Space Debris Affirmative
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Brink: Collisions (2/3)(continued) by a paint fleck just 0.3 mm (0.01 of an inch) across that impacted at four kms (2.5 miles) per second. To cope with such threats, the ISS has some shielding but depends mainly on manoeuvering to get out of the way, an operation it has done several times. Satellites, too, can take evasive action using onboard thrusters, but this is costly because it reduces the craft's operational life. The ISS "is the most heavily shielded spacecraft ever flown," NASA says. "Critical components, e.g. habitable compartments and high pressure tanks, will normally be able to withstand the impact of debris as large as one centimetre (half an inch) in diameter." Space debris impacting missions now. Bergin 11 (Chris, editor of NASA spaceflight.com, NASA, Project ADR: Removal of large orbital debris interests NASA – Study, 1/9/11, http://www.nasaspaceflight.com/2011/01/project-adr-removal-large-orbital-debris-nasa-study/,rn) Small pieces of debris, such as MMOD (Micrometeoroid Orbital Debris) also impact the Station and the Space Shuttle orbiters, with small impacts regularly seen on the orbiter’s flight deck windows late in missions, whilst a few impacts have been found on the orbiter’s radiators once they return to their Orbiter Processing Facilities (OPF) for post flight processing. Endeavour after STS-118, and Atlantis after STS-115, provide such examples, with bullet-like holes was found on their radiators. Forensic examinations on Atlantis’ damage found a small piece of circuit board – originating from an “exploded Upper Stage” – in what was classed as the second largest orbital debris strike on an orbiter in the history of the program. Thankfully, the MMOD just missed one of Atlantis’ Freon-22 coolant loops, unlike Columbia’s STS-109, when a small piece of debris was lodged stuck in her coolant loop 2 and restricted the flow of Freon-22 in that loop. The amount of Freon-22 in the coolant loop was slightly below the flight rule red-limit, but after exhaustive analysis by the engineers on the ground, they decided to press on with the mission Threats of collisions and lack of satellite spots increase without the removal of space debris. Bergin 11 (Chris, editor of NASA spaceflight.com, NASA, Project ADR: Removal of large orbital debris interests NASA – Study, 1/9/11, http://www.nasaspaceflight.com/2011/01/project-adr-removal-large-orbital-debris-nasa-study/,rn) “Collision fragments replace other decaying debris through the next 50 years, keeping the total population approximately constant. Beyond 2055, the rate of decaying debris decreases, leading to a net increase in the overall satellite population due to collisions,” the presentation noted. “Major breakups may continue to occur (e.g., Fengyun-1C ASAT test, Briz-M explosion). Postmission disposal (such as the 25-year decay rule) will help, but will be insufficient to prevent the debris self-generating phenomenon from happening.” The threat of orbital debris – especially from a collision fragment standpoint – has been known for some time, such as via the 2005 “Assessment of the Current LEO Environment” study, which was cited in the ADR presentation. “A major study (using NASA’s LEGEND model) on the debris environment was conducted in 2005. The current debris population in the LEO region has reached the point where the environment is unstable and collisions will become the most dominant debris-generating mechanism in the future. “Only remediation of the near-Earth environment the removal of existing large objects from orbit can prevent future problems for research in and commercialization of space.” The mass of debris in orbit was also recently updated in October, 2010, which estimated that as much as 5,900 tons of debris exists, with 2,500 tons residing in Low Earth Orbit (LEO). Brink: Collisions (3/3)Space debris makes future satellite missions more risky and expensive. Marks 09 (Paul Marks, writer and Chief Technology Correspondent at New Scientist, New Scientist, Rocketing volumes of space debris are going to add significantly to the complexity of future space flights, 10/31/09, http://web.ebscohost.com/ehost/detail?sid=1c987d21-e57f-4d72-b30c-87bd1d4170f4%40sessionmgr15&vid=8&hid=18&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#db=a9h&AN=45391967, rn) A BURGEONING blizzard of space debris is going to have a major impact on the future economics of space flight. That was the prediction made this week by Hugh Lewis of the University of Southampton, UK, at the European Air and Space Conference in Manchester. His projections indicate that the number of close encounters between objects in orbit will rise 50 per cent in the next decade, and quadruple by 2059. Countermeasures will add greatly to the cost of future missions. Ever since the Soviet Union launched Sputnik 1 in 1957, satellite operators have used Earth orbit as a junkyard, dumping spent rocket stages and dead spacecraft there. As the danger of collisions with active spacecraft began to expose the cost of this folly, space agencies have tried not to add to the junk pile, but events have conspired against them. In 2007, the Chinese army used a missile to destroy a defunct weather satellite, and earlier this year an Iridium communications satellite collided with a derelict Russian vehicle. Both events added many thousands of debris shards to near-Earth space. The number of pieces of space debris has risen by 40 per cent in the past four years alone. The US air force Space Command now tracks 19,000 orbiting objects that are 10 centimetres or more across - including around 800 working satellites - and estimates that there are 500,000 smaller fragments in orbit. Lewis wondered what effect this growing debris field would have on managing future satellite operations. How much more often will mission controllers have to track debris and consider taking evasive action? To find out, he used data from an industry database called Socrates to correlate the change over time in the quantity of debris with the number of occasions on which objects come within 5 kilometres of each other. Then, using the predicted growth in the debris population over the next 50 years, he estimated the number of close approaches that are set to occur. Compared with the 13,000 close approaches per week now, his projection showed that there will be 20,000 a week in 2019 and upwards of 50,000 a week in 2059. From this he predicts that satellite operators will have to make five times as many collision avoidance manoeuvres in 2059 as they will in 2019. "There's going to be a big impact," says Lewis. "You're going to need more tracking to remove uncertainty about close approaches and undertake more manoeuvres.". Directory: files files -> Answer True False 2 points Question 2 files -> Integer programming and game theory files -> 4 Integer Programming files -> Bpa vehicle Window Repair Scenario #1 task: Procure vehicle window relacement. Objective files -> Pop Warner History files -> North Carolina Inclusion Initiative Mapping Where Children with ieps are Being Served Purpose files -> Fall 2013 Spring 2014 Program Data: Standard 1 Exhibit 4d files -> Hanban – asia society confucius classrooms network 2010 request for proposal files -> Northern England’s set-jetting locations Download 394.08 Kb. Share with your friends:
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