'd broken the connection, leaving me to speculate miserably about his safety as well.
About four hours later Rachel Green, Director of Io Station, had called me to her office and told me, as gently as possible, that Frank wouldn't be coming back. She'd been very kind, had made all the arrangements with NASA, and had brought me up on the Prometheus for the burial in space. So now I stood in the air lock with Director Green, Deputy Director Ivanov, Roger Roberts, Prometheus' pilot, and the body bag wrapped in the American Flag that contained the mortal remains of my husband. I had asked, at some point, to see him; but Director Green had told me gently but finally that it would be better for me not to. And, I hadn't asked again.
"Taps" was playing over the com. I switched my com off. "Taps" made me cry under the best of circumstances. And these were not the best of circumstances. I blinked and clenched my teeth. The outer hatch opened, and I watched through the port as the flag-wound body bag shot out of the lock and floated amid the stars.
"They couldn't even give him a casket," I thought bitterly. Startled, I realized this was the first coherent thought I'd had in hours. Then there came into my mind the lovely lines Robert Heinlein wrote to be sung to the Navy Hymn:
Almighty Ruler of the all,
Whose Power extends to great and small,
Who guides the stars with steadfast law,
Whose least creation fills with awe,
O grant thy mercy and thy grace,
To those who venture into space.
I whispered the words as the slight shuddering of the wall beneath my hand signified the closing of the hatch. After what seemed like a long time, I felt a touch on my arm. Without switching on my com, I turned and followed Director Green inside.
My fingers were clumsy, and the simple act of popping my helmet seemed to take long minutes. As soon as it was finally off I said, more querulously than I intended, "I want to go to Calisto, to Stacy."
Rachel paused in the act of stepping out of her suit trousers, and looked at me compassionately. "Of course, Jill. Demetri and I have to get back to the station; but, I can have Roger fly you over. I'm sure he wouldn't mind under the circumstances."
"Sure wouldn't," Roger said. Glancing at him, I saw the slight, milk chocolate complected pilot, already unsuited and stowing his gear, pass the back of his hand across his wet cheeks. He was young, on his first off-Earth posting, and Frank had befriended him.
Watching him as he closed the locker and eagerly turned towards me, it struck me that we were the only friends he had on Io. Yet, I couldn't even trust dear Roger. For all I knew, he had killed Frank and would kill me, or take me to ConStell headquarters to be tortured… I couldn't trust anyone from Io. I had to get away from all of them.
"No," I wailed, feeling the hysteria finally rising as inexorably as Prometheus' lava. "I want Stacy to come get me." Dropping my gloves on the floor, I sank my head into my hands and burst into tears.
I was vaguely aware of Rachel speaking quietly with Roger. Then, after a few moments, I felt Demetri's arm about me. He was a big man, almost as tall as Frank, and he supported me effortlessly. "I understand," he said in his rumbling, heavily accented English. "Everything and everyone associated with Io Station is repugnant to you now. You want only to see your brother, not even to stay on the Prometheus any longer than you can help." I could only nod against his shoulder. "Of course. We understand. Let us help you out of your suit, and you can go call him."
Like a child, I stood still as they quickly and efficiently unsuited me. As soon as my arms were free, I touched my right hand to the bracelet on my left wrist. It held eight crystals. Frank had mounted the eighth the night before he, he was lost. Since the stones were ostensibly to mark each completed month of our posting, Frank had mounted each on the last day of the month. So, it was now October Second, about twenty-four hours since he had gone away. October Second. Something stirred in the back of my mind, but I was too distraught to grasp it and it fluttered down into oblivion again.
By the time I spoke to Stacy, he and a hanger crew were already going through final check outs on the Galactica, his personal, two-passenger space plane. "Your friend Roger called and told me you needed me to come get you," he said; and, I was so distraught that this didn't strike me as odd.
Frank had suggested we drive out to the beach. Though, loving the Maine coast in all seasons and weathers as I did, I gladly agreed, it did puzzle me that he, not a beach person even in August, would make the suggestion. But, at his troubled look, I suddenly remembered what this all too rare holiday had, briefly, allowed me to put out of my mind. In a few short weeks, we would move in as part of the inaugural crew of Io Station. The quaint inn where we were staying seemed ordinary and safe enough. But, as Frank said, "I'm not paranoid if someone really is trying to kill me."
We drove with little conversation. Leaving the car in the otherwise deserted parking lot, we trudged across the dunes and the wide stretch of sand, sepia under the cloudy sky, to walk on the firm sand at the water's edge. We took our time. And I thought, not of the deep, soft sand under my boots nor of the salt-laden wind, soft as a June breeze, that brushed my face, but of the world we would soon call home.
I'd visited space and research centers on Tarra. The day at Kennedy Space Center my bemused parents had given me for my tenth birthday remained in my memory as one of the chief occurrences of my life. Less than two months later, the Delta 5 rocket carrying the first payload of nuclear waste being shot towards the Oort Cloud had exploded on the launch pad, destroying a large part of the Southeastern U.S. Later, I'd visited ESA and CSA facilities with Frank and, had toured the Cosmodrome at Vaikanor with almost as much excitement and enthusiasm as the Cape itself. We'd travled to the International Space Station, the Lunar Tri-Cities of Armstrong, Collins, and Aldren, and the Martian city states of Lewis, Bradbury, and Burroughs. And, of course, I was familiar with Calisto and Ganymede Stations. But, I'd never seen anything like Io.
The station had been built, ostensibly, as a research center. But, that cover story had never made sense to me. The research center an Ganymede was generously sized and amply equipped. It was operated by ESA, sure, but parochial considerations of what tarran flag an off-Tarran base or colony nominally had been established under meant little to most people and less to space scientists nowadays. Any research NASA wanted to pursue could easily have been accommodated at Ganymede. Of course, ConStel had lost the contract on Ganymede, unfairly as th CEO had screamed across the media like a toddler whose favorite stuffed toy had been taken away, to British, French, and Icelandic companies. Since Pres. Arthur A. Chester had, to his astonishment and chagrin, been unable to bully and threaten ESA, the EU, the UN and the international Space Consortium into nullifying the contracts and awarding the entire project to ConStel, he had arranged Io as a consolation prize for his baby brother's firm. That was an open secret in the space community. But, it didn't answer the question of why Io? What did this volcanic little satellite have that ConStel or anyone else could possibly want?
As we strolled, looking out to the grey expanse of the Atlantic, I put this question to Frank. He paused and looked at me with a mischievous, almost a boyish grin, which slowly faded to his now accustomed expression of vague worry. "They've found a life form," he said, "a microbe, on Io. An extremoophile that actually feeds on radioactivity, breaking it down into harmless chemical compounds."
I stared, momentarily speechless. "The first extraterrestrial life," I breathed. "Frank, it exists! We're not alone!" I drew a long, shuddering breath. "Microbes on another planet, well, satellite. They should name them Saganoids, or something."
Frank smiled sadly. "Yes, they should. I doubt they will, though." He glanced around nervously. The bleakly beautiful beach was deserted; not unusually for Castene Maine in mid December. "This is highly classified material, known only to a very few outside the NASA and DOD highest circles."
I frowned. "but, surely, such a discovery is the story of the century, of the millennium. We've finally found ET. What's more, ET can do something of tremendous service to Tarra…" I paused, a chill running through me. Just about every plant, animal, and chemical compound that might conceivably be of use to Man had long ago been patented by the pharma-chem-ag mega-corps. "They're going to patent the Saganoids?" I said, but it wasn't a question.
Frank nodded. "But, that's not the half of it."
I shuddered again. "What could be worse than that?"
"Lots of things," he said grimly. Sen. Harper and Admiral Sing think a fundamental design flaw in the station on Io was glossed over, covered up." I gulped, a chill sweeping through me that owed nothing to the large, fluffy snowflakes floating on sea breeze. He scuffed the sand with his boot toe. "Best estimates are," he said quietly, "that the habitable part of the station, which is the important part, after all, will fail about eighteen to twenty-four months after completion. Although the station is built in one of the few relatively stable parts of the world, it's still mainly underground and the tidal flexing will eventually breech its integrity, not because such a breech is inevitable, but because of the methods and materials used in its construction, in combination with an inadequate design." He sighed. "With only one of those problems, even the poor design, the danger would be far less immediate. With all three…" He waved his hand.
He laughed humorlessly at my shock. "What do you expect? Constel uses its own designers, engineers and architects. They use their own proprietary methods and materials. What else would they use? And, their inspectors approve every bolt and man hour. We can't have OSHA, or the Mine Safety Administration or any other government body, not even NASA, unduly interfering with their business, now can we? And, hey, it's good enough for government work. Who cares how many people are killed in the eventual structural failure? It won't disturb Constel's bottom line."