3D Printing †Applications for Space Exploration

3D Printing – Applications for Space Exploration Puneet Bhalla 3D Printing or Additive Manufacturing (AM) was first tested in 1983 by inventor Chuck Hull. Conventional subtractive manufacturing involves carving out items from a single block of material, whereas AM involves adding plastic or metal layer by layer according to a computer generated design to manufacture a product. Over the years a number of processes that differ in the method of depositing of layers and their binding have been developed. The technology in the earlier years did not evolve enough for it to find mainstream support and its use was restricted to production of computer generated models and prototype research. Advances in metallurgy, miniaturisation and processing have now made it a more viable competitor to conventional manufacturing. It is even being called the third industrial revolution. Commercial enterprises having recognised the transformative potential of 3D printing, both in designing and manufacturing, are increasingly investing in it. It allows faster design iterations, providing flexibility for refinements and variations and produces more accurate 3D scaled models for testing. This helps in accelerating product development and manufacturing with corresponding cost benefits. It helps overcome constraints of conventional manufacturing and allows for more precision in manufacturing to produce more complex parts. The process allows for more cohesive structures and components can be constructed using much fewer parts, making them lighter, sturdier and more efficient. Large factories with their assembly lines can also be done away with. Existing parts can now be redesigned and designers can be more audacious in their pursuits, stepping beyond the constraints of conventional design and manufacturing, while seeking innovative solutions or entirely new capabilities. T he manufacturing process requires less material, reduces wastage during production and is more energy efficient, making it potentially more environment friendly. Objects can be created on demand, thereby eliminating costs, logistical complexities and wastages related to surplus inventories. Initial printers were capable of handling single materials only but the multi-jet technology is allowing combining of materials to produce varied material properties – mechanical, thermal and chemical. Nanotechnology coupled with 3D printing promises exciting opportunities in the future. Already, availability of cheaper printers has made the power of designing and producing publicly available. This democratising of manufacturing has the potential to revolutionise innovation. Market researcher Gartner forecasts that worldwide spending on 3D printing will rise from $1.6 billion in 2015 to around $13.4 billion in 2018.[1] Despite the excitement, there are experts who say that the technology m ight only evolve to supplement the conventional mass manufacturing methods that will continue to be faster and cheaper. They instead favour its suitability for niche and customised production. Space exploration has always been costly due to its requirement of low volume, customised and at times unique components. 3D printing is being seen by the space industry as enabling to the development of future space infrastructure. Various RD efforts both for ground based as also in orbit manufacturing are being supported with an aim to develop parts that could meet the stringent high performance and high reliability criteria required for space operations. NASA along with US rocket engine maker Aerojet Rocketdyne has successfully tested a rocket engine injector and an advanced rocket engine thrust chamber assembly using copper alloy materials, in different configurations.[2] The components proved themselves in tests where they were subjected to pressures of up to 1,400 pounds per square inch and temperatures up to 6,000 degrees Fahrenheit to produce 20,000 pounds of thrust.[3] NASA has claimed that 3D technology enabled designers to create more complex injectors while at the same ti me reducing the number of parts from 115 to just two.[4] This resulted in more efficient processes and also provided better thermal resilience. While the traditionally constructed injectors cost about $10,000 each and took six months to build, the 3D printed versions cost less than $5,000 and reached the test stand in a matter of weeks.[5] These tests have provided confidence in the technology and paved the way for its use in replacing other complex engine components. Already, many small 3D produced parts are flying in space onboard US and European satellites and more are being developed. ESA and European Commission’s Additive Manufacturing Aiming Towards Zero Waste Efficient Production of High-Tech Metal Products (AMAZE) project, has 28 European companies as partners that are looking at perfecting 3D printing of high quality metal components for aerospace applications. NASA is also evaluating using the technology for manufacturing composite CubeSats. China has also started investing in this technology and on its last manned space mission in 2013, their taikonauts occupied customised 3D printed seats. In December 2014, Chinese scientists have claimed to have produced a 3D printing machine, which could be used during space missions. Private companies the world over are investing heavily in the technology for aerospace applications.Japanese Space Agency JAXA along with Mitsubishi is working at producing 3D components for a new large-scale ro cket that the two are expected to develop by 2020. Swiss company RUAG Space has built an antenna support for an Earth observation (EO) satellite that will replace a conventionally manufactured one after tests. The engine chamber of SuperDraco thruster to be used on the crew version of SpaceX’s Dragon spacecraft, capable of producing 16,000 pounds of thrust, is manufactured using 3D printing. A team of engineering students from the University of Arizona, with help from 3D printing company Solid Concepts, recently assembled a 3D printed rocket within a day and successfully tested it. Planetary Resources, a private company seeking space exploration and asteroid mining has collaborated with a company, 3D Systems for developing and manufacturing components for its ARKYD Series of spacecraft using its advanced 3D printing and digital manufacturing solutions.All these efforts are providing solutions that are cheaper, have lesser parts and have comparatively shorter developmental tim elines. In the future, the technology could be used for entire structure fabrication that would involve integrating many of the system’s geometries into structural elements during production. This would reduce the number of parts, eliminate most joints or welds, simplify the design and production, reduce the number of interfaces and make the system more efficient and safer. Such vehicles would better sustain the rigours of launch and space exploration. Integrated structures would even enable reconceptualising space architectures, impacting on their design, sizes and functionality. The most exciting opportunity is 3D printing of objects in space – an idea that has the potential to cause a paradigm change in the way we look at space exploration. The concept has been debated for decades and NASA has also conducted some experiments since theSkylab space stationof the 1970s. In 2010, it collaborated with a US company Made in Space to develop and test a 3D printer that could operate in microgravity aboard the International Space Station. The microwave oven sized printer, previously tested on suborbital flights, was installed on board the station on 17 November. After two calibration tests, on 24 November 2014, on command from the ground controllers, the printer produced the first 3D object in microgravity. The object was a faceplate of the printer itself, demonstrating that the printer could make replacement parts for itself. Initial results have shown that layer bonding might be different in microgravity, but this would have to be substantiated by further te sting on more such produced parts in the future. These parts will subsequently be returned to Earth where they will be compared with similar samples made by the same printer before launch and also analysed for effects of microgravity on them. This would help in evaluating the variance and possible advantages of additive manufacturing in space and in defining the roadmap for future developments. Meanwhile, Europes POP3D Portable On-Board Printer designed and built in Italy is also scheduled for installation aboard the ISS next year. Producing parts and structures in space potentially provides a host of benefits. Structures being constructed on Earth have to be built in an environment that is different from where they would operate. These parts also have to survive the vibrations and high ‘g’ stresses of launch. Freed from these constraints, novel space architectures, more optimised to the microgravity environment, can be imagined and developed. 3D printers in space would enable astronauts manufacture their own components and tools, undertake repairs, replace broken items and respond to evolving requirements without being dependent on support from Earth. This would bring down logistical requirements related to deployment of structures in space, while improving mission efficiency and reliability. NASA is even funding research into the possibility of making food in space using a 3D printer. This would overcome the current issues related to food shelf life, variety and nutritional requirements. It would be possible to have human missions of longer duration and venturing much further into space. Made In Space has an ongoing project R3DO that seeks to recycle 3D produced broken or redundant parts to create new ones, thereby helping reduce space waste. The technology in the future could be used for space based construction of large structures – even entire spacecraft in space. Another concept being envisaged is the use of 3D printing for construction of large housing structures, roads and launch pads using the resources available in-situ on celestial bodies. Concrete houses being produced through 3D printing have already been demonstrated. Both NASA and ESA are exploring printing of objects using Regolith, the powdery substance that covers much of the surface of the moon. Besides the huge savings in cost and time, such habitats would be more suited to the local hazardous environment. The printers could either be controlled from Earth or make use of automation technology on robots or artificial intelligence. These capabilities would be a great step forward for human interplanetary exploration. 3D printing is making rapid strides and its applications are being recognised by industry. Scientists are working to smoothen out the inefficiencies and shortcomings of the processes as also evaluating potential opportunities. Developments in the space domain are promising but these would have to be put through rigorous testing before being cleared for regular use. Qualification and verification standards that would eventually be defined for this new industry would have to be more stringent for use in space. More complex printers will have to be devised for construction of larger parts. Currently, most construction is focussed on building frames and structures but in the future would also require manufacturing techniques to producing working electronic components.[6] For production in space, bigger printers would bring forth issues of mass, volume and power requirements, each one of which is critical for space launch and operations. Some methods would also have to be devised to bring together the parts so produced. The new technology provides an avenue for space industries the world over to graduate to common standards of software as well as hardware. This would allow a larger pool of scientists and engineers coming together learning and benefiting from each other. At the same time, and the policy makers would also have to come up with requisite regulatory framework. In India, 3D printing technology is still in its infancy and its penetration is low among industry is low. Most institutions continue to use it for producing 3D Computer Assisted Design (CAD) models and for prototype testing. Some global additive manufacturing companies have gained foothold in India through collaborations and there are some indigenous initiatives too. Isolated research is being undertaken by some private and public sector entities including the DRDO. Private companies are collaborating with some engineering institutions like IITs to promote research. There is also the Additive Manufacturing Society of India (AMSI) that seeks to promote 3D printing Additive Manufacturing technologies. Applications for Defence and Aerospace are two important sectors that most companies are focussing on. ISRO chairman, after the successful Mars Orbiter Mission, mentioned 3D Printing as one of the technologies that he wishes to see Indian engineers build upon in the future. India has la gged behind in conventional manufacturing and metallurgy. It could leverage its advances in software technology and collaborate with international experts to initiate activities in this sunshine sector. While increased awareness and commercial benefits will drive industry to invest in the sector, space initiatives would require the government to play the vital supporting role while seeking participation from industry and academia. Investments would be required in planning and executing the supporting infrastructure required to enable fabrication processes, in creating knowledge and capabilities through education and training and for provision of adequate RD facilities. [1] â€Å"From earphones to jet engines, 3D printing takes off†, 09 November, 2014 [2] â€Å"3-D Printed Engine Parts Withstand Hot Fire Tests†, 14 November, 2014 [3] TheAerojet Rocketdyne RS-25engine powered NASA’sSpace Shuttleand will power the upcoming Space Launch System (SLS), a heavy-lift, exploration-class rocket currently under development to take humans beyond Earth orbit and Mars. [4] ww.space.com/22568-3d-printed-rocket-engine-test-video.html [5] http://www.space.com/22119-3d-printed-rocket-part-test.html [6] http://www.space.com/26676-3d-printing-international-space-station.html

Physics Essay -- Steer Wrestling Science Papers

Physics You can find a law of physics in everything that you do. It does not matter if you are doing complex scientific experiments, working as a laborer in a field, or enjoying your favorite pastime, you are involved in putting the laws of physics to work. I will try to demonstrate this as I discuss the laws of physics that are involved in my favorite pastime, which is steer wrestling. The art of steer wrestling is complex and simple all at the same time. To start, let’s define what exactly steer wrestling is. Steer wrestling is a rodeo event that is also known as bull dogging. This is the event where there are two mounted cowboys that run along the side of a steer. When they get close to the steer the cowboy on the left hand side climbs off onto the back of the steer, grabbing the steer by the horns. Keep in mind if you will that both the cowboys on the horses and the steer are running at full speeds while this dismounting is taking place. Once the cowboy has the steer by the horns, the cowboy must change the steer’s direction and wrestle him to the ground. Since this is a rodeo event and a competition, you have to do all of the above as fast as you can. Steer wrestling is a timed event that is started when the steer leaves the chute, and ends when the steer is lying on its side with all four feet facing the same direction. Now that we know what steer wrestling is, let’s tie it in with a couple of things that deal with physics. As I already mentioned above, the first step is crawling off of a horse that is running full speed onto the back of a cow that is traveling at its full speed as well. Any time you have masses traveling at speeds you have momentum. We will first discuss momentum and the changes in momentum th... ...ipetal force, and torque are just a couple of the many aspects of physics involved in this process. I believe that the use and understanding of physics can help in understanding why things work better then others, and how to be a more successful steer wrestler. A specific example is the fact that I now am more aware of where I locate my hands on a steer’s horn, and also I am more conscience is trying to be the center of mass. By being able to do this, I have taken my performance to a higher level and can back good ideas with proof from science. Bibliography 1.Kirkpatrick, Larry D. Wheeler, Gerald F. Physics: A World View. (Fourth Edition). Hartcourt, Inc. 2001. 2.Spence, Mike. â€Å"A Cowboy For All Eras† ProRodeo Sports News. 30 April, 2003. 3.Benton Franklin Fair & Rodeo. Steer Wrestling. 20 August, 2002. http://www.bffairrodeo.com/rodeo/steerwrestling.html

The Message in Spike Lee’s Movie Do the Right Thing Essay -- Movies Fi

The Message in Spike Lee’s Movie Do the Right Thing In an attempt to enlighten audiences with a powerful message about the cancer that hate and violence can bring to a society; writer, director, Spike Lee brings Do the Right Thing to the screen. Fusing a powerful story with creative film making, Lee gives us an insider’s look at life on a blistering summer day in Brooklyn. To create an atmosphere that both looks and almost literally feels like possibly the hottest day of the year, Lee uses orange and yellow filters throughout the film. Objects, as well as people seem to glisten in the light. Even scenes shot indoors have beams of light coming through windows and doors. The use of lighting is only one technique Lee uses to create a realistic feel for this film, which is pertinent w...

Genital Mutilation In Sudan :: essays research papers fc

The lights are dim and the voices quiet. Tension fills the room where Nafisa, a six-year-old Sudanese girl lies on a bed in the corner. Her aunt, 25-year-old Zeinab, watches protectively as her niece undergoes the procedure now known as female genital mutilation (FGM), formerly called female circumcision. In this procedure, performed without anaesthesia, a girl's external sexual organs are partially or totally cut away. Zeinab does not approve. For the past year she has been trying to persuade her mother and sister to spare Nafisa from the procedure. She lost the battle with her family, but she will stay at her niece's side. She watches Nafisa lying quietly, brave and confused, and remembers her own experience. Zeinab underwent the procedure twice. At six years old she had the more moderate form of FGM, called Sunni, in which the covering of the clitoris is removed. When she was 15 the older women of her family insisted she have the Pharaonic form, which involves removal of the entire clitoris and the labia and stitching together of the vulva, leaving just a small hole for elimination of urine and menstrual blood. Zeinab still remembers the pain, the face of the women performing the procedure, the sound of her flesh being cut. She also remembers bleeding and being sick for weeks. This extreme form of FGM has been performed on 82 per cent of Sudanese women, according to a recent survey. Today, 85 to 114 million girls and women in more than 30 countries have been subjected to FGM. Female genital mutilation has long been performed to ensure chaste or monogamous behaviour by suppressing female sexuality. It is commonly -- although erroneously -- attributed to religious edict. In fact, neither Islam nor Christianity officially sanctions it. FGM is dangerous. It is estimated that untrained traditional birth attendants perform two thirds of the procedures. They typically have limited knowledge of health and hygiene and often use inadequately cleaned traditional instruments. Side effects of FGM include trauma, bleeding and haemorrhage; pain, stress and shock; infections (which can be fatal); painful and difficult sexual relations; obstructed labour and difficult childbirth; and psychological trauma. The effects can last a lifetime. The practice was declared illegal in the Sudan in 1941, but that did little to stop it. About 90 per cent of northern Sudanese women have had it done. Why does FGM continue? In surveys, the most common reason

Night World : Soulmate Chapter 11

Hannah stirred. She vaguely felt that something was wrong, something needed doing. Then she remembered. The car! She had to stay awake, had to keep the car on the road. . . Her eyes flew open. She was already off the road. The Ford had gone roving over the open prairie, where there was almost nothing to hit except sagebrush and tumble-weeds. It had ended up with its front bumper against a prickly pear, bending the cactus at an impossible angle. The night was very quiet. She looked around and found that she could see the light of Chess's house, behind her and to the left. The engine was off. Hannah turned the key in the ignition, but only got a grinding sound. Now what? Should I get out and walk? She tried to concentrate on her body, to figure out how she felt. She ought to feel terrible-after all, she'd lost blood and swallowed who knew what kind of poison from Thierry's veins. But instead she only felt strangely dizzy, slightly dreamy. I can walk. I'm fine. Holding on to her length of dowel, she got out of the car and started toward the light. She could hardly feel the rough ground and the bluestem grass under her feet. She had gone about a hundred yards toward the light when she heard a wolf howl. It was such a distinctive sound-and so incongruous. Hannah stopped in her tracks. For a wild moment she wondered if coyotes howled. But that was ridiculous. It was a wolf, just like the wolves that had attacked her at Paul's. And she didn't have anything made of silver. Just keep walking, she thought. She didn't need the cool wind voice to tell her that. Even in her lightheaded state, she was frightened. She'd seen the savagery of teeth and claws close up. And the part of her that was Hana of the Three Rivers had a gut-deep fear of wild animals that the civilized Hannah Snow could never begin to approach. She gripped her stick in a clammy palm and kept walking grimly. The howl sounded again, so close that Hannah jumped inside her skin. Her eyes darted, trying to pick objects out in the darkness. She felt as if she could see better than usual at night-could the vampire blood have done that? But even with her new vision, she couldn't spot anything moving. The world around her was deserted and eerily quiet. And the stars were very far away. They blazed in the sky with a cold blue light as if to show how distant they were from human affairs. I could die here and they'd go right on shining, Hannah thought. She felt very small and very unimportant-and very alone. And then she heard a breath drawn behind her. Funny. The wolf howls had been so loud, and this was so soft†¦ and yet it was much more terrifying. It was close-intimate. A personal sound that told her she definitely wasn't alone. Hannah whirled with her stick held ready. Her skin was crawling and she could feel a wash of acid from her stomach, but she meant to fight for her life. She was at one with the cool wind voice; her heart was dark and cold and steely. A tall figure was standing there. Starlight reflected off pale blond hair. Thierry. Hannah leveled her stick. â€Å"What's the matter? Come back for more?† she said, and she was pleased to find her voice steady. Husky, but steady. She waved her stick at him to show what kind of â€Å"more† she meant. â€Å"Are you all right?† Thierry said. He looked-different from the last time she'd seen him. His expression was different. His dark eyes seemed pensive again, the sort of expression a star might have if it cared about anything that was going on underneath it. Infinitely remote, but infinitely sad, too. â€Å"Why should you care?† A wave of dizziness went through her. She fought it off-and saw that he was stepping toward her, hand reaching out. She whipped the stick up to the exact level of his hand, an inch from his palm. She was impressed with herself for how fast she did it. Her body was moving the way it had with the werewolves, instinctively and smoothly. I suppose I had a life as a warrior, she mused. I think that's where the cool wind voice comes from, just the way the crystal voice comes from Hana of the Three Rivers. â€Å"I do care,† Thierry said. His voice said he didn't expect her to believe it. Hannah laughed. The combination of her dizziness and her body instinct was having an odd effect. She felt brashly, stupidly overconfident. Maybe this is what drunk feels like, she thought, her mind wandering again. â€Å"Hannah-â€Å" Hannah made the stick whistle in the air, stopping him from coming any closer to her. â€Å"Are you crazy?† she said. There were tears in her eyes. â€Å"Do you think that you can just attack me and then come back and say I'm sorry' and it's all going to be okay? Well, it isn't. If there was ever anything between us, it's all over now. There is no second chance.† She could see his face tense. A muscle twitched in ~ his tight jaw. But the strangest thing was that she could have sworn he had tears in his eyes, too. It infuriated her. How dare he pretend to be hurt by her, after what he'd done? â€Å"I hate you.† She spat the words with a force that startled even her. â€Å"I don't need you. I don't want you. And I'm telling you for the third time, keep the hell away from me.† He had opened his mouth as if he were about to say something, but when she got to ‘I don't need, you,' he suddenly shut it. When she finished, he looked away, across the shortgrass prairie. â€Å"And maybe that's best,† he said almost inaudibly. â€Å"For you to keep away?† â€Å"For you to hate me.† He looked at her again. Hannah had never seen eyes like that before. They were impossibly distant and shattered and still†¦ like the peace after a war that killed everyone. â€Å"Hannah, I came to tell you that I am going away,† he went on. His voice was like his eyes, bloodless and quenched. â€Å"I'm going home. I won't bother you again. And you're right; you don't need me. You can live a long and happy life without me.† If he expected her to be impressed, she wasn't. She wouldn't believe words from him anymore. â€Å"There's just one thing.† He hesitated. â€Å"Before I go, would you let me look at you? At your neck. I want to make sure that†-another fleeting hesitation-â€Å"that I didn't hurt you when I attacked you.† Hannah laughed again, a short, sharp bark of a laugh. â€Å"How stupid do you think I am? I mean, really.† She laughed again and heard an edge of hysteria in it. â€Å"If you want to do something for me, you can turn around and go. Go away forever.† â€Å"I will.† There was so much strain on his face. â€Å"I promise. I'm just worried about you getting indoors before you faint.† â€Å"I can take care of myself. I don't need any help from you.† Hannah was feeling dizzier by the minute, but she tried not to let it show. â€Å"If you would just leave, I'll be fine.† In fact, she knew she wasn't going to be fine. The gray spots were swarming in front of her eyes again. She was going to pass out soon. Then I'd better start for Chess's, she thought. It was insanity to turn her back on him, but it was worse insanity to stand here until she collapsed at his feet. â€Å"I'm leaving now,† she said, trying to sound clear and precise and unlike someone who was about to fall over unconscious. â€Å"And I don't want you to follow me.† She turned and started walking. I will not faint, I will not faint, she told herself grimly. She swung her stick and tried to take deep breaths of the cool night air. But tufts of grass seemed to be trying to trip her up with every step and the entire landscape seemed to rock every time she looked up. I †¦ will†¦ not†¦ faint. She knew her life depended on it. The ground seemed rubbery now, as if her feet were sinking into it and then rebounding. And where was the light that marked Chess's house? It had somehow gotten over to the right of her. She corrected her course and stumbled on. I will not faint†¦. And then her legs simply melted. She didn't have legs. The rest of her fell slowly toward the ground. Hannah managed to break her fall with her arms. Then everything was still and dark. She didn't go out completely. She was floating in darkness, feeling woozy even though she was lying down, when she sensed someone beside her. No, she thought. Get the stick. He'll bite you; he'll kill you. But she couldn't move. Her hand wouldn't obey her. She felt a gentle hand brush her hair off her face. No †¦ Then a touch on her neck. But it was only gentle fingers, running lightly over the skin where she'd been bitten tonight. They felt like a doctor's fingers, exploring to diagnose. She heard a sigh that sounded like relief, and then the fingers trailed away. â€Å"You'll be all right.† Thierry's voice came to her softly. She realized he didn't think she could hear him. He thought she was unconscious. â€Å"As long as you stay away from vampires for the next week.† Was that a threat? Hannah didn't understand. She braced herself for the piercing pain of teeth. Then she felt him touch her again, just his fingertips brushing her face. The touch was so immeasurably gentle. So tender. No, Hannah thought. She wanted to move, to kick him away. But she couldn't. And those delicate fingers were moving on, tracing her features one by one. With the lightest of touches that sent helpless chills through her. I hate you, Hannah thought. The touch followed the curve of her eyebrow, trailed down her cheek to her birthmark. Hannah shivered inwardly. It sketched the line of her jaw, then moved to her lips. The skin was so sensitive here. Thierry's fingers traced the outline of her lips, the join between upper and lower. The chills became a fluttering inside Hannah. Her heart swelled with love and longing. I won't feel this way. I hate you. †¦ But a voice was whispering in her mind, a voice she hadn't heard in what seemed like a long time. A crystal voice, soft but ringing. Feel him. Does this feel like that other one? Sense him. Does he smell the same, sound the same†¦ ? Hannah didn't know what to make of the words and didn't want to. She just wanted Thierry to stop. The fingers brushed over her eyelashes, thumb stroking over the fragile skin of her eyelids as if to keep them shut. Then she felt him bend closer. No, no, no†¦. Warm lips touched her forehead. Again, just the barest touch. Then they were gone. â€Å"Goodbye, Hannah,† Thierry whispered. Hannah felt herself lifted. She was being carried in strong gentle arms, moving swiftly and smoothly. It was harder for her to stay conscious than it had been before. She had a strange feeling of tranquillity, of security. But she fought to open her eyes just a crack. She wanted to see his hands. She didn't think there had been enough time for the pencil wound to heal completely. If the pencil wound was there. But her eyes wouldn't open-not until she felt herself being lowered and placed on solid ground. Then she managed to lift heavy eyelids and dart a glance at his hands. There were no marks. The knowledge burned through her-but she didn't have any strength left. She felt her eyes lapsing shut again. Dimly, very far away, she could hear the faint echo of a doorbell. Then a soft voice in her head. You don't have to be afraid anymore. I'm going away-and so is she. Don't go. Wait. I have to talk to you. I have to ask you †¦ But she could feel cold air all around her and she knew he was gone. A moment later she heard the door open, and the sound of Chess's mother gasping. She was on the Clovises' doorstep. People were shaking her, talking to her. Hannah wasn't interested in any of it. She let the darkness take her. It was when she let go completely that she began to dream. She was Hana of the Three Rivers and she was seeing the end of her own life. She saw the bruised and bloody figure of Thierry rising up to kill his torturers. She felt it as her turn came. She looked up and saw his savage face, saw the animal light in his eyes. She felt her life flow away. Then she saw the end of the story. The glimpse of the corridor through time, the recognition of her soulmate. The forgiveness and the promise. And then just shadows. But Hannah slept peacefully in the shadows until morning, unafraid. The first thing Hannah saw when she woke up was a pair of glowing green cat-eyes looking down at her. â€Å"How do you feel?† Chess asked. She was lying in Chess's bed. Sunlight was streaming in the window. â€Å"I †¦ can't tell yet,† Hannah said. Disjointed images were floating in her head, not quite forming a whole picture. â€Å"We found you last night,† Chess said. â€Å"You ran your dad's car off the road, but you managed to make it here before you collapsed.† â€Å"Oh†¦ yeah. I remember.† She did remember; the pieces of the puzzle suddenly clicked together. Maya. Thierry. The attack. The car. Thierry again. And finally her dream. Her own voice saying, â€Å"I forgive you.† And now he was gone. He'd gone home, wherever home was. She had never felt so confused. â€Å"Hannah, what happened? Are you sick? We didn't know whether to take you to a hospital last night or what. But you didn't have a fever and you seemed to be breathing fine-so my mom said you could just sleep a while.† â€Å"I'm not sick.† This was the time to tell Chess everything. After all, that was the reason she'd been running to Chess in the first place last night. But now†¦ now in the bright morning light, she didn't want to tell Chess. It wasn't just that it might put Chess in danger, either from Thierry or the Night World in general. It was that Hannah didn't need to talk about it; she could cope on her own. It wasn't Chess's problem. And I don't even know the truth yet, Hannah thought. But that is going to change. â€Å"Hannah, are you even listening to me?† â€Å"Yeah. I'm sorry. And I'm okay; I felt kind of dizzy last night, but now I'm better. Can I use your phone?† â€Å"Can you what?† â€Å"I have to call Paul-you know, the psychologist. I need to see him, fast.† She jumped up, steadied herself against a brief wave of giddiness, and walked past Chess, who was watching her in bewilderment. â€Å"No,† Paul said. â€Å"No, it's absolutely out of the question.† He waved his hands, then patted his pockets nervously, coming up empty. â€Å"Paul, please. I have to do this. And if you won't help me, I'll try it on my own. I think self-hypnosis should work. I've been doing a pretty good job of dreaming the past lately, anyway.† â€Å"It's†¦ too†¦ dangerous.† Paul said each word separately, then sank into his chair, hands at his temples. â€Å"Don't you remember what happened the last time?† Hannah felt sorry for him. But she said ruthlessly, â€Å"If I do it on my own, it may be even more dangerous. Right? At least if you hypnotize me you can be there to wake me up. You can throw a glass of water in my face again.† He looked up sharply. â€Å"Oh, yeah? And what if it doesn't work this time?† Hannah dropped her eyes. Then she raised them and looked at Paul directly. â€Å"I don't know,† she admitted quietly. â€Å"But I've still got to try. I have to know the truth. If I don't, I really think I may go insane.† She didn't say it melodramatically. It was a simple statement of fact. Paul groaned. Then he grabbed a pen and started chewing on it, glancing around the room. â€Å"What is it that you would want to know? Just presuming that I agreed to help you.† His voice sounded squashed. Hannah felt a surge of relief. â€Å"I want to know about this woman who keeps warning me,† she said. â€Å"Her name is Maya. And I want to know how I die in my other lives.† â€Å"Oh, terrific. That sounds like fun.† â€Å"I have to do it.† She took a deep breath. She wouldn't let herself look away from him, even though she could feel the warmth as her eyes filled. â€Å"Look, I know you don't understand. And I can't explain to you how important it is to me. But it is †¦ important.† There was a silence, then Paul said, â€Å"All right. All right. But only because I think it's safer for you to be with somebody.† Hannah whispered, â€Å"Thank you.† Then she blinked and unfolded a piece of paper. â€Å"I wrote down some questions for you to ask me.† â€Å"Great. Wonderful. I'm sure you'll be getting your degree in psychology soon.† But he took the paper. Hannah walked over to the couch and got herself settled. She shut her eyes, telling her muscles to relax. â€Å"Okay,† Paul said. His voice was very slightly unsteady, but Hannah could tell he was trying to make it soothing. â€Å"I want you to imagine a beautiful violet light†¦Ã¢â‚¬ 

Fresh Food and Canned Food Essay

Eating is most important activity in our life. Some people eat 2 times, 4 times, or some people in poor countries eat only 1 time a day. We live in a world where the variety of food is immense, and we are responsible for what we eat. We decide what we are about to eat and how it will affect our bodies. The three main differences between fresh food and canned food are flavor, health benefits, and cost. The most notable difference between these two kinds of foods is their flavor. Fresh food have great flavor and taste because they keep all their natural conditions. Canned food however, lack a lot of its flavor characteristics because there are some other chemical products added to the natural foods. Fresh food will have a greater taste and flavor when consumed just because of the time in which they have been prepared. Comparing both types of foods there is another difference. There is a health factor that affects both of them. Canned foods lose some of the original fresh food nutrients and vitamins when stored, and also it has to be tinned with many conservatives and chemical factors that prolong the shelf life and apparent freshness of the food but could also become toxic if consumed too often. Yet another difference between these two types of foods is the cost. Canned food are much more expensive than fresh foods. The benefit of buying tinned foods is that they are easier to find, for example, in a supermarket instead of the market like the fresh foods. When you look at the picture of the canned food it is so beautiful and it makes you buy it, but when you open it later you will see that they do not match and the taste is not good. Canned food requires less work than fresh food, even sometimes no work at all. If you decide to make food instead buying it ready you would have to spend at least 2 or 3 hours, but you will get delicious food that everyone will enjoy it. Fresh foods are always good for your health, but if you do not have enough time it is fine to get canned food. Eating canned food is not recommended, because it can make you sick and you might get diseases from that.

The Timeless Truths of Homer’s Iliad

James Hutchinson Ms. Spicer AP Literature 20 August 2010 Homer's Timeless Truths Is Homer's The Iliad relevant to today's society? Is this work a timeless parable depicting universal human truths transcending time and context or merely a superbly-crafted epic poem to be studied and admired for its stylistic brilliance? Has the text endured simply because of Homer's dramatic verse or because of the timeless human truths it conveys?Was it written to persuade readers to question the moral implications and savagery of war or simply to provide provocative entertainment? These questions have been posed for centuries yet rarely have been sufficiently answered. However, an astute student of contemporary politics, media, and entertainment cannot fail to notice that many Homeric themes, such as the celebration of war, the corruption of power, and man's desire for personal glory are as apparent in contemporary American life as they are within the pages of The Iliad.Though it is unknown whether or not the blind Greek poet intended to create a work that would have such an enduring impact on Western man, clearly the poem's underlying themes and the ominous questions it raises remain relevant in the twenty-first century. One of Homer's primary themes, the glorification of war and violence, is clearly relevant today. The celebration of war is omnipresent throughout The Iliad. To Homer's characters, battlefield courage, skill, and savagery are seen as both the ultimate means of serving one's country and of proving personal strength and integrity.War is depicted more as an opportunity to achieve a greater good and demonstrate individual valor than as a necessary evil to gain a larger political purpose. Homer's heroes focus more on the craft of battle itself than on the geopolitical goal they hope to obtain through the protracted bloody combat. In one scene, Hector responds to his army's reluctance to fight by proclaiming, â€Å"Fight for your country! That is the best, the only omen! You, why are you so afraid of war and slaughter? † (Homer 333) As a leader and a prince of Troy, Hector has been raised to embrace war as the only true chance for glory.For Hector, war brings honor to both his soldiers and the country for which they fight. Although he regrets the possibility of not living to see his son grow up, he believes that his purpose is to serve on the battlefield. Because of his integrity and willingness to die for Troy, Hector is the pride and joy of his family and of the Trojan army. His brother Paris, however, is widely scorned as a weakling and coward for his constant refusal to kill. At a time of war, pacifism is simply not an option.On high school campuses across the United States, we celebrate aggressive football stars and wrestlers far more than intellectual artists or peace activists. The parallels between Homer's depiction of a war-torn society and our own collapsing world are both unmistakeable and highly disturbing. There is, and alw ays has been, a human fascination with violence and sadism. Just as the ancient dramatist Homer depicts carnage with vivid detail and precision, contemporary Hollywood filmmakers such as Quentin Tarantino, Eli Roth, and Oliver Stone, while conveying the cost of war, also appeal to their audience's unquenchable blood lust.Despite their intentions or supposed â€Å"social commentary,† there is no denying that it is ultimately the gore that sells the tickets. The internet, television news programs, newspapers, and magazines garner far more advertising revenues depicting images of violence and destruction than anything with any sort of redeeming value. It is telling that two of the events from recent history that have sold the most books are the Holocaust and the Manson murders. In short: violence sells. The reprehensible slasher film â€Å"Saw† was a blockbuster.The family-oriented comedy â€Å"The Kids Are Alright† lagged in ticket sales. Without a doubt, we live in a culture in which violence is perceived not as a necessary evil for the greater good, but as a worthy and even heroic form of entertainment. Homer's Iliad also dramatizes the timeless truth that power corrupts. The arrogant, manipulative gods pulling strings from their plush thrones on Mount Olympus bring to mind modern-day politicians. They can be seen as archetypes of today's detached bureaucrats.Zeus and his fellow gods dispassionately toy with mortals, watching with amusement as they cut one another down on the blood-soaked battlefield of windy Troy. Shamelessly, like merciless puppeteers, they create tension between the mortals for their own personal entertainment, with little regard for the inevitable mayhem and carnage that ensues. Indeed, the ten-year conflict at Troy is indirectly sparked by the vain goddess Aphrodite's desire to be recognized as the â€Å"fairest† beauty among the goddesses, yet as soon as the fighting begins, she pleads neutrality.Similarly, Ze us himself shows little concern for the rampant slaughter among mortals taking place on his watch, even though initially he aids Achilles in his revenge against the Greeks. More than a few critics of the current wars in Iraq and Afghanistan have decried the dispassionate way in which U. S. â€Å"chickenhawk† non-combatants such as George Bush, Dick Cheney, and now Barack Obama have heartlessly made â€Å"strategic military decisions† from the safe environs of the White House that have had mortal consequences for U. S. troops on the front lines in Kabul and Baghdad.For many observers, the U. S. political elite bears more than slight resemblance to the gods of Mount Olympus. However, The Iliad shows not only how power corrupts on the broad, bureaucratic level but on the individual level as well. In fact, the poem's most self-serving and manipulative figure is without a doubt the mortal Agamemnon, who is only concerned about his own pleasure and personal gain. At the begi nning of the epic, he selfishly steals Achilles' war prize, the maiden Briseis, when he is forced to give up his own mistress.Outraged at this act of betrayal, Achilles exclaims that Agamemnon is â€Å"armored in shamelessness— always shrewd with greed! † (Homer 82) Although Agamemnon's actions seem unbelievably boorish and arrogant by today's standards, his behavior is not unlike that of any current leader who abuses his or her position of authority to achieve personal gain. On the local level, the city manager of Bell is now accused of looting his own very poor city's treasury of nearly one million dollars annually to purchase race horses and personal luxuries.Just as politicians and corporate CEOs pull strings and manipulate workers, so too schoolyard thugs and drug lords abuse the weak. The Iliad remains an unforgettable piece of literature not simply because it is beautifully-written, but also for its stark depiction of how the helpless are trampled by the strong. The third universal, timeless theme in The Iliad that is relevant today is how far men will go to attain personal glory. The main protagonist of the story, Achilles, seeks not merely wealth or vengeance against Troy, but also to be elevated to a god-like stature and leave behind an imperishable legacy.In this, he is not unlike any entrepreneur or world leader that hopes to â€Å"make a name for himself† by turning the tide of history, for better or for worse. Christian evangelist Billy Graham once declared, â€Å"The legacy we leave is not just in our possessions, but in the quality of our lives. † (Graham 48) For Achilles, his legacy will be the ferocity with which he wields his sword, and the body count of soldiers he cuts down. He rejects a simple, comfortable life at home for a vicious, unpredictable life of war, serene in the knowledge that this shall earn him eternal glory and lionization – as indeed it did.The longing for men to be remembered after their deaths is not a strictly Homeric theme. We live in a culture in which martyrdom is often perceived as the greatest virtue, resulting in the iconic status of figures ranging from Jesus Christ to Che Guevara. Men like these are often praised not simply for the quality of their lives, but also because of their willingness to fight and die for a cause. In America, joining the military and dying in combat is romanticized as the greatest possible act of heroism, whether or not the war itself has any moral worth.An early death is viewed as a noble death. Even when a young man dies from simple recklessness or self-hatred, as James Dean or Kurt Cobain, we still embrace them as tragic heroes; saints of their generation. In short: this is why Achilles fights. He cares far more about how his story will be told centuries after he is gone than for his own life in the present. Though he briefly becomes disillusioned with his life as a warrior after his conflict with Agamemnon, he regains his moti vation to fight and possibly die when he feels he must avenge Patroclus.He expresses the difficulty of his choice between an obscure life and an honorable death when he proclaims, â€Å"If I hold out here and lay siege to Troy, my journey home is gone, but my glory never dies. If I voyage back to the fatherland I love, my pride, my glory dies†¦ † (Homer 265) Eventually, though it is never mentioned in The Iliad, Achilles does meet his fate, without ever living to witness the climactic sack of Troy. However, his life is indeed remembered as one of near secular ainthood, and, just as he had hoped, his name is never erased from history. In the final analysis, was the Trojan War a worthwhile conflict in Homer's eyes? No. The cause was trivial; the cost in lives was enormous. However, once the war was under way, his heroes wrested honor and nobility from the battlefield. The reason for battle is practically irrelevant, but the ferocity with which the battles are fought is leg endary. The relevance of this to today's events is indisputable.For example,when the primary reason for the Iraq war was revealed to be largely if not wholly erroneous – the alleged presence of weapons of mass destruction – many argued that it had to be waged for the sake of American â€Å"honor,† a Homeric theme if ever there were one. Overall, The Iliad's enduring appeal rests in the universal human truths it presents. Namely, Homer tells us that man honors war more than peace, power corrupts us all, and we all thirst for immortal glory. That is why even in the twenty-first century, The Iliad remains a transcendent and gripping morality tale for the ages.