CHAPTER 15
Paul Gesling was spending every spare moment in front of the 3D holographic projector studying the schematic drawings and performance specifications for all of the systems that comprised the spaceship that would carry them to Sutter’s Mill. The newly named Tamaroa would be their home for the next several months and he was determined to know as much about her as he could before they left Earth.
Named after the U.S. Coast Guard cutter made famous in the book The Perfect Storm, their Tamaroa would also be a rescue ship. Instead of rescuing the crew of sinking sailboat and then a swamped National Guard helicopter, they would hopefully be saving an entire city…or more.
At least the original Tamaroa looked like a ship, Gesling thought to himself.
The nuclear-powered rocketship didn’t look much like a traditional spaceship to Gesling. To him it appeared ungainly and fragile. Designed and originally built to carry a four- to eight-person crew to and from Mars over a two- to four-year period, the Tamaroa was essentially two spacecraft connected by a long truss. Gesling walked the length of the scale-model projection of the Tamaroa, stopping occasionally to change his viewing angle and memorize one surface feature or another of the craft that would have taken the first humans to Mars had it not been commandeered by Gesling and his crew to save the Earth.
“Amazing, isn’t she?” Paula Downey’s voice startled Gesling, who hadn’t noticed her walk into the room from the door to his right. She walked crisply toward Gesling, her head held high and facial expression showing all the pride a parent would wear had their offspring just been accepted at Harvard. Only the Tamaroa was her child—and it was going into deep space, not Harvard.
“Amazing isn’t the word I would have used, but it’ll do,” replied Gesling.
“You’ll think she’s amazing when you ride her and feel her thrusting…. I mean, when you’re inside her and…and, well, that didn’t exactly come out like it should have.” Downey turned red.
“That’s okay. I know what you mean. I’ve been to the Moon, remember? There’s nothing like the thrill of feeling the engines ignite and leaving Earth orbit.” Paul laughed.
“I’ve been told its better than sex.” Paula blushed a bit more.
“I wouldn’t go that far but that’s a discussion best left to another time—and with someone else.” Paul didn’t want to come off as a prude but at the same time he was a married man and didn’t want to get into an uncomfortable situation with the engineer.
“Right. I’m sorry. I wasn’t thinking. What do you know about the truss?”
“Not much. Tell me.” Paul was glad she was changing the subject.
“Well, at one end of the truss are the nuclear rocket engines and the propellant tanks. Toward the middle are the radiators. At the opposite end is the crew module. Most importantly, the truss keeps the crew safely a tenth of a mile away from the fission reactor which powers and propels the ship. Without the truss providing all that separation, she’d have to carry a lot more shielding mass to protect you from the reactor’s stray neutrons. It’s made of composite materials and is stronger than steel.”
“I understand why it’s built the way it is, but that doesn’t keep me from thinking that it doesn’t look like a nuclear rocket ship should look.” Paul shrugged his shoulders and gestured with his hands realizing he was sounding a bit like Captain Kirk the way he was speaking. He paused and took a breath then changed his mannerisms a bit. “I mean, a nuclear ship should be big, yes, but not spindly. It looks too fragile. It should have the physical dimensions of an ocean liner with a proper—big, strong, looking and capable. This looks like, well, like a ship designed by committee.”
“Well, parts of it were designed by committee.” Paula almost sounded annoyed but he wasn’t sure. “You know that. Everything we’ve sent into space has been designed by committee—a committee composed of engineers, scientists, technicians, welders, electricians…”
“Okay, I’ll drop it. But please build the next one to look more like a rocket and less like the ladder of a fire truck.” Paul surrendered the argument.
“Deal. Now what questions can I help answer? Is there anything you don’t understand about her?”
“The radiators. They’re huge. Why are they so big?” Paul was used to rockets, chemical ones, with regenerative cooling and such.
“Ha ha, that gets a lot of smart people,” Paula teased him. “A nuclear reactor puts out a lot of heat. A lot of that heat is transferred to the propellant, that’s how the engine works. But there is a lot of heat that doesn’t get carried away by the rocket exhaust and some of it is used to generate electrical power for the ship. It’s called a bimodal nuclear reactor—it is operated in two modes. One mode produces rocket thrust, the other produces power. But even that doesn’t use up all of the heat generated when the uranium atoms split in the reactor. It’s that waste heat that the radiators have to dump into space.”
“Can’t we use it for something else?” Paul asked.
“Not easily. And unfortunately, unlike here on Earth where we have water to carry away most of the waste heat from a nuclear power reactor, in space we can only radiate. And radiating heat takes a lot of surface area; hence the large radiators.”
“What happens if there’s an accident? Like Fukushima or Chernobyl?” Paul was suddenly thinking of disaster in space and any number of scenarios he’d seen in science fiction movies.
“First of all, that won’t happen. This reactor is designed to fail ‘safe’ and shut down if something goes wrong,” Paula reassured him. “It’s triple redundant. No, if the reactor shuts down, you will have plenty of other things to worry about instead of radiation from the reactor.”
“Explain.” Paul wished he could just fly a rocket he understood, like the Dreamscape, but he knew better.
“Without the reactor, you can’t fire your engines to go anywhere and you won’t have power to keep you warm and the air circulating. If the reactor fails, you’re dead.”
“Oh. Okay then, let’s just make sure that doesn’t happen.” Paul noted the important safety tip.
“We did our best.” Paula raised an eyebrow in a very cocksure way.
“What about solar storms? The Dreamscape has portable shields made of hydrogen-rich plastic that we set up around us if the Sun decides to send a burst of radiation our way. It’s my understanding that you use a water wall around the crew quarters to absorb the radiation and keep exposure low during sleep. But I don’t see that the skin in this model is any thicker around the core module than anywhere else. What gives?”
Paula smiled and motioned toward the core module.
“Hal, show us the magnetic shielding please,” Paula said, enunciating more clearly and certainly speaking louder than previously.
“Deploying now,” came a calm, male and oddly familiar voice from speakers hidden somewhere in the room. Downey was apparently talking to the display computer.
Within the holographic projection, around the core cylinder and the habitat and deploying from the truss were six booms, each with a large black box attached; three on each side of core module and habitat section.
“Did you just call the computer Hal?”
“Yes, I did. I’m a big fan of old science fiction movies. We thought it would be fun.”
“And the voice, you even used the same voice?” Paul got the humor. He liked it, actually.
“That took some doing, but yes. Why not?” Paula asked him.
“Well, for starters, you know that bad things came of that computer. You didn’t program the one on the ship that way did you?” He wasn’t seriously concerned but the lighthearted tone relaxed the two of them a bit. It was something for pilot and engineer to lightly bond over.
“Of course not. The psychs would never have allowed it. Though we were tempted…” Downey said with her disarming smile in full bloom.
“So, tell me more about these magnetic shields. I’ve been reading about the concept for years but I didn’t know it was mature enough to use yet.”
“They wouldn’t be, if you were on a solar-powered spacecraft. But with the nuclear reactor, you’ve got plenty of power available, so why not?” Downey then walked up to the 3D image of one of the deployed booms.
“In this box is a superconducting magnet. It’s made from a new class of high temperature superconductors that don’t have to be kept at liquid nitrogen temperatures of minus 452 degrees. Keeping something near absolute zero is pretty tough. These can operate at temperatures of up to 150 degrees without degrading. And, unlike most other superconductors, they don’t lose their ability to conduct current if the ambient magnetic field is too strong. That makes them perfect for making magnets.”
“Together, when current is flowing, these magnets can shield against all but the most energetic of the galactic cosmic rays and completely shield the crew against radiation in the solar wind and from solar storms. It’s our version of a deflector screen.” She pointed first at the box in front of them and then waived her arms to include all six boom and magnet sets. “The magnets each are capable of producing a three-tesla field. The total combined is a whopping eighteen teslas. That is, like, particle accelerator strong.”
“So the solar radiation gets bent around the ship and doesn’t pass through to the crew?” Paul asked.
“That’s right.” Downy seemed happy that he was following her so easily. “Most of it is deflected back into empty space. The only things we can’t stop completely are the galactic cosmic rays. They are so massive, mostly carbon and iron, and moving so fast that we just can’t build a magnetic field strong enough to stop all of them. Maybe the third or fourth generation system will be able to, but not this one.”
“I bet that saved a lot of weight on the ship,” Paul said.
“Tons. Mostly water. If we had gone with the more traditional approach, we would have needed to put up to three meters of water around the habitat to act as shielding, making it pretty darn heavy to launch or move around.”
“What about the artificial gravity? The ship is designed to slowly spin along the truss axis to simulate the gravity on Mars and there hasn’t been any mention of me training to perform the spin-up and spin-down maneuvers.”
“You won’t be using it much. We designed the ship to include the capability to simulate Martian gravity for the duration of the trip by spinning, but you’re not going to Mars and you won’t be in space long enough to suffer the worst of the biological effects resulting from being in a close to zero gravity environment. So, you will only need to spin up a few hours a week to help prevent any medical issues. This trip will be a short hop for the Tamaroa and the engineers just don’t believe it is worth the risk. We may let you test it on the way home to make sure it works and reduce the risk for the first Mars mission.”
“Having a little gravity would be nice,” Paul argued.
“I wish I could say I understand. I would love to go where you’re going but I wasn’t selected for the astronaut program. Funny, they never really said why.”
“What else have you got to show me?” asked Gesling.
“Lots. Let’s start with the new oxygen regeneration system. It can…”
Paul and Paula spent the next two hours reviewing all the major subsystems in the Tamaroa. At the end, Paul didn’t feel as overwhelmed as he had before. Having the ship’s chief engineer provide personal, though virtual, tour went a long way to alleviate his concerns.
Now all he and his crew had to do was get from the surface of the Earth and into space so they could board the Tamaroa and start the mission.