Comet! Read online

  Chapter Nine

  As they carried the scope and port energizer out to the parking lot Emma said, “You know, I’ve been thinking about it. We could send a mission to Alpha Centauri after all. I mean, without going to Australia which, I must say, would be an awesome way to do it.”

  Distractedly Ell said, “We could?”

  “Yeah, I’ll bet once you line your scope up on a couple of known Northern Hemisphere stars you could tell its AI to point it at Alpha Centauri even though the earth’s in the way.”

  Ell paused, focused far away, “Oh, then we just open up a port about three light years out and see if we can see ‘Alpha C’ in the port? Adjust the direction based on that?”

  “Yep. I don’t know what you have in mind for tonight, but could we send a port that way first?”

  “We’d want to send two ports.”

  “Two?”

  “Alpha Centauri is a binary star. Alpha Centauri A and Alpha Centauri B. Both of them are fairly similar to the sun and the planetary searches have shown evidence of planets around both of them. The planets’ orbits probably aren’t terribly stable in a binary system though.” Ell paused, “Well, maybe one port would be enough. From one port we could check both stars for habitable zone planets. Then send a mission to whichever planets looked interesting.”

  “OK, let’s do it!”

  “First we’ve got to do a little comet hunting.”

  “Comet? I thought the ET Resources guys were exploring our solar system?” She drew herself up and put a hand on her chest, “We’re exploring stars.”

  “Em?”

  Emma turned to look at Ell, hearing stress in her voice, “Yeah Ell?”

  “I got a call today from Wilson Daster, one of the discoverers of comet Hearth-Daster.”

  “The one they were making jokes about? ‘Earth-Disaster’?”

  “Yeah,” Ell said somberly, “According to his figures there’s a 4 to 25% chance it will actually hit us.”

  Emma leaned on her rolling table a second, then slowly sank to sit on the ground. “Oh Christ,” she said, barely audible. She lay back on the ground, “Shit! I can’t feel my finger tips.” She wiggled her fingers.

  “Slow deep breaths.”

  “How big is it?”

  “300 million metric tons.”

  “Oh my God! How much kinetic energy is that?”

  “129,000 megatons of TNT.”

  In a whisper, “Jesus!” Emma rolled to her side and curled up into a ball, arms around her knees.

  Ell sat down beside her and uncertainly patted Emma’s shoulder. “Slow your breathing girl.” She lay down behind her and reached an arm over and around, hugging her friend, “Slow down… relax.”

  They lay that way for a few minutes. Finally Emma shuddered, then turned her head a little. With a desperate little chuckle she said, “So we’re gonna launch a little rocket at it?”

  Ell could see the unshed tears gleaming in her friend’s eyes. She shrugged, “Yeah, well, first we’ve got to get more information. We need to know its exact course, so it would help to have a rocket with ports tracking it. By tracking it we can refine its course and watch for outgassing events as it approaches the Sun. Outgassings might change its course. We’ll be able to send prospecting rockets through the ports to sample and determine its composition. We could make some attempts to deflect it.”

  Emma pushed up onto an elbow. “OK,” she said sluggishly, “Let me call my folks first.”

  “Emma! If you start telling people and word gets out, the panic alone could kill millions! Do not even dream of calling anyone! I wouldn’t have told you except that I can’t do this stuff alone.”

  “Just my family!” Emma said doggedly.

  “Just no one! Every person you tell will have just a few other people they feel they have to tell! Don’t panic yourself. Help me figure out if there is anything we can do to save the planet! Don’t get selfish people buying guns and turning themselves into ‘survivalists.’”

  Emma shook Ell’s hand off her shoulder, “Don’t tell me…” She shuddered again and drew a deep breath. She held it a while, then drew another. Quietly she said, “Sorry Ell… You’re right. Give me another minute and I’ll be ready to help.”

  Ell patted her shoulder uncertainly, wondering if she should sit with Emma a while longer. She decided that action was the best medicine for anxiety and so thumped Emma’s shoulder with more confidence. “Good to hear. I’m going to get started. Let me know when you’re ready to help.”

  Before Ell had completely zeroed in on the comet Emma had gotten up and calibrated her energizer. In about twenty minutes they had popped out a port near the comet and were heading back inside the building to send a bigger port. Once they’d done that, they sent Ell’s new rocket with ports and the laser rangefinder through to the comet.

  Once they had the comet up on their screens they could see the central nucleus slowly tumbling. The image was a little foggy because of the gasses streaming out of the comet even though those gasses weren’t visible yet through their ground based telescope.

  “Allan, are you getting good signals from the video cameras and laser?”

  “Yes.”

  “Please exactly match course with the comet using the laser rangefinder, then begin plotting its course as accurately as possible to refine its orbital trajectory and recalculate the likelihood that it will strike Earth.”

  “Understood.”

  Emma said, “GPS won’t work out there, how is your AI going to know where that rocket is?”

  “Take the video images from the forward and four peripheral cameras and identify known stars and their angular locations from each of the images. Those kinds of calculations are hard for us but trivial for a supercomputer.”

  Emma’s eyes lost focus a moment, “Oh yeah, I can see that now. When will we know more about the likelihood of Earth impact?”

  “Allan?”

  In Ell’s ear Allan said, “The longer the baseline the more accurate the projection. But we should be able to surpass the accuracy of Daster’s projection by morning.”

  Ell turned to Emma, “Morning.”

  ***

  When Ell got down to the kitchen in the morning she found Bridget already there, making omelets. “Hi Bridget. How are you doing?”

  “I’m doing fine, thanks to you and Emma. Hope you like omelets. Wow, you work long hours!” she said concernedly, “I stayed up until midnight last night waiting to see you and say thanks.” She frowned, “Or did you go out?”

  “No, something big has come up at work. Is there anything I can do for you?”

  “Oh, no! You’ve done so much already. I just wanted to tell you I’ve found a sublet and will be able to move out today.” She served Ell an omelet.

  Ell’s eyes narrowed, “What about Sam?” She shoveled up some omelet.

  “He’s still in the hospital. They did a long surgery on his hand. Your barbecue bottle really busted it up. When he’s discharged he’ll go to jail until he can make bail.”

  Ell eyed her omelet, “These are good… Aren’t you worried that Sam’ll come after you once he’s made bail?”

  Bridget shrugged, “His hand’s messed up enough that he’d have a lot of trouble trying to physically hurt me. The police assure me he won’t be able to legally buy another gun.”

  “What about illegally?”

  Bridget frowned, “Well, yeah. That’s a problem.”

  “You know him; do you think he’s the kind that might?”

  She sighed, “He holds grudges forever.”

  “Are you in school or working?”

  “I worked as an admin assistant at the University but Sam made me quit.”

  Ell frowned, “Why?”

  “He said because he could support us and he didn’t want me to work. But I think he was jealous of my boss.”

  “Can I have another omelet? Your boss was a man?”

  Bridget’s eyes widened at how fast the first omelet ha
d disappeared. “Well I worked for six professors, but one of them was young and handsome and Sam almost went crazy after he met him at the office Christmas party.”

  “Do you have another job yet?”

  “No, but I’ll get one.”

  “We probably need a good admin out at Quantum Research, where I work. It’s guarded so that Sam couldn’t come into the building. You could stay with me a while longer too. Rent free and there are good intruder alarms in this old farmhouse.”

  Bridget stared at Ell wide eyed. “I could pay some rent.”

  Ell grinned at her, “You could make me omelets every morning.”

  Bridget grinned back, “Now you’re asking a lot. I don’t usually get up this early. She wrinkled her nose, I guess I could make an exception for the woman that saved my life though.”

  “Well, eat your omelet and let’s go talk to Sheila at Quantum Research, see if they’ve got a job for you.”

  ***

  Ell walked Bridget down to Sheila’s office. “Hi Sheila. This is Bridget. I called you about her earlier. Hoping we have an admin opening?” She winked at Sheila with the eye that Bridget couldn’t see. She hoped she wasn’t overdoing her efforts to make it seem she wasn’t actually in charge.

  Sheila said, “Um, yes I checked and we are authorized for another admin position. Let me just talk to her and I’ll get her to Nancy from HR.”

  Ell turned to Bridget, “If it doesn’t work out, my car can take you home and come back for me later. Good luck.”

  As Ell walked down the hall to the machine shop she said, “Allan, what’s your projection for Hearth-Daster?”

  “The likelihood that we’ll be struck by the entire comet is low, on the order of 5-15%…”

  Ell felt some relief.

  “…because it is likely that the major fragments visible in the core will separate during the comet’s perihelion with the sun. The likelihood that one or more of the fragments will hit is high, on the order of 50-75%.”

  Ell’s shoulders sagged, “And the energy delivered by a fragment massing one fifth of the total comet?”

  “23,770 megatons of TNT.”

  Ell reflected that one or two impacts that size might not cause the extinction of the human race, but that that would likely be of little consolation to the billions of dead. After standing stock still, staring into space and considering for a moment or two longer she turned toward the area of the D5R building where the ET Resources group had set up.

  Braun was by himself at a work station, “Bob, can you let me look at those five kilogram impactor rockets you’ve been using to turn your asteroid into rubble?”

  Getting up from his workstation, Braun said, “Sure, we’ve got a couple over here. They’re about as simple as it gets. A big chunk of cheap steel at the front to give it mass. There’s a camera at the front and a PGR chip that sends the video home. The steel impactor is just screwed on to the pusher assembly at the back. It has three attitude jets, three more cameras and a main rocket. All the calculations and controller adjustments are done using computing resources and valves back here at ETR. When you suggested we reuse them we realized all we had to do was put a little motor on the screw that holds the steel impactor to the pusher assembly.”

  “The Quantum Research group needs a few of these ASAP. Can we bum a couple of yours?”

  He frowned, “They don’t take long to make.”

  “Great,” Ell grinned at him, “then you won’t suffer much, not having them until you can make more. This is important.” Ell paused a moment, “We’ve got something for you in return.”

  Eyes narrowed, Braun lifted his chin for her to continue.

  Ell told him about the one ended ports and her offer to place transfer ports near locations of interest around the Solar System. His eyes widened further and further during her description.

  “My God! That’s fantastic! Can we shoot a transfer port out to the asteroid tonight?”

  Ell frowned, “You don’t already have one there? You’ve already sent missions there, haven’t you?”

  “We uh…” Braun looked sheepish, “we didn’t think of sending a port out there just so we could put later missions through it.”

  Ell grinned at him, “My daddy used to say, ‘Gotta be smarter than the tools you’re using.’”

  Braun drew himself up and placed his hand on his chest, “Hey, I am a rocket scientist you know.” His shoulders slumped, “Apparently, just not a very smart one.”

  Ell said, twinkle in her eye, “Perhaps then you haven’t considered that you could put a port into Earth orbit so you don’t have to launch little rockets from the parking lot anymore either?”

  Braun actually blushed, then grinned, “Sure, you can have some of our five kilogram impactor rockets. Not a problem. Take as many as you need. Us dummys’ll make more.”

  Back in the Quantum Research area Ell found Emma and Roger. Ell had asked Emma to swear Roger to secrecy, then fill him in on the comet problem. Roger looked pale. Ell set the 5 kilo impactor rocket down in front of them. “Time to start looking into whether we can move that comet or not.”

  Roger looked up at Ell, “Holy crap, Ell!”

  Ell put her hand on his and quietly said, “Yeah, I know. This is about as ‘holy crap’ as it gets.”

  Emma was staring off into space as if considering something.

  Roger said, “When Emma swore me to secrecy, I had no idea what I was swearing to. I’m not sure this is something that should be kept a secret!”

  Ell sat with him a while, explaining her concern that public panic might cause immeasurable harm whether or not the comet hit. Just as Ell seemed to have convinced Roger, Emma pulled her focus back from wherever it had been and looked at the rocket. “What’s this?”

  “It’s a five kilogram rocket that essentially consists only of a guidance package, a thruster and a chunk of steel to provide kinetic energy. The ET Resource guys have been using them to bust up their asteroid in prep for mining it.”

  Emma’s eyes narrowed. “This couldn’t possibly bust up that comet!”

  “Well no. But they’re flying these into their asteroid at 22 kilometers per second. Five kilos at that speed delivers the kinetic energy equivalent of 290 kilograms of TNT.”

  “Ell, I thought you said the comet masses 300 million metric tons?”

  Ell shrugged, “Probably. It has a diameter of just under a kilometer and, if its density is somewhere around the 0.6 gm/cm3 estimated for comets, then it will come in at close to 300 megatons.”

  Emma shook her head, “Like I said, this isn’t going to bust up that comet. It’d be like using a flyswatter on a blue whale!”

  “Oh, no. It couldn’t bust it up. But it should transfer that kinetic energy to the comet and move it a little.”

  Emma’s eyes widened. In the tone you use speaking to a child she said, “The energy from 290 kilos of TNT isn’t going to move 300 megatons very much either Ell.”

  “Well, no. It would move it at a rate of…” Ell’s eyes defocused a moment, “two tenths of a mile per hour.” Her eyes refocused on Emma, “Which isn’t enough admittedly, but remember we can build ones that will hit at 150 kilometers per second instead of the 22 kps this one will go. That will deliver the energy of thirteen and a half tons of TNT. With one of those we can move the comet…” she defocused again, “2.2 kilometers per hour.”

  Wide eyed Roger said, “The earth is a target 12,000 kilometers wide!”

  “Yeah, at 2.2 kph it would take eight plus months to move it the 12,000 kilometers of Earth’s diameter and we’ve got less than 4 months. But, we can hit it more than once you know?”

  Emma’s eyes defocused again.

  Ell said, “I was thinking along the lines of a 25 kilo rocket at 150 kps for 67 tons TNT equivalent. That would move our comet at almost 5 kilometers per hour. At that rate it would take a hundred days to move the comet an Earth diameter. Admittedly, we’d want to move it a lot farther than one Earth diameter but we could
just keep shooting at it until we were happy.”

  Emma’s eyes narrowed, “What if you break it up into ‘cosmic buckshot’?”

  “Yeah, that’s a problem. So, first we hit it with this little five kilo rocket at 22 kps and watch to make sure we aren’t breaking it up. Then we gradually increase the power of our strikes, checking the stability of the comet after each one.” Ell put up a finger, “Sorry, I’ve got a call I need to take.”

  Emma’s eyes defocused as Ell wandered away. Roger pulled over a screen to start running some numbers of his own.

  Ell said, “Wilson, how are you? What did your wife say?”

  “I’m OK. Taking a lot of Rolaids. My wife is OK with us moving but it will take us a while to get there.”

  “If we’re going to do this, I want you here this afternoon. My AI says you can catch a commercial flight out of Sky Harbor at… 10:37 and be here by late afternoon.”

  “But… but, I have… have to give notice at my job. Help my wife get started on packing our house and selling it, and, and…”

  “Those are problems money can solve and D5R is willing to spend it. We’ll double any penalty clauses in your contract for leaving without notice and reimburse your company three months of your salary. We’ll pay for high end movers to do everything related to moving you. Your wife will only have to say ‘pack that, move this.’ We’ll pay all real estate fees and cover any reasonable losses you think you have incurred from selling your home in a hurry. We’ll cover your wife’s salary from her last day there for six months or until she finds a job here whichever is first.”

  “But, but…”

  “Wilson! Do you think human civilization is at risk or not?”

  “Uh, I, I, I do, but…”

  “Then, pack a bag and get out here. The rest of this stuff is trivial, isn’t it?”

  Daster audibly swallowed, then practically gasped, “Uh, yes.” With more resolve he said, “I’ll be on that plane and see you at your facility ASAP this afternoon.”

  “All right! My AI has made you a reservation for the plane and for a car rental when you get here, charged directly to D5R.”