“Hi, I’m Justin Phillips from Providence, Rhode Island, and I’m seventeen. How do you find Mars? I mean, it’s a long way away and moving. How do you know which way to go?”
“Ah,” said Jeff, “okay, good question. You’re not far from our home, Justin. We live in Newport. Okay, another question for our navigator. Gabe?”
“Hello Justin. Actually, it’s not that hard. Using Johannes Kepler’s laws of planetary motion and Newton’s laws of motion and universal gravitation – the foundations of orbital mechanics – one can predict where in our solar system a planet will be at any given moment. Then it’s simply a matter of calculating what’s called a Hohmann transfer orbit that will intercept Mars’ orbit and put us there when Mars is there. And to get back, we simply do the reverse. So, once we were in orbit around Earth we executed a TMI burn – Trans-Mars Injection – of our Earth Departure Stage, or EDS, at the proper time to get us on our way at a velocity sufficient to escape Earth’s gravitational pull and on the right trajectory. Then we navigate along the way by the stars – celestial navigation – the same way sailors on Earth have been navigating for thousands of years. Occasionally we will have to make a minor course correction burn with our Service Propulsion System engine, or SPS, but our initial trajectory will take us pretty close to Mars. It’s all just a matter of mathematics. Fortunately, the planets and stars are very cooperative, and generally go where they’re supposed to.”
Jeff shook his head. “Don’t believe a word she says, Justin, it’s not that easy. Gabe happens to have a doctoral degree from Caltech in aeronautics and applied physics. For her, it is easy. For the rest of us, um, not so much.” He chuckled. “But that’s why we brought her along.”
Jeff could hear giggling in the background, “Hi, I’m Elaine Lucatero and I’m eighteen and live in San Antonio, Texas. And my question is…” more giggling, “… since there’s no gravity in space, do you have to wear a bra?”
Jeff buried his face in his hands, “Oh god, help.”
Abby laughed, shaking her head, “Um, Elaine, that sounds like a physics question.” She glanced at Gabe, “Uh, why don’t you take this one.”
Gabe cringed. “Oh my gosh. Um, wow. I anticipated a lot of different questions, but this wasn’t one of them. Well, actually Elaine, it’s not an entirely bad question, and Abby’s right, it is a matter of physics. Um, certainly gravity, over time, is not a girl’s best friend. And, yes, right now we’re living in a zero gravity environment. Though that’s not entirely true. We actually do have what’s called microgravity; it’s measurable, but not perceptible. So yes, for all practical purposes – including this one – we are weightless. So to answer your question, no, from that perspective we don’t need to wear a bra. However…” and she found herself struggling with laughter again, “… however… sorry, never thought I’d be applying momentum to this subject. The, uh, 17th century English mathematician, John Wallis, demonstrated that an object in motion tends to remain in motion.” Abby was absolutely howling and drifting out of her seat. Gabe looked at her, “Shut up. If you drift off somewhere, I’m not gonna go get you. Sorry Elaine, where was I? Oh yeah, momentum. Um, our problem here isn’t gravity, it’s momentum. And like Wallis postulated, things – um, all things – in motion tend to remain in motion. So in fact, yes, we do wear bras, generally comfortable sports bras, as the issue is restraint rather than support. Please, next question!”
“Hello, this is really great. Boy, I sure hope I can be an astronaut someday. I’m John Rhyne from Sioux City, Iowa, and I’m fifteen. What’s your day like? What do you do?”
Jeff finally got his laughter under control, “Hello John. Well, I hope you get your wish. Inspiring young people is, in part, one of the reasons we’re doing this. I’m gonna let Susan answer your question, since she basically runs our schedule.”
“Hi John,” Susan waved at the camera, “great question, and a real important one. Since the beginning of manned space flight we’ve learned that there are a wide range of potentially serious problems for people in space, particularly long periods in space, and we will be in space for seven months. That’s a long time. We’ve learned an enormous amount from Skylab, the Russian Mir space station, and the ISS, and one of the things we’ve discovered is that one way to avoid a lot of the potentially serious physical and mental problems is to have a well-regulated and defined schedule. There’s no day or night, per se, in space. So if you’re not careful, you lose all perspective of routine and your body never adjusts. So what we’re doing is, we have a clock, a 24-hour clock that we set to our time, Eastern Daylight Time, before we left Earth, and that clock determines our day. We get up around 6:30 a.m., have breakfast and start our day’s work. We break for lunch around noon, and then work in the afternoon until around 5:00. Then there’s dinner and an evening of relaxing and around 10:00 p.m., lights out and bedtime. For many people, sleeping in space can be very difficult. It’s not like being in bed at home. You’re weightless and there’s always some anxiety. It’s hard, and very difficult to adjust to. But sticking to a tight schedule makes that a little easier. So far as what we do during the day is concerned? A lot of things. There’s navigation to check on, and maintenance checks on the ship, and the status of our other ships and modules… that kind of thing. We also do a lot of exercise – a couple hours a day, each – on a treadmill or bicycle, to keep our bodies in shape. We also have a Bowflex to keep our muscles toned. We also study a great deal. Our preparation time for this mission was comparatively short, about four years, and one thing that we didn’t have a lot of time for was learning about Mars itself: the planet’s geology, weather patterns, atmospheric conditions, and the like. So, we’re catching up on a lot of that now. But in the evening, we relax, talk about what we’ve done during the day or plan to do tomorrow. We have a very large library of books, music, and videos on the computer, so we may take a look at something there. We’re getting pretty good at a variety of card games like bridge, canasta and hearts. Chess is also popular. We try to avoid poker because Abby just takes all our money. So our days are pretty regimented. But that’s necessary to help us maintain both our physical and mental health.”
“Hi, I’m Mary Holman from Fort Wayne, Indiana and I’m fifteen. What do you eat? Do you have regular food or is everything like liquid in plastic bags?”
“Oh man, if it had been that bad, I wouldn’t have come.” Jeff laughed and motioned to Susan, “Yours again.”
“Hi Mary, no we eat pretty normal food. It’s a mix of freeze-dried and solid foods, generally low in bulk to reduce waste but all in all, not much different than a normal Earth diet. We have scrambled eggs and sausage and sometimes pancakes for breakfast, sandwiches or chili or something like that for lunch and steak, potatoes, fish, chicken, vegetables… the usual, for dinner. We also take regular vitamin and mineral supplements to properly maintain our body chemistry. But our diet and exercise routine is geared toward maintaining a pretty constant body weight and general good health. And good physical health contributes to good mental health. So, we actually eat pretty well. One other thing I might note, Mary, owing to the migration of bodily fluids from the lower to upper body in microgravity, one’s taste buds don’t seem to work quite as well. So, we’re all developing a taste for spicy foods. And, in anticipation of such, we brought plenty of spices.”
“Hello Ares, my name is Dennis Peterson and I live in Springfield, Missouri, and I’m thirteen, and my question is: How fast are you going?”
Jeff glanced at Gabe. “All yours. Keep it simple.”
“I’ll try. Hello Dennis, good question, but not as easy to answer as you may think. Velocity is relative. How fast are we going? Well, relative to what? I’ll give you a couple examples.” She glanced at the trajectory display. “Right now, relative to Earth – where you are – we’re traveling at a velocity of approximately 4,056 meters per second. In a term more useful to you, that would be about 9,073 miles per hour – a bit faster than your family car can go. That
is our Earth departure velocity. Now, relative to Mars, we’re going a bit faster.” She again glanced at the display. “That would be 19.07 kilometers per second, or about 42,660 miles per hour. And the reason for that difference is because of where Mars is at present in its orbit around the sun and our actual solar velocity. We’re closing on Mars very quickly right now, but that will slow down considerably as we get closer to it. Now, relative to the sun which, for all practical purposes, is the actual velocity at which we are traveling through space – that is, if we had mile markers out here – we’re going 31.47 kilometers per second, or about 70,400 miles per hour. And the reason for that is that, relative to the sun, we have to add our velocity relative to Earth to Earth’s rotational velocity around the sun, which is about 66,619 miles per hour. Putting our solar velocity into some perspective, if you had a car that could travel at 70,400 miles per hour, you could drive all the way around the world, at the equator, in just over 21 minutes. Of course, you couldn’t actually do that because at that velocity you’d launch right off the planet and into space. So, that’s probably a more complicated answer than you were hoping for but, as I said, it’s not as simple a question as it sounds.” She grinned at the camera. “Welcome to the world of orbital mechanics.”
“Hello. Oh gosh, I can’t believe I got picked. Hi, I’m Priscilla Burris from Orlando, Florida, and I’m sixteen, and I watched your launch from the Visitor’s Center. Wow! It sure was loud. That must have been quite a ride. Um, what’s it like being weightless?”
“Hi Priscilla. Hey, that’s great. Glad you got to see the launch. I think you’re the first person we’ve spoken with since liftoff that was actually there. Yes, it is loud. We watched the Juliett launch the day before from the Apollo/Saturn V Center and, trust me, it’s a lot louder there than it is over at the Visitor’s Center. In fact, it’s so loud you can see the pressure wave from the four SSME engines on the J241 coming across the lagoon, three and a half miles away. Anyway, living in weightlessness is, um, different. There’s so much that we Earthlings take for granted in the presence of gravity. We expect to stay put in our bed at night. For that matter, we expect our bed to stay put. We expect food to stay on our plate, milk in our glass, water in the bathtub, our feet on the floor, and we expect hot air to rise and cold air to sink.” Jeff shook his head. “None of that happens up here, because there is no up or down.” He reached into his pocket, pulled out a pencil and held it in front him. “On Earth, when you drop something, you expect it to fall.” He let go of the pencil and it just floated there. “Nope, not here. Now, parking your pencil in midair may at times be convenient. However, trying that with a bowl of soup presents a whole bunch of problems, cause the soup doesn’t know that it’s supposed stay in the bowl. I think the most challenging adjustment for us was getting used to sleeping in space. As Sue said earlier, it does take some getting used to. On the other hand, you can sleep anywhere. Perhaps I can demonstrate.” He glanced at Abby. “Would you mind?”
“No.”
Jeff retrieved the pencil, grabbed Abby, held her out in front of him, and let go. She stayed put. “Go to sleep.”
Abby closed her eyes.
“There, nothing to it. And, if she’s in the way, you just move her.” Jeff grabbed her waist, turned her upside down, and moved her aside. “Isn’t that convenient? And if you’re in the mood for some entertainment…” He pulled Abby back over and started her spinning. “Hours of fun for the whole family. Now, if I get Abby spinning fast enough, she’ll perceive it, owing to the Coriolis effect on her inner ear. But with her eyes closed she’ll have no idea how she is oriented; right-side up, upside down, no clue, as she has no gravitational point of reference.” He grabbed Abby, stopped her spinning and pulled her back to her chair. “Thank you.”
“You’re welcome.”
“Now, Priscilla, you see us sitting here in chairs. We aren’t actually ‘sitting’ in them, we’re just kind of floating somewhere near them. We have furniture in the habitat and, for the most part, it’s all oriented in the same direction, giving us sort of a virtual up and down. It doesn’t really exist, but it’s a kind of a psychological crutch. It gives us a visual plane of reference, the illusion of up and down, which makes it a little easier to adapt to what would otherwise be a very strange environment. Okay, um, I think we can answer a lot of your questions by just taking you on a tour of the ship. So, I’m going to put on a little headset camera and give you a guided tour.” Jeff donned a Bluetooth video headset. “Gabe? We have video?”
“Hang on.” She drifted over to the communications console and punched a couple buttons. “Uh… yeah, you’re on.”
“Okay, well we’re in what we call the commons. It’s sort of our combination family room, dining room, kitchen, communications room, etc. We spend a lot of time in here. I’ll try not to move my head around too fast and get everyone dizzy.” He slowly panned around the room. “This is the largest room in the habitat, comprising about 25% of the Sundancer’s total volume. The Sundancer was built for us by Bigelow Aerospace and is an inflatable habitat. It’s cylindrically shaped with rounded ends, and is 28.5 feet long, 20.7 feet in diameter, and weighs about 19,000 pounds, not including all the interior fixtures, furniture, and equipment. The metal framework you see along the centerline here is called the truss, and it runs the length of the Sundancer, and is about three feet square. When the Sundancer launched, the outer skin – which is about a foot thick and is constructed of around two dozen layers of various materials such as Kevlar, Vectran, and Nomex – was collapsed around the truss, and the module was not inflated until it was in orbit. So everything you see – walls, furniture, equipment – was in fact stored within the truss or wrapped around it, and we’ve spent most of the past week assembling it all.
“Over here is our kitchen, which includes most of the appliances and laborsaving devices you have at home. Ours are just a bit smaller and a lot more energy efficient, as we operate entirely on solar power. Now, you can see that our sink is enclosed in a clear Plexiglas box, which has two holes in the front with gloves attached inside. It works kind of like a fume hood in a chemistry lab. There’s a fan at the top that blows air in and another fan in the drain plumbing that draws air and water out. And the whole thing is sealed. This prevents water and other materials from wandering off. Everything that we do food preparation-wise is done within sealed containers or inside the sink’s hood. The only things that get opened are our trays of solid food when it’s ready to eat. We also have a dishwasher that works more or less like the one you have at home, except that it also has fans in it – top and bottom – to evacuate the water.
“Now here’s something you may find interesting.” Jeff pulled the tablecloth off their dining table. “Our dining table, as you can see, is perforated. And in the pedestal beneath it is a fan that draws air through the perforations, creating something of a vacuum. Any food particles that start to drift off get sucked back onto the tablecloth. That way we don’t have food drifting all over the ship, clogging up our ventilation system filters, and making a lot of extra work for us; a blueberry pancake that wanders off is not hard to retrieve, breadcrumbs are another matter. It also has the added advantage of keeping things that are set on the table, on the table. Further, over the table you see this hood. When we dine, we switch the commons ventilation exhaust to this hood, and anything that does escape from the table – crumbs, droplets of liquid, an errant lima bean, whatever – gets sucked up into this washable filter.
“Over here is our information suite. It provides us with communications, navigation, and life support systems status. Most of these comm units are just remote heads as the actual communications equipment is in the command module that is docked on the aft end of the Sundancer. We do have a couple transceivers here in the Sundancer, but they’re primarily backups. We have antennas on the command module, the EDS, and the Sundancer. Abby and I went outside – performed an EVA – a couple days ago to set up the Sundancer’s hi-gain antenna, whic
h is our biggest, and the one we’re using right now. We also set up our telescope, which we use for sightseeing and navigation, it being far easier and more powerful than the telescope in the command module’s guidance and navigation suite. We can also access the CM’s sextant and navigation computer from here so we don’t have to climb into the CM to do our navigation. On this display, for example, you can see our transfer orbits, both from the perspective of Earth to Mars, and within the solar system, along with a whole bunch of orbital parameters, distances, times, and the like,” he chuckled, “all of which only Gabe understands. Also, as you can see, we have a widescreen TV, along with literally thousands of films and videos to watch. We also have an online library, which is quite substantial.
“Over here is one of the Sundancer’s three windows. Shall we take a peek outside?” Jeff pulled over to the window and looked out. “Alright, there you are, space is about a foot away. Except for stars there’s not much to see. If you’re familiar with your constellations you’ll notice Hercules down there on the lower right, Draco above and to the left, and above and left of it, Ursa Minor. And at the end of the Little Bear’s tail is Polaris, the North Star.
“Alright. On the other side of this central wall are the four bedrooms, two above the truss and two below. I’ll take you into my room. There are no doors in the walls, everything is accessed through the truss.” Jeff pulled through an opening into the truss, and glanced in both directions. “Okay, now we’re inside the truss and, as you can see, it’s basically just a narrow tunnel with ventilation ducts and water and drain pipes and electrical conduit, and a little room to move around, but not much.”
He pulled on into his bedroom. “Okay, here’s my little room. There are doors inside each to close off the room, and we usually close them whenever we’re going to be in here for a lengthy period, particularly when we sleep, to create a good ventilation pattern in the room. As you can see, the room’s not very big. They’re shaped like a quarter slice of cake: two 90-degree walls, joined by a quarter-circle wall, with flat walls on either side. The volume of each bedroom is just about 400 cubic feet. In a typical house with eight-foot ceilings, that would encompass a floor area of about 50 square feet. Say, about seven by seven feet. Back home, my closet is bigger than that, a lot bigger. Accommodations are pretty sparse: desk, chair, bed, computer, a couple lights, some fans, clothes cabinet, and… well that’s about it. You’ll notice that all our chairs have seatbelts. It’s not because we need them as you would in a car, they just help to keep us put. The force generated by something as simple as writing or typing is sufficient to push us away from the desk, and that’s a little annoying. So, the seatbelts simply keep you in the chair.”
Margaritifer Basin (Margaritifer Trilogy Book 1) Page 65
